Startseite Naturwissenschaften Development of a validated spectrofluorimetric method for assay of sotalol hydrochloride in tablets and human plasma: application for stability-indicating studies
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Development of a validated spectrofluorimetric method for assay of sotalol hydrochloride in tablets and human plasma: application for stability-indicating studies

  • Fawzia A. Ibrahim , Amina M. El-Brashy , Mohamed I. El-Awady und Nora. A. Abdallah EMAIL logo
Veröffentlicht/Copyright: 23. Februar 2019
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Open Chemistry
Aus der Zeitschrift Open Chemistry Band 17 Heft 1

Abstract

The native fluorescence of sotalol hydrochloride (SOT) was used as a basis for establishing a new method of analysis for SOT in tablets and spiked human plasma. The fluorescence of SOT in water was measured at 310 nm when excited at 235 nm. The detection limit (LOD) was 0.37 ng/mL and the quantification limit (LOQ) was 1.08 ng/mL. The proposed method offers high sensitivity which permits determination of SOT, even if present in a very small amount, in human plasma. The obtained results were successfully compared to that of a reference pharmacopeial method and statistical analysis proved a good agreement between the results of both methods. Further investigation of the SOT stability upon exposure to various stress conditions, such as acidic, alkaline, oxidative and photolytic degradation conditions was also performed. The kinetics of acidic, alkaline and oxidative degradation of the drug showed a pseudo first order degradation reaction. A proposal of the degradation pathway was suggested and confirmed by developing a thin layer chromatographic method used for separation of SOT and its acidic and alkaline degradation products.

Graphical Abstract

Keywords: Sotalol HCl; Spectrofluorimetry; Stability-study; Tablets; Human plasma; Method validation

1 Introduction

Sotalol hydrochloride (SOT) is chemically designated as N-[4-[1-hydroxy-2-(propan-2-ylamino)ethyl]phenyl] methane-sulfonamide (Figure 1) [1] and is considered a non-cardio selective beta- blocker. Because of its proarrhythmic effects, it is usually used for severe or life-threatening arrhythmias [2].

Figure 1 Structural formula of SOT.
Figure 1

Structural formula of SOT.

The official method for the determination of SOT in the United States pharmacopeia [3] is based on HPLC while the official assay method in the British pharmacopeia [4] is based on non-aqueous titration with perchloric acid using potentiometric detection of the end point. A good guide to the work reported up to 1992 on the analysis of SOT is presented as a comprehensive monograph in the series of Analytical Profiles of Drug Substances [5]. Later, different analytical methods were developed for the determination of SOT alone or in combination with other drugs. A spectrofluorometric method for the determination of SOT based on fluorescence quenching technique was reported by Zhang et al. [6]. This method is based on quenching the fluorescence of the cucurbit[7]uril and palmatine complex by SOT with a linearity range of 0.10-3.60 μg/mL. Different spectrophotometric methods were reported for the determination of SOT based on the formation of charge transfer complex with 4-chloro-7-nitrobenzofurazan (NBD–Cl) reagent [7], derivative spectrophotometry [8, 9] and chemometric-assisted spectrophotometry [10]. The reported chromatographic methods for SOT determination include HPLC with UV detection [10, 11, 12, 13], fluorescence detection [14, 15, 16, 17, 18, 19, 20] and MS detection [21, 22, 23, 24]. Stability of SOT in oral suspension was studied during its storage at different temperatures using HPLC in order to investigate its shelf-life stability [25, 26]. Capillary electromigration techniques were also utilized for the determination of SOT [27, 28]. In addition, Ensafi et al. [29] and Heli et al. [30] reported two different electrochemical methods for the analysis of SOT.To the best of our knowledge, no stabilityindicating direct spectrofluorimetric method has been published for the determination of SOT.

The aim of the present study is to develop and validate a stability-indicating sensitive and simple spectrofluorimetric method for the determination of SOT under different stress conditions. The study is extended to the evaluation of SOT in pharmaceutical preparations and spiked human plasma.

2 Experimental

2.1 Apparatus

The spectrofluorimetric measurements were performed using Shimadzu spectrofluorophotometer (RF-1501) with a xenon lamp and excitation and emission slits set at 5 mm. Also, a 1-cm quartz cell was used. The photo stability study was carried out using a Camag UV-Lamp (S/N 29000), dual wavelength (254/336), 2 X 8W. The oxygen of the solvents was eliminated by sonication. For the analysis of spiked human plasma, a nylon membrane syringe filter (Wicom GmbH, Germany) was used with a pore size 0.45 μm. A Jenway pH-meter (model 3505) was used for pH measurements.

2.2 Materials and Methods

2.2.1 Chemicals and reagents

Sotalol hydrochloride was generously provided by AMOUN (Cairo, Egypt) with purity of 99.7% according to the official USP method [3] and was used as received in this study. Betacor® tablet containing 80 mg of SOT (a product of AMOUN) was purchased from a local pharmacy in Egypt. All the used solvents are of HPLC grade except for acetone and acetic acid that are of analytical reagent grade. Acetonitrile and n-propanol were products of Sigma-Aldrich, Germany while methanol was obtained from Tedia (USA). Tween 80, Hydroxy propyl β-cyclodextrin (HP-β-CD), acetone, ethanol, acetic acid (96%), sodium acetate trihydrate, boric acid, sodium hydroxide, hydrogen peroxide (30%) and sulfuric acid, were all obtained from El-Nasr Pharmaceutical Chemical Co. (Adwic, Egypt). Sodium dodecyl sulphate (SDS, 95%) was obtained from Winlab (UK). SDS, CD and Tween-80 were prepared as 0.5% w/v aqueous solutions. 0.2 M Acetate buffer was prepared for covering the pH range of (3.6–5.0) while 0.2 M borate buffer for the pH range of (7.5 – 9.5). Plasma samples were obtained from the Blood Bank of Mansoura University Hospital, Mansoura, Egypt. They were stored at -20˚C and were allowed to thaw gradually at room temperature. The analysis of spiked human plasma was performed after approval of the ethical committee of the Faculty of Pharmacy, Mansoura University on 11/6/2016. The double distilled water was obtained using A4000D Aquatron water still, Staffordshire, UK. The conductivity of random samples of the used water was measured and it ranged from 2.4 to 3.0 μs in most cases.

2.2.2 Preparation of Standard solutions

Stock solution of SOT (200.0 μg/mL) was prepared by dissolving 20 mg of the pure powder of the drug in 100 mL distilled water using volumetric flask. Several dilutions with distilled water were made to obtain a working standard solution. The stock solution was stable upon storage in the refrigerator for at least one month without alteration.

3 General Procedures

3.1 Construction of calibration graph

Aliquots from the standard solution covering the working concentration range (40-280 ng/mL) were transferred into a set of 10 mL volumetric flasks, then completed to the volume of the flask with distilled water. The prepared solution was then well mixed by sonication. The fluorescence intensities were measured at 310 nm when excited at 235 nm. The relative fluorescence intensities (RFI) obtained were plotted versus the corresponding concentrations of the drug and then the regression equation was derived.

3.2 Analysis of SOT in raw material

Accurate volumes of the working standard solution covering the linearity range of (40 - 280 ng/mL) were transferred into a set of 10 mL volumetric flasks. The emission intensity of prepared samples were measured and the content of SOT was reported as percentage in the raw material.

3.3 Analysis of SOT in tablets

Twenty tablets of the Betacor® 80 mg were weighed and grinded to fine powder. A precisely weighed amount of the mixed contents of the powdered tablets equivalent to 10 mg SOT was transferred into a 100 mL volumetric flask followed by the addition of about 70 mL of distilled water. The flask contents were then mixed by sonication for thirty minutes. The flask was then completed to the full volume with the distilled water. Filtration of the flask contents was performed to remove the insoluble additives. The filtrate was additionally diluted with distilled water to get the required working standard solution. Procedure mentioned in the “Construction of calibration graph” subheading was followed. The nominal contents were calculated through the corresponding regression equation.

3.4 Analysis of SOT in spiked human plasma

In 5.0 mL screw-capped tubes for centrifugation, 1 mL of human plasma was spiked with different volumes of SOT working standard solution and well mixed. Then, 3 mL of methanol was added as a precipitating agent [31] followed by the addition of distilled water to reach the full volume. After mixing by the vortex for 30 s, the screw capped tubes were centrifuged at 3,500 rpm for thirty minutes. The produced clear supernatants were then filtered with a membrane syringe filter (0.45 μm pore size) into a 20 mL beaker. Then, 1 mL of each filtrate was transferred to a 10 mL volumetric flask and completed with distilled water to obtain the final concentration covering linearity range of 40.0-200 ng/mL. The fluorescence intensities were measured at 340 nm when excited at 235 nm. A blank experiment was carried out simultaneously using double-distilled water in spiking the plasma instead of SOT.

3.5 Stability studies for SOT

3.5.1 Application of acidic and alkaline degradation

1 mL of SOT working standard solution (65 μg/mL) was transferred into a set of 25.0 mL volumetric flasks. To each flask, 5 mL of either 2 M NaOH or 2 M HCl were added separately. The solutions were kept at room temperature for different time intervals ranging from 0.0 to 60 minutes. The contents of each flask were neutralized to pH 7.0 with either 2 M HCl or 2 M NaOH. Degraded samples were diluted as appropriate with distilled water to obtain a measurable fluorescence signal within the concentration range of the calibration curve. Finally, the steps described in “procedure of calibration graph” subheading were performed to obtain concentration of SOT in the presence of its degradation products using the corresponding regression equation.

3.5.2 Application of oxidative degradation

1 mL of SOT working standard solution (65 μg/mL) was transferred into a set of 25 mL volumetric flasks, and to each flask, a 5 mL of 0.5% H2O2 solution was added. The solutions were kept at room temperature for different time intervals ranging from 0.0 to 60.0 minutes. At the specified time, degraded samples were diluted as appropriate with distilled water to obtain a measurable fluorescence signal within the concentration range of the calibration curve. Finally, the steps described in “Procedure for calibration graph” subheading were performed to obtain concentration of SOT in the presence of its degradation products. The drug concentration was then calculated as previously mentioned.

3.5.3 Application of photolytic degradation

1 mL of SOT working standard solution (65 μg/mL) was transferred into a set of 25.0 mL volumetric flasks and completed with distilled water to obtain 2.60 μg/mL. The prepared flasks were exposed to UV-lamp at its two wavelengths for different time intervals ranging from 0.5 to 3.0 hours. At a specified time, a 260 ng/mL solution was prepared from the exposed flasks. Under daylight, 1 mL of SOT working standard solution (65 μg/mL) was transferred into a set of 25.0 mL volumetric flasks and completed with distilled water to obtain 2.60 μg/mL. The prepared flasks were left in daylight for different times ranging from 0.5 to 8.0 hours. At a specified time, a 260 ng/mL solution was prepared from the exposed flasks. The drug concentration was then calculated as previously mentioned.

Ethical approval: The conducted research is not related to either human or animal use.

4 Results and discussion

Based on the previously reported HPLC-fluorescence method [15], the fluorescence intensity was examined at 310 nm after excitation at 235 nm. As a consequence, the present work aims at discovering a new technique for the analysis of SOT in tablets and human plasma in addition to studying the stability of SOT under various stress conditions, according to the ICH guidelines. SOT has a strong native fluorescence at 235/310 nm (Figure 2). Various experimental parameters affecting the fluorescence intensities of SOT were carefully studied and optimized.

Figure 2 Fluorescence spectra of 200.0 ng/mL of SOT in water. (A, A”): Excitation and emission spectra of SOT, (B, B”): Excitation and emission spectra of water.
Figure 2

Fluorescence spectra of 200.0 ng/mL of SOT in water. (A, A”): Excitation and emission spectra of SOT, (B, B”): Excitation and emission spectra of water.

4.1 Selection of optimum experimental conditions

4.1.1 pH effect

Various kinds of buffers covering the whole pH range were utilized to investigate the pH effect on the fluorescence intensity of SOT. Among the buffers utilized are 0.2 M acetate buffer which covers the pH range from 3.6 to 5 and 0.2 M borate buffer which covers the pH range from 7.5 to 9.5. For the studied drug, no buffer was used throughout the study, since water alone resulted in the highest fluorescence intensity, as shown in Figure 3.

Figure 3 Effect of pH (0.2 M acetate buffer, 0.2 M Borate buffer, 0.1 M H2SO4, 0.1 M NaOH and 0.1 M HCl) on the RFI of SOT (180.0 ng/mL) and n=5.
Figure 3

Effect of pH (0.2 M acetate buffer, 0.2 M Borate buffer, 0.1 M H2SO4, 0.1 M NaOH and 0.1 M HCl) on the RFI of SOT (180.0 ng/mL) and n=5.

4.1.2 Diluting solvent effect

Various diluting solvents were investigated to show their influence on the RFI of SOT. The solvents included in this investigation were water, methanol, ethanol, n-propanol, iso-propanol, acetonitrile, and acetone. Also, the effects of 0.1 M HCl, 0.1 M H2SO4 and 0.1 M NaOH were studied. Methanol usage resulted in a decrease in the RFI of SOT, while ethanol, n-propanol, acetonitrile and iso-propanol resulted in a very high blank reading. On the other hand, the fluorescence of SOT was greatly quenched by dilution with acetone. Also, all 0.1 M HCl, 0.1 M H2SO4 and 0.1 M NaOH resulted in a decrease in the RFI of SOT. So, the distilled water was the optimum solvent, as it had the lowest blank reading, and consequently the highest RFI with reproducible results, as shown in Figure 4.

Figure 4 Effect of diluting solvents on the RFI of SOT (180.0 ng/mL) and n=5.
Figure 4

Effect of diluting solvents on the RFI of SOT (180.0 ng/mL) and n=5.

4.1.3 Surfactant effect

Various types of surfactants, including anionic, nonionic and macromolecule surfactants, such as sodium dodecyl sulphate (SDS), tween 80 and b-cyclodextrin were used to investigate the effect of surfactant on RFI of SOT. All these surfactant did not have any positive effect on the fluorescence intensity of SOT. So, the study was completed without surfactant, as shown in Figure 5.

Figure 5 Effect of surfactants on the RFI of SOT (180.0 ng/mL) and n=5.
Figure 5

Effect of surfactants on the RFI of SOT (180.0 ng/mL) and n=5.

4.1.4 Time

Time factor effect was investigated and the results showed that the fluorescence intensity stayed unchanged for at least 4 hours.

4.2 Method validation

4.2.1 Linearity and range

Calibration curve was constructed in the range of 40 to 280 ng/mL. The relative fluorescence intensity for each concentration was recorded in triplicates then plotted against the corresponding concentration to obtain the calibration graph.

Statistical analysis [32] of the data is summarized in Table 1. The data presented in the table verified the linearity of the calibration graph as homoscedasticity test shows F test value = 2.75 and the tabulated F value = 3.18 at significance level of 95% and degrees of freedom of 9 for both numerator and denominator which ensures the homoscedasticity of the variance and the validity of the proposed method in the studied range. Compared to the previously reported quenching spectrofluorometric method [6], the developed method offers much higher sensitivity with fewer steps and lower cost.

Table 1

Analytical performance data for the determination of SOT by the proposed method.

ParameterValue
Linearity range (ng/mL)40 – 280
Intercept (a)95.148
Slope (b)3.113
Correlation coefficient (r)0.9998
S.D. of residuals (Sy/x)2.163
S.D. of intercept (Sa)0.337
S.D. of slope (Sb)0.009
S.D.1.042
% RSD[a]1.044
% Error[b]0.330
LOD[c] (ng/mL)0.358
LOQ[d] (ng/mL)1.084
Homoscedacticity[e]Calculated F2.75
Tabluted F3.18

4.2.2 Detection and quantification limit

Detection limit (LOD) and quantification limit (LOQ) were calculated according to the ICH Q2 (R1) recommendation [33] and were found to be 0.37 and 1.08 ng/mL, respectively. They were calculated from the standard deviation of the response and the slope of the calibration curve in accordance to the following equations:

LOQ =10 Sa/b                LOD =3.3Sa/b

where, Sa is standard deviation of the intercept of the calibration curve and, b is the slope of the calibration curve. The results are shown in Table 1.

4.2.3 Accuracy and precision

Statistical analysis (using Student’s t -test and variance ratio F -test at p=0.05 and degrees of freedom for t- test 11 and for F- test 9 for numerator and 2 for denominator, respectively [32]) of the results obtained by the designed method compared to the official USP reference one [3] revealed no differences between them regarding accuracy and precision, as presented in Table 2.

Table 2

Assay results for the determination of SOT in pure form by the proposed method and the reference USP method.

CompoundProposed methodReference USP method [3]
SOTAmount taken (ng/mL)Amount found (ng/mL)% FoundAmount taken (μg/mL)Amount found (μg/mL)% Found
4039.88299.71100100.007100.01
6060.262100.44150149.98899.99
10098.53498.53200200.00599.20
160161.858101.16
180178.41499.12
200201.400100.70
220220.801100.36
240241.829100.76
260258.31999.35
280278.80899.57
Mean99.7999.70
± S.D.1.040.49
t-test0.46 (2.2)[*]
F-test3.3 (19.3)[*]

  1. N.B. Each result was the average of three separate determinations.

Precision was calculated in terms of intra-day repeatability and inter-day reproducibility. The intra-day repeatability was evaluated in terms of %RSD by the analysis of three different concentrations of the pure drug for each in triplicates on a single day. The inter-day reproducibility was checked on 3 different days by repeating the analysis of the same concentrations levels as for intra-day repeatability. The intra-day repeatability and inter-day reproducibility results are summarized in Table 3.

Table 3

Precision data for the determination of SOT by the proposed method.

ParameterSOT (ng/mL)
80160240
Intra-day% Found99.0999.25100.09
100.60100.40101.40
100.9099.3799.69
Mean100.1999.67100.39
S.D.0.970.630.89
% RSD0.960.630.89
% Error[*]0.550.360.51
Inter-day% Found100.1599.3599.69
98.57100.61100.09
101.90102.24100.89
Mean100.21100.73100.22
S.D.1.661.440.61
% RSD1.661.430.61
% Error[*]0.960.830.35

  1. N. B. Each result was the average of three separate determinations.

4.2.4 Specificity

It was indicated that the excipients of the tablet preparation as microcrystalline cellulose, magnesium stearate and lactose did not affect the results of the designed method as shown in Table 4.

Table 4

Assay results for the determination of SOT in its tablet dosage form by the proposed method and the reference USP method.

ParameterProposed methodReference USP method [3]
Amount taken (ng/mL)Amount found (ng/mL)% FoundAmount taken (μg/mL)Amount found (μg/mL)% Found
Betacor tablets8079.56899.46100100.083100.08
(80 mg)160160.960100.60150149.84899.90
240239.49699.79200200.073100.44
Mean99.95100.14
± S.D.0.5870.274
t-test0.51(2.78)[*]
F-test4.55 (19)[*]

  1. N.B. Each result was the average of three separate determinations.

5 Application

5.1 Assay of pharmaceutical products

One of the purposes of the current study was to determine SOT in tablet dosage form. Results were compared to the results obtained from the reference method using Student’s t-test and F-test at p=0.05 and degrees of freedom for t-test 4 and for F-test 2 for numerator and 2 for denominator, respectively. Table 4 shows that there was no significant difference between the results of the designed method and the official one.

5.2 Application of the designed method to the determination of the SOT in spiked human plasma

The maximum plasma concentration of SOT was 1.1–1.4 mg/ L after daily oral doses of 400 mg for 5 days. SOT was

absorbed completely from the gastrointestinal tract (GIT) after oral administration with bioavailability of about 90% [1].

The analysis of SOT in spiked human plasma was performed through a simple extraction procedure [31]. According to the above described experimental conditions, a linear relationship was established by plotting the RFI against the drug concentration in ng/mL. Assay results for the determination of SOT in spiked human plasma samples using proposed method is shown in Table 5.

Table 5

Assay results for the determination of SOT in spiked human plasma samples using the proposed method.

ParameterConcentration taken, (ng/mL)Concentration found (ng/mL)% Found
SOT4040.361100.90
100101.203101.20
160158.26298.91
180177.6998.72
200202.853101.43
S.D.1.25
% RSD [a]1.24
S% Error [b]0.57
Mean % Found100.34

The proposed method shows satisfactory results for the determination SOT in spiked human plasma over a concentration range of 40 to 200 ng/mL. Figure 6 shows fluorescence spectra for blank and spiked human plasma sample.

Figure 6 Emission spectra of SOT in spiked human plasma where (a) plasma blank and (b, c, d, e, f and g) SOT in spiked human plasma in a concentration of 40, 100, 120, 160, 180 and 200 ng/mL.
Figure 6

Emission spectra of SOT in spiked human plasma where (a) plasma blank and (b, c, d, e, f and g) SOT in spiked human plasma in a concentration of 40, 100, 120, 160, 180 and 200 ng/mL.

5.3 Application of stability studies and degradation kinetics

5.3.1 Degradation in acidic and alkaline medium

As a sulfonamide, SOT was found to be easily degraded by acidic and alkaline hydrolysis. The degradation in 0.2 M-2.0 M HCl or NaOH at room temperature and at 100°C was studied. At room temperature, the degradation was very slow in 0.2 M-1.0 M HCl and NaOH. However, about 30% of the drug degraded in 2 M HCl and NaOH after thirty minutes, as revealed by the decrease in RFI of the SOT. So, 2 M HCl or NaOH was found to be the suitable concentration to be used for degradation studies. The degradation of SOT in acidic and alkaline medium at room temperature was found to be time dependent, as it was noticed that RFI of SOT decreased as time intervals increased in 2 M HCl or NaOH (Figure 7).

Figure 7 Effect of different exposure time with: (A) 2 M NaOH and (B) 2 M HCl on the RFI of SOT (260.0 ng/mL) at room temperature (n=5).
Figure 7

Effect of different exposure time with: (A) 2 M NaOH and (B) 2 M HCl on the RFI of SOT (260.0 ng/mL) at room temperature (n=5).

Plotting the logarithm of concentrations of SOT against time produced straight lines which indicates pseudo first order reaction (Figure 8A and B ). The apparent pseudo first order rate constants and half-life times for both alkaline and acidic degradation were calculated (Table 6). The acidic and basic treatments of SOT were expected to cause cleavage of its sulfonamide bond [11]. The Proposal of the degradation pathways of SOT were demonstrated in Scheme1.

Table 6

Results of the degradation study of SOT (260ng/mL) under different stress conditions on the kinetic parameters of SOT at room temperature

Degradation conditionReaction rateHalf life time
constant(t, min) 1/2
(K, min−1)
Alkaline degradation (2 M NaOH at room temp.)0.01217856.9
Acidic degradation (2 M HCl at room temp.)0.00711697.4
Oxidative degradation (0.5% H2O2 at room temp.)0.01008168.7

Thin layer chromatography (TLC) of SOT and its degradation products (after its acidic and alkaline degradation) was developed using aluminum cards of silica gel and a developing TLC eluent system consisting of methanol:chloroform:25% ammonium hydroxide (6:4:0.05). Visualization of the separated spots was carried out under UV lamp at 254 nm. Rf of the acidic and alkaline degradation product was 0.85 while for intact drug was 0.62. The proposal of the degradation pathway is indicated in Scheme 1.

Scheme 1 The proposed pathway of alkaline, acidic and oxidative degradation of SOT.
Scheme 1

The proposed pathway of alkaline, acidic and oxidative degradation of SOT.

5.3.2 Oxidative degradation

Obvious degradation of SOT was observed with oxidative conditions, as treating the drug with high concentrations of H2O2 (30%) solution at room temperature resulted in immediate degradation of SOT, while treating it with lower concentrations of H2O2 resulted in very slow degradation.

As shown in Figure 9, the RFI of SOT decreased with increasing exposing time to 0.5% H2O2. Plotting the logarithm of concentrations of SOT against time produced straight lines which indicate pseudo first order reaction for the oxidative degradation of SOT (Figure 8C). Moreover, the first order rate constants and half-life times for oxidative degradation were calculated (Table 6).

Figure 8 Semilogarithmic plot of SOT (260.0 ng/mL) versus different exposure times with: (A) 2 M NaOH, (B) 2 M HCl and (C) 0.5% H2O2 at room temperature (n=5).
Figure 8

Semilogarithmic plot of SOT (260.0 ng/mL) versus different exposure times with: (A) 2 M NaOH, (B) 2 M HCl and (C) 0.5% H2O2 at room temperature (n=5).

Figure 9 Effect of different exposure time with 0.5% H2O2 on the RFI of SOT (260.0 ng/mL) at room temperature (n=5).
Figure 9

Effect of different exposure time with 0.5% H2O2 on the RFI of SOT (260.0 ng/mL) at room temperature (n=5).

Upon using 0.5% H2O2 solution, about 30% degradation of SOT was observed after 30 minutes, as revealed by the decrease in the RFI of SOT. The pathway of the oxidative degradation of SOT was assumed to proceed by oxidation of hydroxyl group into carbonyl group as illustrated in Scheme 1. This assumption can be confirmed by the work published by Abdelmonem et al. [11], De Souza et al. [34] and Liu and Wang [35]. This proposal can explain the observed decrease in the RFI of SOT upon oxidative degradation due to the electron withdrawing effect of the formed carbonyl group.

5.3.3 Photolytic degradation

The stability of SOT under the effect of UV-light was studied by exposing the SOT to the UV-light. No degradation of SOT upon exposure to the UV-light at 366 nm was observed, even after 48 hr. On the other hand, by exposing SOT solutions to UV-light at 254 nm, very limited degradation of SOT was observed (about 10%) after 24 h of exposure.

6 Conclusion

This study reported a green, sensitive, rapid and time-saving spectrofluorimetric method for the determination of SOT. The suggested method could be used for the determination of SOT in pharmaceutical preparations and biological fluids. Besides, the importance of the suggested method is extended to be used as a stability-indicating assay method. It does not need the complicated handling related to chromatographic techniques. Furthermore, the developed method offers better sensitivity and less experimental steps than the previously reported quenching spectrofluorimetric method. Also, there is no need for organic solvent usage, which makes the method of lower toxicity and cost. On the basis of its high sensitivity, greenness and simplicity, the designed method could be convenient for routine quality control in the pharmaceutical industry.

  1. Conflict of interest Authors declare no conflict of interest.

References

[1] Moffat A.C., Osselton M.D., Widdop B., Clarke’s Analysis of Drugs and Poisons in Pharmaceuticals, Body Fluids and Postmortem Material, fourth ed., Pharmaceutical Press, London, 2011.Suche in Google Scholar

[2] Brayfield A.E, Martindale: The Complete Drug Reference, Online version (2017), Pharmaceutical Press, London. (http://www.medicinescomplete.com) [Accessed 01.10.2017].Suche in Google Scholar

[3] The United States Pharmacopeia (USP 40), The National Formulary (NF 35), Online version, US Pharmacopeial Convention, Rockville, 2017, (http://www.uspnf.com) [Accessed 01.10.2017].Suche in Google Scholar

[4] The British Pharmacopoeia, Electronic version [CD-ROM], The Stationery Office, London, 2013.Suche in Google Scholar

[5] Foster R. T., Carr R. A., Sotalol, In: Brittain H.G. (Ed.), Analytical Profiles of Drug Substances and Excipients, Volume 21, Academic Press, San Diego, 1992.10.1016/S0099-5428(08)60400-1Suche in Google Scholar

[6] Zhang H.-M., Yang J.-Y., Du L.-M., Li C.-F., Wu H., Determination of sotalol by fluorescence quenching method., Anal. Methods, 2011, 3(5), 1156-1162.10.1039/c0ay00728eSuche in Google Scholar

[7] Amin A.S., Ragab G.H., Saleh H., Colorimetric determination of β-blockers in pharmaceutical formulations, J Pharm Biomed Anal, 2002, 30(4), 1347-1353.10.1016/S0731-7085(02)00205-4Suche in Google Scholar

[8] Santoro M.I.R.M., Tsubone C., Gomes F.P., Kedor-Hackmann E.R.M., García P.L., Development and Validation of High Performance Liquid Chromatographic and UV-Derivative Spectrophotometric Methods for the Determination of Sotalol Hydrochloride in Tablets, Anal.l Lett., 2008, 41(11), 2044-2057.10.1080/00032710802209342Suche in Google Scholar

[9] Stolarczyk M., Apola A., Malanka A., Kwiecien A., Wrona E., Opoka W., Determination of Sotalol, Oxprenolol and Labetalol in Binary Mixtures and in Spiked Human Serum by Derivative Spectrophotometric Method, Acta Pol Pharm, 2017, 74(1), 93-102.Suche in Google Scholar

[10] Abdel Hameed E.A., Abdel Salam R.A., Hadad G.M., Chemometric-assisted spectrophotometric methods and high performance liquid chromatography for simultaneous determination of seven beta-blockers in their pharmaceutical products: a comparative study. Spectrochimica ActaAMol. Biomol. Spectrosc., 2015, 141, 278-86.10.1016/j.saa.2015.01.035Suche in Google Scholar

[11] Abdelmonem A.A., Ragab H.G., Hashem H., Bahgat E., A fast stability-indicating HPLC method for determination of sotalol hydrochloride in bulk powder and in dosage form, Main Group Chemistry, 2016, 15, 209–219.10.3233/MGC-150200Suche in Google Scholar

[12] Wang W., Zhao G., Jiang W., Zuo A., Bi H., Determination of sotalol hydrochloride by reversed-phase high performance liquid chromatography, Chinese journal of chromatography/ Zhongguo hua xue hui, 2000, 18(2), 178-180.Suche in Google Scholar

[13] Hooper W.D., Baker P.V., Enantioselective analysis of sotalol in plasma by reversed-phase high-performance liquid chromatography using diastereomeric derivatives, J. Chromatogr. B Biomed. Sci. Appl., 1995, 672(1), 89-96.10.1016/0378-4347(95)00196-PSuche in Google Scholar

[14] da Cunha L.C., Gondim F.A., de Paola A.A., Barros I.C., Santos S.R., An improved HPLC-fluorescence stereoselective method for analysis of (+)-S- and (-)-R-sotalol enantiomers in plasma sample, Boll. Chim. Farm., 2001, 140(6), 448-454.Suche in Google Scholar

[15] SantosS.R.PapiniO.OmosakoC.E.PereiraM.D.QuintavalleT.B.G.RiccioM.F.KurataA.PereiraV.A.Di-PietroG.Della-PaschoaO.E.DanhofM.Da-LuzP.L.A simple HPLC-fluorescence method for the measurement of R,S-sotalol in the plasma of patients with life-threatening cardiac arrhythmiasBraz. J. Med. Biol. Res20003319920410.1590/S0100-879X2000000200006Suche in Google Scholar

[16] Zarghi A., Foroutan S.M., Shafaati A., Khoddam A., Development an ion-pair liquid chromatographic method for determination of sotalol in plasma using a monolithic column, J. Pharm. Biomed. Anal., 2006, 41(4), 1433-1437.10.1016/j.jpba.2006.03.007Suche in Google Scholar

[17] Rbeida O., Christiaens B., Chiap P., Hubert P., Lubda D., Boos K.S., Crommen J., Fully automated LC method for the determination of sotalol in human plasma using restricted access material with cation exchange properties for sample clean-up, J. Pharm. Biomed. Anal., 2003, 32(4-5), 829-38.10.1016/S0731-7085(03)00186-9Suche in Google Scholar

[18] Läer S., Wauer I., Scholz H., Small blood volumes from children for quantitative sotalol determination using high-performance liquid chromatography, J. Chromatogr. B Biomed. Sci. Appl., 2001, 753(2), 421-425.10.1016/S0378-4347(00)00562-4Suche in Google Scholar

[19] Fiset C., Philippon F., Gilbert M., Turgeon J., Stereoselective high-performance liquid chromatographic assay for the determination of sotalol enantiomers in biological fluids, J. Chromatogr. B Biomed. Sci. Appl., 1993, 612(2), 231-237.10.1016/0378-4347(93)80168-4Suche in Google Scholar

[20] Baranowska I., Wilczek A., Simultaneous RP-HPLC determination of sotalol, metoprolol, [small alpha]-hydroxymetoprolol, paracetamol and its glucuronide and sulfate metabolites in human urine, Anal. Sci., 2010, 25(6), 769-772.10.2116/analsci.25.769Suche in Google Scholar PubMed

[21] Badaloni E., D’Acquarica I., Gasparrini F., Lalli S., Misiti D., Pazzucconi F., Sirtori C. R., Enantioselective liquid chromatographic-electrospray mass spectrometric assay of β-adrenergic blockers: application to a pharmacokinetic study of sotalol in human plasma, J. Chromatogr.B, 2003, 796(1), 45-54.10.1016/j.jchromb.2003.07.001Suche in Google Scholar PubMed

[22] Feng Z., Yu S., Liu W., Yang L., Liu Y., Zhai S., Wang F., Zhang X., A simple and sensitive LC-MS/MS method for the determination of sotalol in rat plasma, Biomed. Chromatogr., 2015, 29(8), 1167-1172.10.1002/bmc.3403Suche in Google Scholar PubMed

[23] Tomková J., Ondra P., Kocianová E., Václavík J., Fast and sensitive analysis of beta blockers by ultra-high-performance liquid chromatography coupled with ultra-high-resolution TOF mass spectrometry, Biomed.Chromatogr., 2017, 31(7), 1-7.10.1002/bmc.3911Suche in Google Scholar PubMed

[24] Li S., Liu G.,; Jia J., Liu Y., Pan C., Yu C., Cai Y., Ren J., Simultaneous determination of ten antiarrhythic drugs and a metabolite in human plasma by liquid chromatography— tandem mass spectrometry. J. Chromatogr. B, 2007, 847(2), 174-181.10.1016/j.jchromb.2006.10.013Suche in Google Scholar PubMed

[25] Sidhom M.B., Rivera N., Almoazen H., Taft D.R., Kirschenbaum H.L., Stability of sotalol hydrochloride in extemporaneously prepared oral suspension formulations, Int. J. Pharm. Compd., 2005, 9(5), 402-6.Suche in Google Scholar

[26] Nahata M.C., Morosco R.S., Stability of sotalol in two liquid formulations at two temperatures, Ann. Pharmacother., 2003, 37(4), 506-9.10.1345/aph.1C333Suche in Google Scholar PubMed

[27] Dogrukol-Ak D., Dal A.G., Tunçel M., Determination of Sotalol in Tablets and Serum by CZE, Chromatographia, 2007, 66(1), 159-163.10.1365/s10337-007-0312-9Suche in Google Scholar

[28] Zi-Wang S., Tong P., Zheng L., Zhang L., Separation and Determination of beta-Blockers Doping in Urine by Capillary Electrophoresis Amperometric Detection, Chinese J. Anal. Chem., 2008, 36(12), 1624-1628.Suche in Google Scholar

[29] Ensafi A.A., Allafchian A.R., Rezaei B., Mohammadzadeh R., Characterization of carbon nanotubes decorated with NiFe2O4 magnetic nanoparticles as a novel electrochemical sensor: Application for highly selective determination of sotalol using voltammetry, Mater. Sci. Eng. C, 2013, 33(1), 202-208.10.1016/j.msec.2012.08.031Suche in Google Scholar PubMed

[30] Heli H., Jabbari A., Zarghan M., Moosavi-Movahedi A.A., Copper nanoparticles–carbon microparticles nanocomposite for electrooxidation and sensitive detection of sotalol, Sens. Actuator. B-Chem., 2009, 140(1), 245-251.10.1016/j.snb.2009.04.021Suche in Google Scholar

[31] Khalil A., El-Sayed K., Belal F., Khalil N.Y., Hamann M., Spectrofluorimetric determination of manzamine A in spiked human urine and plasma, Die Pharmazie, 2003, 58(6), 385-8.Suche in Google Scholar

[32] Miller J.N. and Miller J.C., Statistics and chemometrics for analytical chemistry, fifth ed., Pearson Education Limited, Harlow, England, 2005.Suche in Google Scholar

[33] ICH Harmonised Tripartite Guidelines, Validation of analytical procedures: text and methodology Q2(R1), 2016. ( http://www.ich.org/products/guidelines/quality/article/quality-guidelines.html) [Accessed 01.10.2017].Suche in Google Scholar

[34] De Souza A., Baylocq D., Pellerin F., Degradation oxydative des sulfamides a usage therapeutique Isolement structure et methodes d’analyse des produits formes, Talanta, 1988, 35(11), 875-878.10.1016/0039-9140(88)80205-4Suche in Google Scholar

[35] Liu Y., Wang J., Degradation of sulfamethazine by gamma irradiation in the presence of hydrogen peroxide, J.Hazard. Mater., 2013, 250-251, 99-105.10.1016/j.jhazmat.2013.01.050Suche in Google Scholar PubMed

Received: 2018-04-29
Accepted: 2018-10-31
Published Online: 2019-02-23

© 2019 Fawzia A. Ibrahim et al., published by De Gruyter

This work is licensed under the Creative Commons Attribution 4.0 Public License.

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https://doi.org/10.1515/chem-2019-0008
Schlagwörter für diesen Artikel
Sotalol HCl; Spectrofluorimetry; Stability-study; Tablets; Human plasma; Method validation
Creative Commons
BY 4.0

Artikel in diesem Heft

  1. Regular Articles
  2. Research on correlation of compositions with oestrogenic activity of Cistanche based on LC/Q-TOF-MS/MS technology
  3. Efficacy of Pyrus elaeagnifolia subsp. elaeagnifolia in acetic acid–induced colitis model
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  41. Preparation and spectroscopic studies of Fe(II), Ru(II), Pd(II) and Zn(II) complexes of Schiff base containing terephthalaldehyde and their transfer hydrogenation and Suzuki-Miyaura coupling reaction
  42. Complex formation in a liquid-liquid extraction-chromogenic system for vanadium(IV)
  43. Synthesis, characterization (IR, 1H, 13C & 31P NMR), fungicidal, herbicidal and molecular docking evaluation of steroid phosphorus compounds
  44. Analysis and Biological Evaluation of Arisaema Amuremse Maxim Essential Oil
  45. A preliminary assessment of potential ecological risk and soil contamination by heavy metals around a cement factory, western Saudi Arabia
  46. Anti- inflammatory effect of Prunus tomentosa Thunb total flavones in LPS-induced RAW264.7 cells
  47. Collaborative Influence of Elevated CO2 Concentration and High Temperature on Potato Biomass Accumulation and Characteristics
  48. Methods of extraction, physicochemical properties of alginates and their applications in biomedical field – a review
  49. Characteristics of liposomes derived from egg yolk
  50. Preparation of ternary ZnO/Ag/cellulose and its enhanced photocatalytic degradation property on phenol and benzene in VOCs
  51. Influence of Human Serum Albumin Glycation on the Binding Affinities for Natural Flavonoids
  52. Synthesis and antioxidant activity of 2-methylthio-pyrido[3,2-e][1,2,4] triazolo[1,5-a]pyrimidines
  53. Comparative study on the antioxidant activities of ten common flower teas from China
  54. Molecular Properties of Symmetrical Networks Using Topological Polynomials
  55. Synthesis of Co3O4 Nano Aggregates by Co-precipitation Method and its Catalytic and Fuel Additive Applications
  56. Phytochemical analysis, Antioxidant and Antiprotoscolices potential of ethanol extracts of selected plants species against Echinococcus granulosus: In-vitro study
  57. Silver nanoparticles enhanced fluorescence for sensitive determination of fluoroquinolones in water solutions
  58. Simultaneous Quantification of the New Psychoactive Substances 3-FMC, 3-FPM, 4-CEC, and 4-BMC in Human Blood using GC-MS
  59. Biodiesel Production by Lipids From Indonesian strain of Microalgae Chlorella vulgaris
  60. Miscibility studies of polystyrene/polyvinyl chloride blend in presence of organoclay
  61. Antibacterial Activities of Transition Metal complexes of Mesocyclic Amidine 1,4-diazacycloheptane (DACH)
  62. Novel 1,8-Naphthyridine Derivatives: Design, Synthesis and in vitro screening of their cytotoxic activity against MCF7 cell line
  63. Investigation of Stress Corrosion Cracking Behaviour of Mg-Al-Zn Alloys in Different pH Environments by SSRT Method
  64. Various Combinations of Flame Retardants for Poly (vinyl chloride)
  65. Phenolic compounds and biological activities of rye (Secale cereale L.) grains
  66. Oxidative degradation of gentamicin present in water by an electro-Fenton process and biodegradability improvement
  67. Optimizing Suitable Conditions for the Removal of Ammonium Nitrogen by a Microbe Isolated from Chicken Manure
  68. Anti-inflammatory, antipyretic, analgesic, and antioxidant activities of Haloxylon salicornicum aqueous fraction
  69. The anti-corrosion behaviour of Satureja montana L. extract on iron in NaCl solution
  70. Interleukin-4, hemopexin, and lipoprotein-associated phospholipase A2 are significantly increased in patients with unstable carotid plaque
  71. A comparative study of the crystal structures of 2-(4-(2-(4-(3-chlorophenyl)pipera -zinyl)ethyl) benzyl)isoindoline-1,3-dione by synchrotron radiation X-ray powder diffraction and single-crystal X-ray diffraction
  72. Conceptual DFT as a Novel Chemoinformatics Tool for Studying the Chemical Reactivity Properties of the Amatoxin Family of Fungal Peptides
  73. Occurrence of Aflatoxin M1 in Milk-based Mithae samples from Pakistan
  74. Kinetics of Iron Removal From Ti-Extraction Blast Furnace Slag by Chlorination Calcination
  75. Increasing the activity of DNAzyme based on the telomeric sequence: 2’-OMe-RNA and LNA modifications
  76. Exploring the optoelectronic properties of a chromene-appended pyrimidone derivative for photovoltaic applications
  77. Effect of He Qi San on DNA Methylation in Type 2 Diabetes Mellitus Patients with Phlegm-blood Stasis Syndrome
  78. Cyclodextrin potentiometric sensors based on selective recognition sites for procainamide: Comparative and theoretical study
  79. Greener synthesis of dimethyl carbonate from carbon dioxide and methanol using a tunable ionic liquid catalyst
  80. Nonisothermal Cold Crystallization Kinetics of Poly(lactic acid)/Bacterial Poly(hydroxyoctanoate) (PHO)/Talc
  81. Enhanced adsorption of sulfonamide antibiotics in water by modified biochar derived from bagasse
  82. Study on the Mechanism of Shugan Xiaozhi Fang on Cells with Non-alcoholic Fatty Liver Disease
  83. Comparative Effects of Salt and Alkali Stress on Antioxidant System in Cotton (Gossypium Hirsutum L.) Leaves
  84. Optimization of chromatographic systems for analysis of selected psychotropic drugs and their metabolites in serum and saliva by HPLC in order to monitor therapeutic drugs
  85. Electrocatalytic Properties of Ni-Doped BaFe12O19 for Oxygen Evolution in Alkaline Solution
  86. Study on the removal of high contents of ammonium from piggery wastewater by clinoptilolite and the corresponding mechanisms
  87. Phytochemistry and toxicological assessment of Bryonia dioica roots used in north-African alternative medicine
  88. The essential oil composition of selected Hemerocallis cultivars and their biological activity
  89. Mechanical Properties of Carbon Fiber Reinforced Nanocrystalline Nickel Composite Electroforming Deposit
  90. Anti-c-myc efficacy block EGFL7 induced prolactinoma tumorigenesis
  91. Topical Issue on Applications of Mathematics in Chemistry
  92. Zagreb Connection Number Index of Nanotubes and Regular Hexagonal Lattice
  93. The Sanskruti index of trees and unicyclic graphs
  94. Valency-based molecular descriptors of Bakelite network BNmn
  95. Computing Topological Indices for Para-Line Graphs of Anthracene
  96. Zagreb Polynomials and redefined Zagreb indices of Dendrimers and Polyomino Chains
  97. Topological Descriptor of 2-Dimensional Silicon Carbons and Their Applications
  98. Topological invariants for the line graphs of some classes of graphs
  99. Words for maximal Subgroups of Fi24‘
  100. Generators of Maximal Subgroups of Harada-Norton and some Linear Groups
  101. Special Issue on POKOCHA 2018
  102. Influence of Production Parameters on the Content of Polyphenolic Compounds in Extruded Porridge Enriched with Chokeberry Fruit (Aronia melanocarpa (Michx.) Elliott)
  103. Effects of Supercritical Carbon Dioxide Extraction (SC-CO2) on the content of tiliroside in the extracts from Tilia L. flowers
  104. Impact of xanthan gum addition on phenolic acids composition and selected properties of new gluten-free maize-field bean pasta
  105. Impact of storage temperature and time on Moldavian dragonhead oil – spectroscopic and chemometric analysis
  106. The effect of selected substances on the stability of standard solutions in voltammetric analysis of ascorbic acid in fruit juices
  107. Determination of the content of Pb, Cd, Cu, Zn in dairy products from various regions of Poland
  108. Special Issue on IC3PE 2018 Conference
  109. The Photocatalytic Activity of Zns-TiO2 on a Carbon Fiber Prepared by Chemical Bath Deposition
  110. N-octyl chitosan derivatives as amphiphilic carrier agents for herbicide formulations
  111. Kinetics and Mechanistic Study of Hydrolysis of Adenosine Monophosphate Disodium Salt (AMPNa2) in Acidic and Alkaline Media
  112. Antimalarial Activity of Andrographis Paniculata Ness‘s N-hexane Extract and Its Major Compounds
  113. Special Issue on ABB2018 Conference
  114. Special Issue on ICCESEN 2017
  115. Theoretical Diagnostics of Second and Third-order Hyperpolarizabilities of Several Acid Derivatives
  116. Determination of Gamma Rays Efficiency Against Rhizoctonia solani in Potatoes
  117. Studies On Compatibilization Of Recycled Polyethylene/Thermoplastic Starch Blends By Using Different Compatibilizer
  118. Liquid−Liquid Extraction of Linalool from Methyl Eugenol with 1-Ethyl-3-methylimidazolium Hydrogen Sulfate [EMIM][HSO4] Ionic Liquid
  119. Synthesis of Graphene Oxide Through Ultrasonic Assisted Electrochemical Exfoliation
  120. Special Issue on ISCMP 2018
  121. Synthesis and antiproliferative evaluation of some 1,4-naphthoquinone derivatives against human cervical cancer cells
  122. The influence of the grafted aryl groups on the solvation properties of the graphyne and graphdiyne - a MD study
  123. Electrochemical modification of platinum and glassy carbon surfaces with pyridine layers and their use as complexing agents for copper (II) ions
  124. Effect of Electrospinning Process on Total Antioxidant Activity of Electrospun Nanofibers Containing Grape Seed Extract
  125. Effect Of Thermal Treatment Of Trepel At Temperature Range 800-1200˚C
  126. Topical Issue on Agriculture
  127. The effect of Cladophora glomerata exudates on the amino acid composition of Cladophora fracta and Rhizoclonium sp.
  128. Influence of the Static Magnetic Field and Algal Extract on the Germination of Soybean Seeds
  129. The use of UV-induced fluorescence for the assessment of homogeneity of granular mixtures
  130. The use of microorganisms as bio-fertilizers in the cultivation of white lupine
  131. Lyophilized apples on flax oil and ethyl esters of flax oil - stability and antioxidant evaluation
  132. Production of phosphorus biofertilizer based on the renewable materials in large laboratory scale
  133. Human health risk assessment of potential toxic elements in paddy soil and rice (Oryza sativa) from Ugbawka fields, Enugu, Nigeria
  134. Recovery of phosphates(V) from wastewaters of different chemical composition
  135. Special Issue on the 4th Green Chemistry 2018
  136. Dead zone for hydrogenation of propylene reaction carried out on commercial catalyst pellets
  137. Improved thermally stable oligoetherols from 6-aminouracil, ethylene carbonate and boric acid
  138. The role of a chemical loop in removal of hazardous contaminants from coke oven wastewater during its treatment
  139. Combating paraben pollution in surface waters with a variety of photocatalyzed systems: Looking for the most efficient technology
  140. Special Issue on Chemistry Today for Tomorrow 2019
  141. Applying Discriminant and Cluster Analyses to Separate Allergenic from Non-allergenic Proteins
  142. Chemometric Expertise Of Clinical Monitoring Data Of Prolactinoma Patients
  143. Chemomertic Risk Assessment of Soil Pollution
  144. New composite sorbent for speciation analysis of soluble chromium in textiles
  145. Photocatalytic activity of NiFe2O4 and Zn0.5Ni0.5Fe2O4 modified by Eu(III) and Tb(III) for decomposition of Malachite Green
  146. Photophysical and antibacterial activity of light-activated quaternary eosin Y
  147. Spectral properties and biological activity of La(III) and Nd(III) Monensinates
  148. Special Issue on Monitoring, Risk Assessment and Sustainable Management for the Exposure to Environmental Toxins
  149. Soil organic carbon mineralization in relation to microbial dynamics in subtropical red soils dominated by differently sized aggregates
  150. A potential reusable fluorescent aptasensor based on magnetic nanoparticles for ochratoxin A analysis
  151. Special Issue on 13th JCC 2018
  152. Fluorescence study of 5-nitroisatin Schiff base immobilized on SBA-15 for sensing Fe3+
  153. Thermal and Morphology Properties of Cellulose Nanofiber from TEMPO-oxidized Lower part of Empty Fruit Bunches (LEFB)
  154. Encapsulation of Vitamin C in Sesame Liposomes: Computational and Experimental Studies
  155. A comparative study of the utilization of synthetic foaming agent and aluminum powder as pore-forming agents in lightweight geopolymer synthesis
  156. Synthesis of high surface area mesoporous silica SBA-15 by adjusting hydrothermal treatment time and the amount of polyvinyl alcohol
  157. Review of large-pore mesostructured cellular foam (MCF) silica and its applications
  158. Ion Exchange of Benzoate in Ni-Al-Benzoate Layered Double Hydroxide by Amoxicillin
  159. Synthesis And Characterization Of CoMo/Mordenite Catalyst For Hydrotreatment Of Lignin Compound Models
  160. Production of Biodiesel from Nyamplung (Calophyllum inophyllum L.) using Microwave with CaO Catalyst from Eggshell Waste: Optimization of Transesterification Process Parameters
  161. The Study of the Optical Properties of C60 Fullerene in Different Organic Solvents
  162. Composite Material Consisting of HKUST-1 and Indonesian Activated Natural Zeolite and its Application in CO2 Capture
  163. Topical Issue on Environmental Chemistry
  164. Ionic liquids modified cobalt/ZSM-5 as a highly efficient catalyst for enhancing the selectivity towards KA oil in the aerobic oxidation of cyclohexane
  165. Application of Thermal Resistant Gemini Surfactants in Highly Thixotropic Water-in-oil Drilling Fluid System
  166. Screening Study on Rheological Behavior and Phase Transition Point of Polymer-containing Fluids produced under the Oil Freezing Point Temperature
  167. The Chemical Softening Effect and Mechanism of Low Rank Coal Soaked in Alkaline Solution
  168. The Influence Of NO/O2 On The NOx Storage Properties Over A Pt-Ba-Ce/γ-Al2O3 Catalyst
  169. Special Issue on the International conference CosCI 2018
  170. Design of SiO2/TiO2 that Synergistically Increases The Hydrophobicity of Methyltrimethoxysilane Coated Glass
  171. Antidiabetes and Antioxidant agents from Clausena excavata root as medicinal plant of Myanmar
  172. Development of a Gold Immunochromatographic Assay Method Using Candida Biofilm Antigen as a Bioreceptor for Candidiasis in Rats
  173. Special Issue on Applied Biochemistry and Biotechnology 2019
  174. Adsorption of copper ions on Magnolia officinalis residues after solid-phase fermentation with Phanerochaete chrysosporium
  175. Erratum
  176. Erratum to: Sand Dune Characterization For Preparing Metallurgical Grade Silicon
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Heruntergeladen am 20.12.2025 von https://www.degruyterbrill.com/document/doi/10.1515/chem-2019-0008/html
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