Home Medicine From “wet” matrices to “dry” blood spot sampling strategy: a versatile LC-MS/MS assay for simultaneous monitoring caffeine and its three primary metabolites in preterm infants
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From “wet” matrices to “dry” blood spot sampling strategy: a versatile LC-MS/MS assay for simultaneous monitoring caffeine and its three primary metabolites in preterm infants

  • Hao-Ran Dai ORCID logo , Hong-Li Guo , Wei-Jun Wang , Xian Shen , Rui Cheng , Jing Xu , Ya-Hui Hu EMAIL logo , Xuan-Sheng Ding EMAIL logo and Feng Chen ORCID logo EMAIL logo
Published/Copyright: July 13, 2023
Clinical Chemistry and Laboratory Medicine (CCLM)
From the journal Clinical Chemistry and Laboratory Medicine (CCLM) Volume 62 Issue 1

Abstract

Objectives

To update traditional “wet” matrices to dried blood spot (DBS) sampling, based on the liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) technique, and develop a method for simultaneous analyzing caffeine and its three primary metabolites (theobromine, paraxanthine, and theophylline), supporting routine therapeutic drug monitoring (TDM) for preterm infants.

Methods

DBS samples were prepared by a two-step quantitative sampling method, i.e., volumetric sampling of a quantitative 10 μL volume of peripheral blood and an 8 mm diameter whole punch extraction by a methanol/water (80/20, v/v) mixture containing 125 mM formic acid. Four paired stable isotope labeled internal standards and a collision energy defect strategy were applied for the method optimization. The method was fully validated following international guidelines and industrial recommendations on DBS analysis. Cross validation with previously developed plasma method was also proceeded. The validated method was then implemented on the TDM for preterm infants.

Results

The two-step quantitative sampling strategy and a high recovery extraction method were developed and optimized. The method validation results were all within the acceptable criteria. Satisfactory parallelism, concordance, and correlation were observed between DBS and plasma concentrations of the four analytes. The method was applied to provide routine TDM services to 20 preterm infants.

Conclusions

A versatile LC-MS/MS platform for simultaneous monitoring caffeine and its three primary metabolites was developed, fully validated, and successfully applied into the routine clinical TDM practices. Sampling method switching from “wet” matrices to “dry” DBS will facilitate and support the precision dosing of caffeine for preterm infants.

Keywords: caffeine; dried blood spot; LC-MS/MS; preterm infants; therapeutic drug monitoring
Corresponding authors: Ya-Hui Hu, Pharmaceutical Sciences Research Center, Department of Pharmacy, Children’s Hospital of Nanjing Medical University, 72 Guangzhou Road, Nanjing 210008, P.R. China, E-mail: ; Xuan-Sheng Ding, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, 639 Longmian Avenue, Nanjing 211198, P.R. China, E-mail: ; and Feng Chen, Department of Pharmacy, Pharmaceutical Sciences Research Center, Children’s Hospital of Nanjing Medical University, 72 Guangzhou Road, Nanjing 210008, P.R. China, E-mail:
Hao-Ran Dai and Wei-Jun Wang are visiting graduate students from China Pharmaceutical University.

Funding source: Specially Appointed Medical Expert Project of the Jiangsu Commission of Health

Award Identifier / Grant number: 2019

Funding source: Scientific Research Support Foundation for Top Young Scholars at the Children’s Hospital of Nanjing Medical University

Award Identifier / Grant number: 2020

Funding source: Special Fund for Clinical Research of the Wu Jieping Medical Foundation

Award Identifier / Grant number: 320.6750.2020-04-07

Acknowledgments

The authors would like to thank the two anonymous reviewers for their constructive critical remarks and the editors of Clinical Chemistry and Laboratory Medicine for their kind suggestions and assistance along with all of the authors of the previous works that we referenced. These contributions helped significantly to refine and improve the content and the presentation of the paper.

  1. Research funding: This work was supported by the Specially Appointed Medical Expert Project of the Jiangsu Commission of Health (2019) and Special Fund for Clinical Research of the Wu Jieping Medical Foundation (320.6750.2020-04-07). This study was also supported by the Scientific Research Support Foundation for Top Young Scholars at the Children’s Hospital of Nanjing Medical University (2020).

  2. Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.

  3. Competing interests: Authors state no conflict of interest.

  4. Informed consent: Informed consent was not required to participate in this study in accordance with the national legislation and the institutional requirements.

  5. Ethical approval: Research involving human subjects complied with all relevant national regulations, institutional policies and is in accordance with the tenets of the Helsinki Declaration (as revised in 2013), and has been approved by the authors’ Institutional Review Board (202012146-1).

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Supplementary Material

This article contains supplementary material (https://doi.org/10.1515/cclm-2023-0310).

Received: 2023-03-27
Accepted: 2023-07-04
Published Online: 2023-07-13
Published in Print: 2024-01-26

© 2023 Walter de Gruyter GmbH, Berlin/Boston

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https://doi.org/10.1515/cclm-2023-0310
Keywords for this article
caffeine; dried blood spot; LC-MS/MS; preterm infants; therapeutic drug monitoring

Articles in the same Issue

  1. Frontmatter
  2. Editorial
  3. Biological management of diabetes mellitus, the laboratory medicine specialist and the patient
  4. Reviews
  5. Remote HbA1c testing via microsampling: fit for purpose?
  6. The effect of hormonal contraceptive therapy on clinical laboratory parameters: a literature review
  7. Opinion Paper
  8. Continuous glucose monitoring has an increasing role in pre-symptomatic type 1 diabetes: advantages, limitations, and comparisons with laboratory-based testing
  9. IFCC Paper
  10. Comparison and commutability study among four faecal immunochemical tests (FIT) systems
  11. Guidelines and Recommendations
  12. Evidence-based procedures to improve the reliability of circulating miRNA biomarker assays
  13. General Clinical Chemistry and Laboratory Medicine
  14. Commutability assessment of candidate reference materials for plasma renin activity measurement: current challenges
  15. Aggregated data from the same laboratories participating in two glucose external quality assessment schemes show that commutability and transfers of values to control materials are decisive for the biases found
  16. Methodological considerations in determining sex steroids in children: comparison of conventional immunoassays with liquid chromatography-tandem mass spectrometry
  17. From “wet” matrices to “dry” blood spot sampling strategy: a versatile LC-MS/MS assay for simultaneous monitoring caffeine and its three primary metabolites in preterm infants
  18. A sensitive LC-MS/MS methotrexate assay capable of assessing adherence to methotrexate therapy in rheumatoid arthritis
  19. Determination of cortisone and cortisol in human scalp hair using an improved LC-MS/MS-based method
  20. Mild hypophosphatasia may be twice as prevalent as previously estimated: an effective clinical algorithm to detect undiagnosed cases
  21. Combined deficient response to polysaccharide-based and protein-based vaccines predicts a severe clinical phenotype
  22. Reference Values and Biological Variations
  23. A sex-specific association of leukocyte telomere length with thigh muscle mass
  24. Cancer Diagnostics
  25. Optimized procedure for high-throughput transcriptome profiling of small extracellular vesicles isolated from low volume serum samples
  26. Ultra-short cell-free DNA fragments enhance cancer early detection in a multi-analyte blood test combining mutation, protein and fragmentomics
  27. Clinical relevance of clonal hematopoiesis and its interference in cell-free DNA profiling of patients with gastric cancer
  28. Development and analytical validation of a novel nasopharynx swab-based Epstein-Barr virus C promoter methylation quantitative assay for nasopharyngeal carcinoma detection
  29. Infectious Diseases
  30. (Pre)analytical considerations concerning the analysis of synovial calprotectin
  31. Corrigendum
  32. Thermal and chronological stability of monocyte distribution width (MDW), the new biomarker for sepsis
  33. Acknowledgment
  34. Acknowledgment
  35. Letters to the Editor
  36. In-house diagnostic devices under the EU IVDR and unwanted side-effects of intentional transparency
  37. Use of thyroid function tests in urine: a position statement of the Belgian Thyroid Club
  38. State of the art of measurement uncertainty of serum ferritin
  39. Analytical performance evaluation and consumable waste reduction strategies using a tube-based quality control material
  40. Stability of fecal calprotectin extracts using the Diasorin® kit
  41. Reverse cascade testing from newborn screening: the opportunity to improve family healthcare outcomes
  42. An indirect data-mining approach to standardise paediatric serum phosphate reference intervals in Wales
  43. Sodium and risk assessment of osmotic demyelination syndrome: the method matters!
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