iX-factory GmbH: development of a microfluidic chromatography chip

Miniaturization of liquid chromatography

In recent years, the demand for miniaturization in analytical chemistry has risen [1]. The reason for its tremendous growth is that the application of microchips offers many advantages. Miniaturization allows reduction in costs, lower ancillary sample volume and sensitive measurements within a shorter span of time. Thus, time per analysis can be significantly lowered and the amount of chemical waste can be reduced.

Project

As a specialized technical service provider of MEMS (Microelectromechanical systems) and NEMS (Nanoelectromechanical systems) products, iX-factory GmbH was involved in the cooperation program “Phase-optimized chip-chromatography (POP-LC-Chip)” by Professor Belder of the University of Leipzig. The program was financed through ZIM (Zentrales Innovationsprogramm Mittelstand Cooperation Program, financed by the Federal Ministry of Economic Affairs and Energy). iX-factory developed and fabricated a specifically created microfluidic glass chip for high performance liquid chromatography (HPLC).

Using multidisciplinary technologies like wet-etching and thermal direct bonding, iX-factory fabricated a borosilicate glass chip with tailor-made column dimensions. The chip features two different channel depths, which allow the retention of particles in the designated column area according to the keystone effect. The channel has a width of 90 μm and a depth of 40 μm. At the constrictions, the fluidic channel is only 10 μm high. This narrowing allows the retention of 2.2 μm particles. The developed chip design by iX-factory – adapted to particle size, length of the column and the positioning of the columns in the chip – permits efficient separations of complex sample mixtures within the chip. The University of Leipzig performed a variety of tests with the HPLC chip. The results showed that complex samples can be examined in a few seconds without using complex eluent-mixed systems. Through the chip-chromatography, 80,000 separation stages/m are possible in a 5 cm long HPLC column. By contrast, the separation performance of conventional techniques lies between 20,000 and 60,000. This result shows that in terms of signal to sample volume, chip-chromatography makes faster and more sensitive analytical chemistry possible.

Left image: fluidic chromatographic chip with electrospray ionisation injection; sketch in the middle: draft of channel; right image: fluidic chromatographic chip with side inlet of glass capillaries

Company

Specified chip holder for innovating integrated valves on microfluidic chips

iX-factory GmbH is known for customized solutions. The company is a leading technical service provider of MEMS/NEMS and microfluidic products and offers the following services: personal expert advice, fabrication and project work, MEMS Foundry Service and the world around the chip. The company supports its customers in the development and fabrication of microchips of glass and/or silicon. Next to the chips, iX-factory offers the ideal connection and periphery to assure the perfect integration of the chip in the customer’s system. The company disposes, amongst others, the following processes: connecting the chip via chip holder or via glued in or welded on capillaries. Additionally, customers can book workshops and individual trainings. Through multidisciplinary technologies in the company’s state-of-the-art clean room, iX-factory delivers customized solutions with maximum professionalism, individualism and innovation. In order to meet the customer’s requirements, iX-factory offers the following technologies: dry etching, wet etching, wafer bonding, micropowder blasting, lithography, plasma deposition, furnace processes, metallization, metrology and backend processes. Along the entire processes, iX-factory assigns utmost importance to delivering high quality. Dependent on the functionality of the chip, the technologies are chosen. The ISO 9001 certification corroborates the high quality standards of iX-factory. Additionally, iX-factory guarantees 100% IP-security to its customers.

Microchips of glass and silicon offer many advantages to the customers. In chemistry, iX-factory realizes parallelization and automation of processes within the chip, as well as, precise control of sensitive process parameters. Using glass and silicon for the fabrication allows the manufacture of chips that are durable, replicable and biological. Moreover, the application of microchips allows the retirement of more reliable results within a shorter span of time. Meanwhile, the quantity of the sample is reduced.

Cooperations

Microreactor for flow chemistry reaction

As a specialist in MEMS, BioMEMS, Lab-on-a-Chip, microreactors and integrated optics, iX-factory offers customized solutions to universities, institutes and organization of various branches. During recent years, iX-factory was engaged in different notable projects which significantly contributed to the research and development in analytical chemistry, medical engineering and biotechnology. The project POP-LC-Chip is one example that microsystems technology has an immense impact on the development of other branches like, e.g., chemistry. The project “Development of leukaemia diagnostics in a microsystem based on clinical methods for the diagnostic of acute leukaemia” of iX-factory, together with the University of Applied Sciences Hamm-Lippstadt, is another example. In the future, iX-factory is looking forward to discovering more application areas and aims to support its customers in research and development, as well as in their success.

Funding: Federal Ministry for Economic Affairs and Energy, Germany, (Grant/Award Number: ‘KF2578402BN0’).