Greening Capillary Electrophoresis, a promising sprout of Separation Science toward sustainability

Abstract

As a result of miniaturization new avenues were open toward customizing, improving and rendering separation science more affordable and available to any laboratory worldwide. One of the best resolving liquid separation techniques that still benefits from miniaturization is capillary electrophoresis (CE), where analytes are separated by their hydrodynamic volume to charge ratio. The theory of CE was introduced almost one hundred years ago, but became popular in the 1970s, yielding by 2010 over 1000 papers produced yearly. This progress triggered sample preparation optimization efforts, which led to significant reduction of required chemicals for analysis and the decrease of overall sample processing times. Consequently, CE can be considered as a sustainable technique in the field of liquid phase separation science. In this paper a custom made, cheap capillary electrophoresis unit with LED induced fluorescent (LedIF) imaging detection was used to demonstrate applicability of modern electronics, consumer products, and 3D printing in generating scientific results, while keeping sustainability in mind. Samples were chosen according to the observed trends of the past decade, namely from biotherapeutics industry. Its golden standard, immunoglobulin G N-glycans were enzymatically digested and the released complex type oligosaccharides were labeled with charged fluorophore, according to one of the most advanced and optimized protocols. Results were compared to separation runs performed on a high quality commercially available instrument, used as the control. Results disclosed in this paper should not be subjected to direct quantitative comparison, but should be rather taken as a technical demonstration of the capabilities of current and future technology, which can be implemented and merged with existing solutions in a sustainable manner.