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.

Determination of complex type free, non‐conjugated oligosaccharide glucose unit values in tomato xylem sap for early detection of nutrient deficiency

“…Three‐stage sample injection was utilized: (1) pressure‐assisted water injection at 1 psi, for 5 s, (2) electrokinetic sample injection at 3 kV, for 3 s, and (3) APTS‐labeled maltose (GU = 2) internal standard was injected at 1 kV, for 1 s. High resolution N ‐linked Carbohydrate Separation gel buffer (HR‐NCHO) from the kit (SCIEX) served as the background electrolyte, and the 32Karat software package (version 9.2, SCIEX) was used for data acquisition and processing. GU calculations were completed with GUcal v1.1B software (gucal.hu), with the internal standard option as the basis of glycosylation analysis for all sample components of interest (peaks) in the healthy and nutrient deficient electropherograms [27–31]. Relative percentage area values of the separated peaks were calculated by means of PeakFit v4.12 software (SeaSolve Software Inc., San Jose, CA).…”

Applications of capillary electrophoresis for biopharmaceutical product characterization

“…The approach expanded the dynamic range for CE‐based separations and demonstrated the applicability of the method to generate evaluable and quantifiable signals for glycans derived from 0.2 mg/ml of IgG and up to 35 mg/ml maltooligosaccharide ladder samples. The sustainability of CE with LedIF detection for glycan analysis was also shown on a semi‐automated home‐built CE device with results comparable to a fully automated commercial CE system [76]. Both systems were capable to detect 13 glycans.…”

“…Method developments in mAb glycosylation analysis using CE were reported using commercial human IgG as the model sample [74][75][76][77][78][79][80][81][82]. For example, in one study, the hardware components of the CE instrument itself were used to develop semi and fully automated CE-LIF-based methods for carbohydrate sequencing of released glycans [74].…”

Virus and peace: a concerned editorial

“…Samples were chosen from biotherapeutics industry. Results disclosed in this paper can serve as a demonstration of technical capabilities of current and future CE technique, which can be implemented and merged with existing solutions in a sustainable manner (Szarka, 2020).…”