The development of a weak anion micro-capillary film for protein chromatography

Applications of microcapillary films in bioanalytical techniques

Microcapillary film (MCF) is an extruded plastic film with an array of parallel microcapillaries (30-500 μm) and it has wide potential applications in bioanalytical techniques as a microfluidic platform. With different surface modification strategies, an MCF combines the advantages of its structure and modified chemical properties to realize various bioanalytical functions. In this review, we begin by introducing the manufacturing process of MCFs, common materials used to produce MCFs, surface treatment approaches of inner surfaces, and a signal detection and readout system of the MCF platform. Then, we summarize some typical applications of MCFs, particularly in protein chromatography, Escherichia coli detection for urinary tract infections, prostate-specific antigen detection for prostate cancer and multiplex immunoassays. Finally, future perspectives of MCFs in bioanalytical techniques are discussed.

Development of a disposable micro-capillary film grafted with peptide ligands for immunoadsorption

Traditional chromatographic techniques used in downstream processes of biomolecule manufacturing are often time-consuming and expensive. In this study, a cost-effective microporous micro-capillary film (MMCF) composed of ethylenevinyl alcohol (EVOH) was evaluated for its potential application in immunoadsorption with high process efficiency. A peptide ligand Ac-Phe-Tyr-His-Glu (Ac-FYHE) was immobilized on the inner surface of MMCF for selective binding of human immunoglobulin (hIgG). The porous structure and chemical properties of the prepared MMCF were confirmed by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). hIgG (2 mg/ml) adsorption studies demonstrated that the binding process followed a Langmuir isotherm with equilibrium adsorption capacities of 9.31 and 3.47 mg/ml adsorbent under static and dynamic conditions, respectively. Moreover, the membrane showed good flowrate tolerance when studied under flowrates of 0.5 ml/min to 10 ml/min. hIgG purity was 88.2% when obtained from an hIgG (2 mg/ml) and HSA (8 mg/ml) mixture and the purity remained over 80.0% when hIgG concentrations increased in the mixtures. Moreover, purity of 82.3% was achieved when removing hIgG directly from human serum. The MMCF-Ac-FYHE affinity column is expected to selectively remove hIgG from blood for the treatment of autoimmune diseases with high efficiency and cost effectiveness.