A conjoint multi metal‐ion iminodiacetic acid monolith microfluidic chip for structural‐based protein pre‐fractionation

Abstract

PDMS‐based multichannel microfluidic chip was designed and fabricated in a simple approach using readily available tools. UV‐initiated in situ polymerization of poly(2‐hydroxy ethyl methacrylate‐co‐di(ethylene glycol) diacrylate‐co‐N,Nʹ‐diallyl l‐tartardiamide) in an Eppendorf tube was achieved within 40 min. This polymerization process was successfully translated to a microfluidic chip format without any further modifications. Iminodiacetic acid was successfully immobilized on aldehyde functional monoliths via Schiff base reaction and confirmed by FT‐IR spectroscopy. Four transition metal ions (Co (II), Zn (II), Ni (II), and Cu (II)) were chelated individually on four IDA‐monolith microfluidic chips. The conjoint metal‐ion monolith microfluidic chip has displayed high permeability (9.40 × 10–13 m2) and a porosity of 32.8%. This affinity microfluidic chip has pre‐fractioned four human plasma proteins (fibrinogen, immunoglobulin, transferrin, and human serum albumin) based on their surface‐exposed histidine surface topography. A protein recovery of approximately 95% (Bradford assay data) was achieved. The multimonolith microchip can be reusable even after three protein adsorption‐desorption cycles.

Recent stationary phase‐based fractionation strategies in proteomic analysis

“…One study reported the use of monolith as a support for IMAC metal cations [105]. A poly(2‐hydroxy ethyl methacrylate‐co‐di(ethylene glycol) diacrylate‐co‐ N,Nʹ ‐diallyl l‐tartardiamide monolith prepared inside a PDMS microchip had the aldehyde functional groups modified with iminodiacetic acid to chelate Co (II), Zn (II), Ni (II), and Cu (II) and perform IMAC enrichment.…”

“…The monolith‐integrated microfluidic chip could pre‐fractionate four human plasma proteins (fibrinogen, immunoglobulin, transferrin, and human serum albumin) based on their surface‐exposed histidine. LC‐MS/MS detection on the second dimension wasn´t performed, but a determination by Bradford assay showed a protein recovery of approximately 95%, and the reutilization of the device was demonstrated after 3 adsorption‐desorption cycles [105].…”

“…One study reported the use of monolith as a support for IMAC metal cations [105]. albumin) based on their surface-exposed histidine.…”

“…albumin) based on their surface-exposed histidine. LC-MS/MS detection on the second dimension wasnťt performed, but a determination by Bradford assay showed a protein recovery of approximately 95%, and the reutilization of the device was demonstrated after 3 adsorptiondesorption cycles [105]. Two works from the same research group were dedicated to the tailoring of novel nanoparticles with improved capacities of enrichment of phosphopeptides and glycopeptides [106,107].…”