Protein immobilization on the surface of polydimethylsiloxane and polymethyl methacrylate microfluidic devices

Abstract

PDMS and PMMA are two of the most used polymers in the fabrication of lab-on-chip or microfluidic devices. In order to use these polymers in biological applications, it is sometimes essential to be able to bind biomolecules such as proteins and DNA to the surface of these materials. In this work, we have evaluated a number of processes that have been developed to bind protein to PDMS surfaces which include passive adsorption, passive adsorption with glutaraldehyde cross-linking, (3-aminopropyl) triethoxysilane functionalization followed by glutaraldehyde or 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride cross-linkers. It has been shown that the latter technique--using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride--results in more than twice the bonding of protein to the surface of PDMS microchannels than proteins binding passively. We have also evaluated a few techniques that have been tested for the functionalization of PMMA microchannels where we have found that the use of polyethyleneimine (PEI) has led to the strongest protein-PMMA microchannel bond. We finally demonstrated the effect of PDMS curing methodology on protein adsorption to its surface, and showed that increased curing time is the factor that reduces passive adsorption the most.

Polyelectrolyte Coatings—A Viable Approach for Cultural Heritage Protection

“…An et al reported a facile method for the construction of cross-linked polyelectrolyte multilayers using PSS/PAH by post-implantation and subsequent photochem [ 34 ]. PAH/PSS layer-by-layer assembly containing nanoporous silver submicrocubes were developed for electrochemical glucose sensing [ 35 ], while PEI/PAA polyelectrolyte multilayer architecture coated on PDMS conducted to long-term stability on the interface for protein detection [ 37 ].…”

Biofunctionalization of Glass‐ and Paper‐Based Microfluidic Devices: A Review

“…Amino groups can bind to the activated carboxylic groups of the proteins. Zero‐length carbodiimide cross‐linkers such as 1‐ethyl‐3‐(‐3‐dimethylaminopropyl) carbodiimide hydrochloride (EDC or EDAC) are usually used to activate the carboxylic groups by creating O‐acylisourea intermediate. They react rapidly to the amino groups of the surface producing isourea as a by‐product.…”

Surface Biochemical Modification of Poly(dimethylsiloxane) for Specific Immune Cytokine Response

“…Previous works, including ours, have followed a similar approach but were focused on silicon silanization and detection of different biological targets. 38,39,43 While some studies have been using APTES on PDMS without prior activation of the surface, 32,44 it has been shown that activating the PDMS surface right before silanization would increase the grafting efficiency. 45,46 To the best of our knowledge, no comprehensive study related to controllable and stable direct PDMS silanization by APTES has been proposed.…”

“…Only a minority of devices include a biosensitive surface inside a microfluidic channel as it requires a reproducible and stable surface chemistry for biomolecule conjugations. Silanization reactions have been shown to be a convincing method for PDMS bonding, − surface modification for molecular grafting, ,− or even for preventing biofouling . Silanization of PDMS relies on readily producible silanol groups for covalent bonding of silane molecules.…”