Surface Modification of Poly(methyl methacrylate) Used in the Fabrication of Microanalytical Devices

Abstract

We report here the chemical modification of poly(methyl methacrylate) (PMMA) surfaces by their reaction with the monoanion of alpha,omega-diaminoalkanes (aminolysis reaction) to yield amine-terminated PMMA surfaces. It is found that the amine functionalities are tethered to the PMMA backbone through an alkane bridge to amide bonds formed during the aminolysis of the surface ester functionalities. The distribution of the amine termini is quite uniform as judged by fluorescence micrographs. It is found that the electroosmotic flow in aminated PMMA microchannels is reversed when compared to that in unmodified channels. In addition, it is demonstrated that enzymes can be immobilized onto the amine-terminated PMMA surfaces and are effective in the restriction digestion of dsDNAs. Finally, the availability of the surface amine groups is further demonstrated by their reaction with n-octadecane-1-isocyanate to form PMMA surfaces terminated with well-ordered and highly crystalline octadecane chains.

Integration of a flow-type chemiluminescence detector on a glass electrophoresis chip

“…Over the past decade, -TAS has experienced the phenomenal success and displayed enormous practical potentials [3,4]. These devices can integrate diversely functional units to accomplish screening of large sample populations or processing of special kinds of samples.…”

Surface modification in microchip electrophoresis

“…Chemical modification of PMMA via aminolyses of surface esters to yield amine-terminated PMMA surfaces was reported by Henry et al [83]. The EOF in such aminated PMMA microchannels was reversed compared to unmodified substrates.…”

Modification of a poly(methyl methacrylate) injection-molded microchip and its use for high performance analysis of DNA

“…However, the development of routine, simple, and well-defined surface modification protocols for polymers is still in its infancy [19]. PMMA-based microfluidic devices are time-consuming and complicated [16 -18].…”

“…Solving this problem of the microchannel inner surfaces is very important for improving the separation effect. In fact, some researchers have developed specials coatings or coated PMMA separation channel with nonionic surfactants [17] or by surface chemical modification [18,19]. However, the modification methods mentioned above for the inner surfaces of plastic microdevice channels have two main disadvantages: they are time-consuming and give unstable inner surfaces.…”

“…However, the modification methods mentioned above for the inner surfaces of plastic microdevice channels have two main disadvantages: they are time-consuming and give unstable inner surfaces. Thus, the development of routine, simple, stable surface modification protocols for polymers is still in its infancy [19].…”