title: The use of poly(dimethylsiloxane) surface modification with gold nanoparticles for the microchip electrophoresis.
abstract: Poly(dimethylsiloxane) (PDMS) microfluidic channels modified by citrate-stabilized gold nanoparticles after coating a layer of linear polyethylenimine (LPEI) were successfully used to separate dopamine and epinephrine, which were difficult to be separated from baseline in native and hybrid PDMS microchannels. In-channel amperometric detection with a single carbon fibre cylindrical electrode was employed. Experimental parameters of separation and detection processes were optimized in detail. The analytes were well separated within 100 s in a 3.7 cm long separation channel at a separation voltage of +800 V using a 30 mM phosphate buffer solution (PBS, pH 7.0). Linear responses of them were obtained both from 25 to 600 microM with detection limits of 2 microM for dopamine and 5 microM for epinephrine, respectively. The modified PDMS channels have a long-term stability and an excellent reproducibility within 2 weeks.
authors.affiliation: Key Lab of Analytical Chemistry for Life Science, Department of Chemistry, Nanjing University, Nanjing, PR China.
authors.forename: Ai-Jun
authors.initials: AJ
authors.lastname: Wang
authors.forename: Jing-Juan
authors.initials: JJ
authors.lastname: Xu
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhang
authors.forename: Hong-Yuan
authors.initials: HY
authors.lastname: Chen