Flame aerosol deposition of TiO_2 nanoparticle films on polymers and polymeric microfluidic devices for on-chip phosphopeptide enrichment

摘要

Direct and fast (10s of seconds) deposition of flame-made, high surface-area aerosol films on polymers and polymeric microfluidic devices is demonstrated. Uniform TiO_2 nanoparticle films were deposited on cooled poly(methyl methacrylate) (PMMA) substrates by combustion of titanium(IV) isopropoxide (TTIP) - xylene solution sprays. Films were mechanically stabilized by in situ annealing with a xylene spray flame. Plasma-etched microfluidic chromatography columns, comprising parallel microchannels were also coated with such nanoparticle films without any microchannel deformation. These microcol-umns were successfully used in metaloxide affinity chromatography (MOAC) to selectively trap phospho-peptides on these high surface-area nanostructured films. The chips had a high capacity retaining 1.2 ug of standard phosphopeptide. A new extremely fast method is developed for MOAC microchip stationary phase fabrication with applications in proteomics.