Fabrication of fritless chromatographic microchips packed with conventional reversed-phase silica particles.

This paper describes the development and study of a disposable and inexpensive microfluidic chip, fabricated from poly(dimethylsiloxane) (PDMS) incorporating conventional chromatographic reversed-phase silica particles (C18) without the use of frits, permanent physical barriers, tapers, or restrictors. The packing of C18 modified silica particles into the microfluidic channels is made possible by the hydrophobic nature and excellent elasticity of PDMS. Keystone-, clamping-, and anchor-effects provide the stability and the compactness of the packing and attenuated wall-effects were observed.