Slump Molding of Microchannel Arrays in Soda-Lime Glass for Bioanalytical Device Development

Abstract

A slump molding process was developed to place microchannel geometries in a soda-lime glass substrate for a lab-on-chip bioanalytical device. The process was developed to overcome the biological and chemical reactivity associated with current polymer lab-on-a-chip substrates, and as an alternative to using more expensive glass material. A high speed micro mill and UV laser micromachining center were used to fabricate the negative geometries in the graphite mold material that was used. The slumping process of the soda-lime glass was done using a glass kiln. Microchannel dimensions were in the mesa scale range of 50 μm width × 10 μm depth. The heating schedule for slump molding of the soda-lime glass to take its final shape to these dimensions was determined and documented. The functionality of the slumping process and resultant soda-lime glass device was validated through murine nerve tissue experiments conducted through the bioanalytical device that was developed. The research represented a novel use of slump molding, a process traditionally known for producing artistic works for: (a) embossing engineered microchannels and (b) reliably processing a soda-lime glass substrate, a material known to be difficult to work with due to its poor physical properties.