Laser-machined microfluidic bioreactors with printed scaffolds and integrated optical waveguides

Abstract

Laser micromachining combined with digital printing allows rapid prototyping of complex bioreactors with reduced fabrication times compared to multi-mask photolithography. Microfluidic bioreactors with integrated optical waveguides for diagnostics have been fabricated via ultrashort pulse laser micromachining and digital printing. The microfluidic channels are directly laser machined into poly(dimethylsiloxane) (PDMS) silicone elastomer. Multimode optical waveguides are formed by coating the PDMS with alternating refractive index polymer layers and laser machining to define the waveguide geometry. Tapered alignment grooves are also laser machined to aid in coupling optical fibers to the waveguides. Three-dimensional (3-D) bio-scaffold matrices comprising liquid solutions that can be selectively and rapidly gelled are digitally printed inside the bioreactors and filled with nutrient rich media and cells. This paper will describe the maskless fabrication of complex 3-D bioreactors and discuss their performance characteristics.