Integration of patterned photonic nitrocellulose and microfluidic chip for fluorescent point-of-care testing of multiple targets
A microfluidic chip based on patterned photonic nitrocellulose is presented to perform a sensitive multiplex fluoroimmunoassay of 3 targets. The microfluidic chip is composed of a PDMS sheet with microchannel and a patterned photonic nitrocellulose. The patterned SiO2 colloidal photonic crystal (opal structure) is first prepared as the template for the patterned photonic nitrocellulose. The inverse-opal structure of the patterned photonic nitrocellulose can largely amplify fluorescence signals due to the “slow photon” effect, while the microfluidic design can reduce the sample and reagent consumption, thus resulting in a highly efficient and cost-effective microfluidic chip. The gas solubility/permeability of PDMS is utilized to conduct vacuum-driven liquid introduction into the microfluidic chip. Multiplex fluoroimmunoassay of AFP, MYO and CK-MB is demonstrated by the microfluidic chip.