A microfluidic chip with poly(ethylene glycol) hydrogel microarray on nanoporous alumina membrane for cell patterning and drug testing

In this paper, a microfluidic silicon chip with poly(ethylene glycol) (PEG) hydrogel microarray on the nanoporous anodized aluminum oxide (AAO) membrane was fabricated to form cell based microarray with controlled drug delivery. The PEG hydrogel microstructures were fabricated using photolithography on nanoporous alumina surface modified with a 3-(trimethoxysilyl)propyl methacrylate (TPM) monolayer. During the photopolymerization reaction, 10 × 10 hydrogel microwell arrays were covalently bonded to the substrate via the TPM monolayer for cell patterning. Human KYSE-30 esophageal squamous epithelial cancer cells were shown to selectively adhere on the TPM modified alumina surface inside the microwells. The diffusion studies for anti-cancer drug molecule of cisplatin were carried out for the microfabricated membrane array using a mini-diffusion chamber. The diffusion curves for pore size of 25 nm and 55 nm showed different release profiles. Then, the drug testing experiment with cisplatin was explored using the microfabricated membrane array with pore size of 55 nm for testing the drug effects on the KYSE-30 cancer cells. The cytotoxic effects of cisplatin on cancer cell number and cell morphology within microwells were explored based on this cell microarray.