Simple patterned nanofiber scaffolds and its enhanced performance in immunoassay.

Cancer has become the leading cause of death worldwide; early diagnosis and treatment of cancers is critical for the survival of the patients. The concentration of cancer markers in easy-to-access biological fluids can provide great assistance in screening for occult primary cancers, distinguishing malignant from benign findings, determining prognosis and prediction for cancer patients. The multiplex detection technology of a panel of cancer markers can greatly increase the accuracy of disease diagnosis.

A 3D porous polymer monolith-based platform integrated in poly(dimethylsiloxane) microchips for immunoassay.

In this work, we demonstrate the immunocapture and on-line fluorescence immunoassay of protein and virus based on porous polymer monoliths (PPM) in microfluidic devices. Poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) [poly(GMA-co-EGDMA)] monoliths were successfully synthesized in the polydimethylsiloxane (PDMS) microfluidic channels by in situ UV-initiated free radical polymerization. After surface modification, PPM provides a high-surface area and specific affinity 3D substrate for immunoassays.

Microchip-based immunoassays with application of silicon dioxide nanoparticle film.

Highly sensitive detection of proteins offers the possibility of early and rapid diagnosis of various diseases. Microchip-based immunoassay integrates the benefits from both immunoassays (high specificity of target sample) and microfluidics (fast analysis and low sample consumption). However, direct capture of proteins on bare microchannel surface suffers from low sensitivity due to the low capacity of microsystem.

Polymer monolith-integrated multilayer poly(dimethylsiloxane) microchip for online microextraction and capillary electrophoresis.

We reported the in situ synthesis and use of porous polymer monolith (PPM) columns in an integrated multilayer PDMS/glass microchip for microvalve-assisted on-line microextraction and microchip electrophoresis for the first time. Under the control of PDMS microvalves, the grafting of the microchannel surface and in situ photopolymerization of poly(methacrylic acid-co-ethylene glycol dimethacrylate) monolith in a defined zone were successfully achieved. Different factors including the surface grafting, polymerization time, PDMS elastic properties (ratio of oligomer/curing reagent) and UV intensity that affect the monolith synthesis in the PDMS microchannel were investigated and optimized.