Chitosan cushioned phospholipid membrane and its application in imaging ellipsometry based-biosensor

Chitosan cushion can support the air stability of phospholipid membrane, but the problem of serum solubility of phospholipid membrane prevents it from use in serum detection applications. Poly (ethylene glycol) (PEG) shielding promises both stability and non-specific adsorption resistance for phospholipid membrane. An air stable phospholipid membrane microarray has been successfully fabricated on chitosan modified silicon wafer. We have demonstrated the potential application of PEGylated phospholipid membrane in imaging ellipsometry-based protein biosensor. Because of the strong resistance against non-specific adsorption of serum, antigens are immobilized onto the membrane surface through chemical activation and further bind their antibodies without using blocking agent. Taking advantage of the multiple and parallel reaction capabilities of microfluidic reactor system, we have assayed the binding by varying both the density of antigen on the membrane surface and the concentration of antibody in solution.

► Air stable phospholipid membrane microarray is formed on silicon surface. ► Polymer sandwiched membrane shows strong nonspecific adsorption resistance against serum. ► Preliminary application in the immunoassay is shown by imaging ellipsometry-based biosensor.