Ag-coated submicron particles of polystyrene formed by dewetting process and their application in multi-functional biosensor-chips

The formation of submicron polystyrene (PS) particles based on dewetting process during spin-coating was investigated. The surface morphologies on glass substrates were analyzed. The formation of particles was achieved using PS with relatively high molecular weight (Mw ≥ 3250). In addition, it was observed that the particle formation proceeded through sequential morphological changes in the order of initial wet thin film, secondary spinodal-decomposed structures, and eventual dewetted particles. One of the fabricated samples exhibited obvious optical resonance in the visible region based on the relationship between particle dimeters and optical wavelengths in the visible region. The optical resonance strongly depended on the ambient refractive index, which can be used for optical sensor-chips. Finally, a multi-functional biosensor-chip was demonstrated to detect glucose in water solutions.