The cuvette was then filled with aqHAuCl4 and aqAgB and was then placed inside the spectroscopy holder. Absorption spectra within wavelength range 350 and 800 nm were recorded at 20 min for 7 hours (Fig. ). Fig. illustrates the absorbance spectra for the evolution of AgNPs. UV-vis spectroscopy revealed absorption peaks between 440 and 450 nm, demonstrating that AgNPs were formed in the process. Likewise, the absorption peak between 530 and 545 nm demonstrated the formation of AuNPs at the interface between PDMS72h and aqHAuCl4 (Figure ). While, so far, we have analyzed progress of an in-situ chemical reaction, we will now present results on that for physisorption of a protein on the channel surface. Because of its hydrophobic nature, large variety of molecules, e.g. proteins, adsorb on its surface and the activity of adsorbed protein molecules depends on rate of its adsorption on a surface, particularly the initial rate, as it determines the configuration of the adsorbed molecule . Hence there is significant interest in estimating the initial adsorption rate of a protein. Adsorption rate consists of two components, diffusion of molecules from the bulk to the surface of the solid and the intrinsic rate of their adsorption on the surface (rate of desorption of protein is generally insignificantly small). In our experiment, aqueous solution of Bovine Serum Albumin (aqBSA)