which is mixture of glycine and lipase from pseudomonas cepacia was first purified by a sephadex g 25 fine gel column see k tanaka et al langmuir 1999 the percent yield for this purification process was typically 40 50 this is in agreement with the fact that the unpurified lipase mixture contains approximately 50 glycine by weight then the substrate was soaked in the lipase solution with the concentration of 337 mg l after soaking for 4 hours the substrate was taken out and rinsed in the water for 5 minutes polarization modulation fourier transform infrared reflection adsorption pm ft irras spectra of 1000 scans at 2 cm 1 resolution were obtained with a mattson rs 1 spectrometer and a narrow band hgcdte detector the thickness of phospholipid monolayer on gold substrate and absorbed protein were determined with the optical technique of surface plasmon resonance the surface morphology was analyzed by atomic force microscopy molecules of thiol terminated phospholipid were chemisorbed onto a fresh polycrystalline gold surface by immersion for approximately 24 hours in a 1 mm solution in mixed methylene and methanol with the ratio of two to one immersion of gold substrate for a longer period such as 3 and 4 days no spectroscopic differences were observed in order to confirm that the phospholipid were indeed chemisorbed on gold surface via the reaction between gold and thiol group of phospholipid spectroscopy was employed as primary method for monitoring the chemical structure of adsorbed monolayer after thoroughly rinsing with mixed solvent of methylene and methanol the measurement was made we confirmed that the aminoethanthiol molecule had attached to the end of acyl chain.