Use of wavelength modulation surface plasmon resonance biosensor to study interaction of β-CD with serum albumin

The wavelength modulation surface plasmon resonance (SPR) biosensor was designed based on fixing the incident angle of light and measuring the reflected intensities at the resonance wavelength simultaneously. The interaction between beta-CD and serum albumin (human serum albumin, bovine serum albumin) was studied with the wavelength modulation SPR sensor, and kinetic constants, thermodynamic constants, and binding percentages were obtained, respectively. In addition, regeneration of the SPR biosensor was also studied. This method provides detailed information on affinities of the beta-CD binding to serum albumin. The equilibrium constant of the reaction for the beta-CD and HSA was 7.79 mu mol/L, while that for the beta-CD and BSA was 51.00 mu mol/L. The binding percentages were 98.77% and 94.25% for beta-CD binding HSA and BSA, respectively. These results indicated that their affinities were very high for beta-CD towards HSA and BSA.