Nonspecific-adsorption behavior of polyethylenglycol and bovine serum albumin studied by 55-MHz wireless-electrodeless quartz crystal microbalance

作者：Ogi Hirotsugu^*; Fukunishi Yuji; Nagai Hironao; Okamoto Ken; Hirao Masahiko; Nishiyama Masayoshi

来源：Biosensors and Bioelectronics, 2009, 24(10): 3148-3152.

DOI：10.1016/j.bios.2009.03.035

• Nonspecific adsorption
• Affinity
• Electrodeless
• QCM

The nonspecific binding ability of polyethylenglycol (PEG) and bovine serum albumin (BSA) on modified and unmodified surfaces is quantitatively studied by a wireless-electrodeless quartz crystal microbalance (WE-QCM). PEG and BSA are important blocking materials in biosensors. but their affinities for proteins and uncoated substrates have not been known quantitatively. The WE-QCM allows quantitative analysis of the adsorption behavior of proteins on the electrodeless surfaces. Affinities of PEG, BSA, human immunoglobulin G (hlgG), and Staphylococcus protein A (SPA) for alpha-SiO(2)(quartz), Au thin film, PEG, and BSA are systematically studied by the homebuilt flow-injection system. PEG shows low affinities for the SiO(2) surface (K(A) = 4.2 x 10(4) M(-1)) and the Au surface (K(A) = 6.6 x 10(4) M(-1)). but BSA shows higher affinity for the SiO(2) surface (K(A) = 1.4 x 10(6) M(-1)). Both PEG and BSA show low affinities for hIgG (K(A)similar to 1.5 x 10(5) M(-1)). However, the number of binding sites of PEG to hIgG is significantly larger than that of BSA, indicating that blocking for hIgG is favorably achieved by BSA, rather than PEG.

• 出版日期2009-6-15