Detailed evaluation of protein adsorption on alumina surface through surface plasmon resonance phenomenon

• Published in: Applied surface science 2012-10, Vol.258 (24), p.9526-9530
• Main Authors: Akasaka, Hiroki, Konishi, Miyuki, Gawazawa, Naoki, Ohshio, Shigeo, Toda, Ikumi, Saitoh, Hidetoshi
• Format: Article
• Language: English
• Subjects: Adsorption; Alumina; Aluminum oxide; Angle of reflection; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Devices; Etching; Exact sciences and technology; Human serum albumin; Multilayer SPR device; Phosphors; Physics; Plasmons; Protein adsorption; Surface chemistry; Surface plasmon resonance
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2012.05.020

► Alumina films were studied in terms of their initial protein adsorption through the SPR to investigate the adsorption of HSA. ► Na2HPO4·12H2O, NaH2PO4·2H2O and deionized water were mixed to coordinate the PB. ► The observed SPR angle behavior indicated that HSA was immediately adsorbed on alumina films. ► The adsorbed HSA was desorbed by the etching of the alumina layer. ► Thus, HSA cannot remain adsorbed on an alumina layer for a long time. To investigate the adsorption of human serum albumin (HSA) on alumina, alumina films were studied in terms of their initial protein adsorption through the surface plasmon resonance (SPR) phenomenon using a multilayer device consisting of an alumina layer on Au. HSA in a phosphor buffer (PB) was used as a protein. Na2HPO4·12H2O, NaH2PO4·2H2O, and deionized water were mixed to coordinate the PB. From the attenuation of reflected light, the SPR angle was determined as the angle with minimum reflection intensity. The observed behavior of the SPR angle indicated that HSA cannot remain adsorbed on alumina for a long time. To understand this phenomenon, the etching rates of PB solutions were estimated, and were −3.44, −2.64, and −0.41nm/h for 0.5, 0.3, 0.1M solutions, respectively. Upon evaluating the adsorption of HSA, the observed SPR angle behavior indicated that HSA was immediately adsorbed on alumina films. After that, the adsorbed HSA was desorbed by the etching of the alumina layer. Hence, these results also indicated that HSA cannot remain adsorbed on an alumina layer for a long time.