title: Interface potential sensing from adsorption of human serum albumin (HSA) on carbon nanotube (CNT) monitored by zero current potentiometry for HSA determination.
abstract: In this work, the adsorption of human serum albumin (HSA) on the bare multiwall carbon nanotube (MWNT) was investigated by a new electrochemical method, termed as zero current potentiometry. For this, a MWNT strip was prepared by directly adhering MWNTs on the transparent adhesive tape surface. Moreover, when HSA adsorbed onto MWNT at the MWNT/solution interface, an interface potential Ψ yielded. The interface potential Ψ as the zero current potential Ezcp simply related to it was monitored by zero current potentiometry. The relationship between the zero current potential Ezcp, the HSA concentration and others was established in simple stoichiometric relation. Based on this, both the adsorption of HSA on MWNT and the HSA determination can be studied. For the HSA determination, the theoretic conclusion consisted with experimental results. The zero current potential Ezcp was proportional to the HSA concentration in the range of 2.8 × 10(-8) - 3.4 × 10(-7)M with the limit of detection 2 × 10(-8)M. The linear regression equation was Ezcp/V (vs, SCE) = (0.159 ± 0.01) + (0.358 ± 0.02) × 10(6)CHSA (µM). This determination was fast, high sensitive and good selective.
authors.affiliation: Institute of Analytical Science, Northwest University, Xi'an 710069, China.
authors.forename: Huan
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Gynecology and Obstetrics, Fourth Hospital of Xi'an City, Xi'an 710004, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Institute of Analytical Science, Northwest University, Xi'an 710069, China. Electronic address: songjunf@nwu.edu.cn.
authors.forename: Jun-Feng
authors.initials: JF
authors.lastname: Song
mesh_terms: D000327:Adsorption; D004867:Equipment Design; D006801:Humans; D057230:Limit of Detection; D037742:Nanotubes, Carbon / Q000737:chemistry*; D011199:Potentiometry / Q000295:instrumentation*; D012709:Serum Albumin / Q000032:analysis / Q000302:isolation & purification*
chemical_list: D037742:Nanotubes, Carbon; D012709:Serum Albumin
keywords: Human serum albumin (HSA); Interface; Interface potential; Multiwall carbon nanotube (MWNT); Zero current potential; Zero current potentiometry