title: A sandwich HIV p24 amperometric immunosensor based on a direct gold electroplating-modified electrode.
abstract: Acquired immune deficiency syndrome (AIDS) is a severe communicable immune deficiency disease caused by the human immune deficiency virus (HIV). The analysis laboratory diagnosis of HIV infection is a crucial aspect of controlling AIDS. The p24 antigen, the HIV-1 capsid protein, is of considerable diagnostic interest because it is detectable several days earlier than host-generated HIV antibodies following HIV exposure. We present herein a new sandwich HIV p24 immunosensor based on directly electroplating an electrode surface with gold nanoparticles using chronoamperometry, which greatly increased the conductivity and reversibility of the electrode. Under optimum conditions, the electrochemical signal showed a linear relationship with the concentration of p24, ranging from 0.01 ng/mL to 100 ng/mL (R > 0.99), and the detection limit was 0.008 ng/mL. Compared with ELISA, this method increased the sensitivity by more than two orders of magnitude (the sensitivity of ELISA for p24 is about 1 ng/mL). This immunosensor may be broadly applied to clinical samples, being distinguished by its ease of use, mild reaction conditions, guaranteed reproducibility, and good anti-interference ability.
authors.affiliation: Clinical Laboratory Center, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zheng
authors.forename: Liyong
authors.initials: L
authors.lastname: Jia
authors.forename: Bo
authors.initials: B
authors.lastname: Li
authors.forename: Bo
authors.initials: B
authors.lastname: Situ
authors.forename: Qinlan
authors.initials: Q
authors.lastname: Liu
authors.forename: Qian
authors.initials: Q
authors.lastname: Wang
authors.forename: Ning
authors.initials: N
authors.lastname: Gan
mesh_terms: D055910:Antibodies, Immobilized; D015374:Biosensing Techniques / Q000379:methods*; D004566:Electrodes; D004595:Electroplating; D006046:Gold; D015483:HIV Antibodies; D016655:HIV Core Protein p24 / Q000276:immunology*; D015658:HIV Infections / Q000175:diagnosis*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013696:Temperature; D013997:Time Factors
chemical_list: D055910:Antibodies, Immobilized; D015483:HIV Antibodies; D016655:HIV Core Protein p24; D006046:Gold