Amplified voltammetric detection of dopamine using ferrocene-capped gold nanoparticle/streptavidin conjugates.
Dopamine (DA) is one of the most important neurotransmitters present in brain tissues and body fluids of mammals. The change in the concentration levels has been associated with various diseases and disorders. Thus, sensitive and selective determination of DA is much preferred. In this work, sandwich-type electrochemical biosensor was developed, in which phenylboronic acid immobilized onto gold electrodes was used to capture DA. The anchored DA was then derivatized with biotin for the attachment of ferrocene-capped gold nanoparticle/streptavidin conjugates. The voltammetric responses were found to be proportional to the concentrations of DA ranging from 0.5 to 50 nM. A detection limit of 0.2 nM was achieved, which is 1~2 orders of magnitude lower than those achievable at various chemically modified electrodes. Analytical merits (e.g., dynamic range, reproducibility, detection level, selectivity and interference) were evaluated. The feasibility of the method for analysis of DA in artificial cerebrospinal fluid and dopamine hydrochloride injection has been demonstrated.
College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang, Henan 455000, People's Republic of China. liulin@aynu.edu.cn
Lin
L
Liu
Jimin
J
Du
Sujuan
S
Li
Baiqing
B
Yuan
Hongxing
H
Han
Min
M
Jing
Ning
N
Xia
D000669:Amplifiers, Electronic; D015374:Biosensing Techniques / Q000295:instrumentation*; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis; D003217:Conductometry / Q000295:instrumentation*; D004298:Dopamine / Q000032:analysis*; D004566:Electrodes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005296:Ferrous Compounds / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D000075163:Metallocenes; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019809:Streptavidin / Q000737:chemistry*
D020099:Coated Materials, Biocompatible; D005296:Ferrous Compounds; D000075163:Metallocenes; D006046:Gold; D019809:Streptavidin; C004998:ferrocene; D004298:Dopamine