title: An aptamer-based biosensing platform for highly sensitive detection of platelet-derived growth factor via enzyme-mediated direct electrochemistry.
abstract: In this work, a new label-free electrochemical aptamer-based sensor (aptasensor) was constructed for detection of platelet-derived growth factor (PDGF) based on the direct electrochemistry of glucose oxidase (GOD). For this proposed aptasensor, poly(diallyldimethylammonium chloride) (PDDA)-protected graphene-gold nanoparticles (P-Gra-GNPs) composite was firstly coated on electrode surface to form the interface with biocompatibility and huge surface area for the adsorption of GOD layer. Subsequently, gold nanoclusters (GNCs) were deposited on the surface of GOD to capture PDGF binding aptamer (PBA). Finally, GOD as a blocking reagent was employed to block the remaining active sites of the GNCs and avoid the nonspecific adsorption. With the direct electron transfer of double layer GOD membranes, the aptasensor showed excellent electrochemical response and the peak current decreased linearly with increasing logarithm of PDGF concentration from 0.005 nM to 60 nM with a relatively low limit of detection of 1.7 pM. The proposed aptasensor exhibited high specificity, good reproducibility and long-term stability, which provided a new promising technique for aptamer-based protein detection.
authors.affiliation: Laboratory of the Clinical Experimental Base of Biosensor and Microarray, Center of Molecule and Gene Diagnosis, Southwest Hospital, Third Military Medical University, Chongqing 400042, PR China.
authors.forename: Kun
authors.initials: K
authors.lastname: Deng
authors.forename: Yang
authors.initials: Y
authors.lastname: Xiang
authors.forename: Liqun
authors.initials: L
authors.lastname: Zhang
authors.forename: Qinghai
authors.initials: Q
authors.lastname: Chen
authors.forename: Weiling
authors.initials: W
authors.lastname: Fu
mesh_terms: D000818:Animals; D052157:Aptamers, Nucleotide / Q000378:metabolism*; D015374:Biosensing Techniques / Q000295:instrumentation*; D004563:Electrochemistry / Q000295:instrumentation*; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000378:metabolism; D005949:Glucose Oxidase / Q000378:metabolism*; D006108:Graphite / Q000737:chemistry; D057230:Limit of Detection; D053758:Nanoparticles / Q000737:chemistry; D010982:Platelet-Derived Growth Factor / Q000032:analysis* / Q000378:metabolism
chemical_list: D052157:Aptamers, Nucleotide; D004800:Enzymes, Immobilized; D010982:Platelet-Derived Growth Factor; D006108:Graphite; D005949:Glucose Oxidase