Ultrasensitive electrochemical aptasensor for thrombin based on the amplification of aptamer-AuNPs-HRP conjugates.

Successful development of an ultrasensitive and highly specific electrochemical aptasensor for thrombin based on amplification of aptamer-gold nanoparticles-horseradish peroxidase (aptamer-AuNPs-HRP) conjugates was reported. In this electrochemical protocol, aptamer1 (Apt1) was immobilized on core/shell Fe(3)O(4)/Au magnetic nanoparticles (AuMNPs) and served as capture probe. Aptamer2 (Apt2) was dual labeled with AuNPs and HRP and used as detection probe. In the presence of thrombin, the sandwich format of AuMNPs-Apt1/thrombin/Apt2-AuNPs-HRP was fabricated. Remarkable signal amplification was realized by taking the advantage of AuNPs and catalytic reactions of HRP. Other proteins, such as human serum albumin, lysozyme, fibrinogen, and IgG did not show significant interference with the assay for thrombin. Linear response to thrombin concentration in the range of 0.1-60 pM and lower detection limit down to 30 fM (S/N=3) was obtained with the proposed method. This electrochemical aptasensor is simple, rapid (the whole detection period for a thrombin sample is less than 35 min), sensitive and highly specific, it shows promising potential in protein detection and disease diagnosis.

Zhao J ，Zhang Y ，Li H ，Wen Y ，Fan X ，Lin F ，Tan L ，Yao S ... -  《-》

Dual amplification strategy of highly sensitive thrombin amperometric aptasensor based on chitosan-Au nanocomposites.

Zhao J ，Lin F ，Yi Y ，Huang Y ，Li H ，Zhang Y ，Yao S ... -  《-》

Apoferritin protein nanoparticles dually labeled with aptamer and horseradish peroxidase as a sensing probe for thrombin detection.

A novel and ultrasensitive sandwich-type electrochemical aptasensor has been developed for the detection of thrombin, based on dual signal-amplification using HRP and apoferritin. Core/shell Fe(3)O(4)/Au magnetic nanoparticles (AuMNPs) loading aptamer1 (Apt1) was used as recognition elements, and apoferritin dually labeled with Aptamer2 (Apt2) and HRP was used as a detection probe. Sandwich-type complex, Apt1/thrombin/Apt2-apoferritin NPs-HRP was formed by the affinity reactions between AuMNPs-Apt1, thrombin, and Apt2-apoferritin-HRP. The complex was anchored on a screen-printed carbon electrode (SPCE). Differential pulse voltammetry (DPV) was used to monitor the electrode response. The proposed aptasensor yielded a linear current response to thrombin concentrations over a broad range of 0.5-100 pM with a detection limit of 0.07 pM (S/N=3). The detection signal was amplified by using apoferritin and HRP. This nanoparticle-based aptasensor offers a new method for rapid, sensitive, selective, and inexpensive quantification of thrombin, and offers a promising potential in protein detection and disease diagnosis.

Zhao J ，Liu M ，Zhang Y ，Li H ，Lin Y ，Yao S ... -  《-》

Amplified electrochemical aptasensor taking AuNPs based sandwich sensing platform as a model.

Li B ，Wang Y ，Wei H ，Dong S ... -  《BIOSENSORS & BIOELECTRONICS》

Highly sensitive electrochemical label-free aptasensor based on dual electrocatalytic amplification of Pt-AuNPs and HRP.

Bai L ，Yuan R ，Chai Y ，Yuan Y ，Mao L ，Zhuo Y ... -  《-》