Gold nanoparticles conjugates-amplified aptamer immunosensing screen-printed carbon electrode strips for thrombin detection.

Thrombin plays the role in cardiovascular diseases and regulates many processes in inflammation and could be a feature of many pathological conditions, including the thromboembolic disease, cancer and neurodegenerative diseases. An ultrasensitive and amplified electrochemical sandwich assay using screen-printed carbon electrode (SPCE) strips for thrombin detection was established in this study. The conductivity and sensing performance of the carbon electrodes were enhanced by using gold nanoparticles (AuNPs). The aptamer addressed on the strips was used as a primary probe to capture thrombin in the detected samples. An amplifier was invented for recognizing thrombin captured on the SPCE, which is the multiple molecules of anti-thrombin antibody (Ab) and horseradish peroxidase (HRP) co-modified AuNPs (AuNPs/Ab-HRP). Hydrogen peroxide was used as the substrate for HRP and then the response current (RC) could be detected. The optimization of these AuNPs conjugates-amplified aptamer immunosensing SPCE strips was conducted for thrombin detection. The detection sensitivity showed a linear relation between RC and thrombin concentration in the range of 10 pM-100 nM, and limit of detection (LOD) was 1.5 pM. The fabricated AuNPs/Ab-HRP-amplified aptamer immunosensing SPCE strips were further used to detect thrombin in human serum with a linear range of 100 pM-100 nM. This study provided the promising SPCE strips with highly sensitive and rapid detection for thrombin by the electrochemical aptasensor combined with AuNPs conjugates for amplifying the detection signal.

Yeh FY ，Liu TY ，Tseng IH ，Yang CW ，Lu LC ，Lin CS ... -  《-》

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 ... -  《-》

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 ... -  《-》

Disposable amperometric immunosensing strips fabricated by Au nanoparticles-modified screen-printed carbon electrodes for the detection of foodborne pathogen Escherichia coli O157:H7.

Lin YH ，Chen SH ，Chuang YC ，Lu YC ，Shen TY ，Chang CA ，Lin CS ... -  《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 ... -  《-》