Exosomes are cell-derived nanovesicles that have recently gained popularity as potential biomarkers in liquid biopsies due to the large amounts of molecular cargo they carry,such as nucleic acids and proteins.However,...Exosomes are cell-derived nanovesicles that have recently gained popularity as potential biomarkers in liquid biopsies due to the large amounts of molecular cargo they carry,such as nucleic acids and proteins.However,most existing exosome-based analytical sensing methods struggle to achieve high sensitivity and high selectivity simultaneously.In this work,we present an electrochemical micro-aptasensor for the highly sensitive detection of exosomes by integrating a micropatterned electrochemical aptasensor and a hybridization chain reaction(HCR)signal amplification method.Specifically,exosomes are enriched on CD63 aptamer-functionalized electrodes and then recognized by HCR products with avidin-horseradish peroxidase(HRP)attached using EpCAM aptamers as bridges.Subsequently,the current signal that is generated through the enzyme reaction between the HRP enzyme and 3,3,,5/5,-tetramethylbenzidine(TMB)/H_(2)0_(2) directly correlates to the amount of bound HRP on the HCR products and thus to the number of target exosomes.By introducing anti-EpCAM aptamers,micro-aptasensors can detect cancerous exosomes with high specificity.Due to the micropatterned electrodes and HCR dual-amplification strategy,the micro-aptasensors achieve a linear detection response for a wide range of exosome concentrations from 2.5×10^(3) to 1×10^(7) exosomes/mL,with a detection limit of 5×10^(2) exosomes/mL.Moreover,our method successfully detects lung cancer exosomes in serum samples of early-stage and late-stage lung cancer patients,showcasing the great potential for early cancer diagnosis.展开更多
基金support of National Institutes of Health(NIH)grants U18TR003778 and R01GM135486Wenfen Zhang acknowledges the support of the National Natural Science Foundation of China(22004109)the China Scholarship Council.Guozhen Liu acknowledges the support of the Chinese University of Hong Kong,Shenzhen providing the University Development fund and Presidential Fellow fund.Joseph Rich acknowledges that this material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No.1644868.
文摘Exosomes are cell-derived nanovesicles that have recently gained popularity as potential biomarkers in liquid biopsies due to the large amounts of molecular cargo they carry,such as nucleic acids and proteins.However,most existing exosome-based analytical sensing methods struggle to achieve high sensitivity and high selectivity simultaneously.In this work,we present an electrochemical micro-aptasensor for the highly sensitive detection of exosomes by integrating a micropatterned electrochemical aptasensor and a hybridization chain reaction(HCR)signal amplification method.Specifically,exosomes are enriched on CD63 aptamer-functionalized electrodes and then recognized by HCR products with avidin-horseradish peroxidase(HRP)attached using EpCAM aptamers as bridges.Subsequently,the current signal that is generated through the enzyme reaction between the HRP enzyme and 3,3,,5/5,-tetramethylbenzidine(TMB)/H_(2)0_(2) directly correlates to the amount of bound HRP on the HCR products and thus to the number of target exosomes.By introducing anti-EpCAM aptamers,micro-aptasensors can detect cancerous exosomes with high specificity.Due to the micropatterned electrodes and HCR dual-amplification strategy,the micro-aptasensors achieve a linear detection response for a wide range of exosome concentrations from 2.5×10^(3) to 1×10^(7) exosomes/mL,with a detection limit of 5×10^(2) exosomes/mL.Moreover,our method successfully detects lung cancer exosomes in serum samples of early-stage and late-stage lung cancer patients,showcasing the great potential for early cancer diagnosis.
