The 18th Beijing Conference and Exhibition on Instrumental Analysis (BCEIA 2019) hosted by China Association for Instrumental Analysis (CAIA) was held at China National Convention Center on October 23-26, 2019. This exhibition adheres to the direction of “Analytical Science to Creates Future” and organizes academic conferences, special forums and instrument exhibitions around the theme of “Moving towards a green future”.

    Zengnan Wu, a PhD student in our group, won the poster award with the title of "Ultrasensitive Detection of Thrombin Using MALDI-TOF Mass Spectrometry". In this study, a DNA-mediated rolling circle amplification (RCA) strategy was established for ultrasensitive and selective detection of the biomarker by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Thrombin as a model target was sandwiched between aptamer-functionalized magnetic beads and gold-nanoparticles, followed by RCA progress and DNA probes assembly. The product was then purified and analyzed using MALDI-TOF MS. The strategy converts the analysis of trace thrombin to the detection of numerous DNA probes, achieving ultrasensitive detection. The method also enabled the detection of thrombin in complex biological environments to demonstrate its selectivity and feasibility in real samples. With high sensitivity and specificity, this signal amplifying strategy can be applied for detection of various low abundant biomolecules.