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Updated: Mar 10, 2026
Combination of Adhesive-tape-based Sampling and Fluorescence in situ Hybridization for Rapid Detection of Salmonella on Fresh Produce
Published on: October 18, 2010
QCM-based aptamer selection and detection of Salmonella typhimurium
Lijun Wang1, Ronghui Wang2, Fang Chen3
1State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China; Department of Biological & Agricultural Engineering, University of Arkansas, Fayetteville, AR 72701, USA.
Abstract:
In this study, quartz crystal microbalance (QCM) was used to select aptamers against Salmonella typhimurium. To increase the success rate of Systematic Evolution of Ligands Exponential Enrichment (SELEX), the affinity of DNA pool in each round was simultaneously tracked using QCM in order to avoid the loss of high-quality aptamers. When the frequency change reached a maximum value after several rounds of selection and counter-selection, the candidate pool was cloned and sequenced. Out of three aptamer candidates, aptamer B5 showed high specificity and binding affinity with dissociation constant (Kd value) of 58.5nM, and was chosen for further studies. Subsequently, a QCM-based aptasensor was developed to detect S. typhimurium. This aptasensor was able to detect 103CFU/mL of S. typhimurium with less than 1h. This study demonstrated QCM-based selection could be more effective selection of aptamers and QCM-based aptasensor could be more sensitive in detecting S. typhimurium.
