Sensing levofloxacin with an RNA aptamer as bioreceptor

The emergence and spread of antibiotic resistance among microbial pathogens represents a sig-nificant, global, and growing threat to public health. The evolution of new antibiotic resistances is caused by various factors, including the overuse and misuse of antibiotics in human medicine, animal husbandry, and agriculture, as well as environmental contamination. Consequently, there is a pressing need for effective strategies to combat this crisis, with environmental testing for an-tibiotic contamination playing an increasingly crucial role. RNA aptamers have shown great promise in the detection of small molecules, such as antibiotics. In this study a rapid and easy method for the development of aptamer based lateral flow assays is demonstrated. As a proof of concept, the fluoroquinolone-antibiotic levofloxacin was chosen. Levofloxacin is used in human and veterinary medicine and was detected in waste- and river water. It can severely affect aquat-ic microbial life and may promote antibiotic resistance in aquatic bacteria. An aptamer against levofloxacin was selected using RNA Capture-SELEX, a method that offers unique benefits for the selection of biosensing aptamers. The aptamer was thoroughly characterized and used to develop an easy-to-use lateral flow assay.