Enhancing Biosensor Performance with Omniphobic Lubricant-Infused Coatings

Abstract

Point-of-care testing brings diagnosis and treatment monitoring to the site of the patient. It heavily relies on biosensors, which leverage the interactions between a target biomarker and a bioreceptor, to deliver fast and accurate results. However, non-specific binding of molecules and microorganisms on the biointerface can interfere with biomarker-bioreceptor interactions and diminish a biosensor’s sensitivity, specificity, and stability. In turn, this can lead to false diagnoses and ineffective treatments. Omniphobic-lubricant infused (OLI) coatings exhibit slippery, self-cleaning characteristics that repel untargeted molecules and microorganisms to augment the biosensor’s performance. In this work, we investigate the proficiency of OLI coatings in two specific applications: dissolved oxygen sensing and DNA biosensing. First, in water quality monitoring, an OLI coating is applied to the selectively permeable membranes of a dissolved oxygen sensor. Over a three-week incubation period in an environment with accelerated bacterial growth, the coated membranes exhibit a 160% higher reproducibility (10% deviation in sensitivity) and lower biofilm formation (96° static contact angle) in comparison to unmodified membranes (26%, 32°). The second application is in DNA biosensing, where a novel OLI coating uses carbon dioxide plasma activation to embed oligonucleotide probes. It demonstrates an optimized balance of slippery repellency (76° static contact angle, 10° sliding angle) and biosensing functionality, 19% longer clotting times than conventional blocking conditions, and equal sensitivity to PLL-PEG when capturing target DNA in whole blood. Going forward, our research will continue to expand the use of OLI coatings in biosensing applications, particularly exploiting its antibiofouling and anticoagulative capabilities.