In partnership with the Air Force Office of Scientific Research (AFOSR), the National Science Foundation's (NSF) Emerging Frontiers and Multidisciplinary Activities (EFMA) office of the Directorate for Engineering (ENG) launched an Emerging Frontiers in Research and Innovation (EFRI) topic for the fiscal years FY22 and FY23 entitled "Brain-inspired Dynamics for Engineering Energy-Efficient Circuits and Artificial Intelligence" (BRAID) [...
View Article and Find Full Text PDFThe emergence of the COVID-19 pandemic has starkly exposed our significantly limited ability to promptly identify and respond to emergent biological threats. Consequently, there is an urgent need to advance biotechnological methods for addressing both known and unforeseen biological hazards. Recently, the CRISPR/Cas system has revolutionized genetic engineering, enabling precise and efficient synthetic biology applications.
View Article and Find Full Text PDFUnderstanding the chemical composition and morphology of interfaces plays a vital role in the development of sensors, drug delivery systems, coatings for biomedical implants, and so forth. In many cases, the interface characterization can be performed by a combination of electrochemical and one of the optical techniques. In this study, we further enhanced capabilities in probing interfaces by combining electrochemical characterization with multiple optical techniques, that is, surface plasmon resonance (SPR) and fluorescence spectroscopy.
View Article and Find Full Text PDFOrganophosphate compounds are heavily used in agriculture and military activities, while non-organophosphate pesticides are mostly used in agriculture and home defense. Discriminative detection of such toxic compounds is very challenging and requires sophisticated and bulky instrumentation. Meanwhile, multi-enzyme biosensors may offer an effective solution to the problem and may become a versatile analytical tool for discriminative detection of different neurotoxins.
View Article and Find Full Text PDFBiosensors are of great significance because of their capability to resolve a potentially large number of analytical problems and challenges in very diverse areas such as defense, homeland security, agriculture and food safety, environmental monitoring, medicine, pharmacology, industry, etc. The expanding role of biosensing in society and a real-world environment has led to an exponential growth of the R&D efforts around the world. The world market for biosensor devices, according to Global Industry Analysts, Inc.
View Article and Find Full Text PDFCampylobacter spp. are an important cause of acute bacterial diseases in humans worldwide. Many bacterial species in the Campylobacter genus are considered harmful and may cause several infectious diseases.
View Article and Find Full Text PDFWe develop a framework for optimizing a novel approach to extending the linear range of bioanalytical systems and biosensors by utilizing two enzymes with different kinetic responses to the input chemical as their substrate. Data for the flow injection amperometric system devised for detection of lysine based on the function of L-lysine-alpha-oxidase and lysine-2-monooxygenase are analyzed. Lysine is a homotropic substrate for the latter enzyme.
View Article and Find Full Text PDFThe applications of biosensors range from environmental testing and biowarfare agent detection to clinical testing and cell analysis. In recent years, biosensors have become increasingly prevalent in clinical testing and point-of-care testing. This is driven in part by the desire to decrease the cost of health care, to shift some of the analytical tests from centralized facilities to "frontline" physicians and nurses, and to obtain more precise information more quickly about the health status of a patient.
View Article and Find Full Text PDFCurrent bacterial detection methods require the collection of samples followed by preparation and analysis in the laboratory, both time and labour consuming steps. More importantly, because of cost, only a limited number of samples can be taken and analyzed. This paper presents the results of an investigation to directly detect Salmonella typhimurium on fresh tomato surfaces using phage-based magnetoelastic (ME) biosensors.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
October 2010
In this study, a novel system for the detection and quantification of organofluorophosphonates (OFP) has been developed by using an optical sensing polymeric membrane to detect the fluoride ions produced upon OFP hydrolysis. Diisopropyl fluorophosphate (DFP), a structural analogue of type G chemical warfare agents such as Sarin (GB) and Soman (GD), is used as the surrogate target analyte. An optical sensing fluoride ion selective polymeric film was formulated from plasticized PVC containing aluminum(III) octaethyl porphyrin and ETH 7075 chromoionophore (Al[OEP]-ETH 7075).
View Article and Find Full Text PDFThis paper describes a biomaterial microfabrication approach for interfacing functional biomolecules (enzymes) with electrode arrays. Poly (ethylene glycol) (PEG) hydrogel photopatterning was employed to integrate gold electrode arrays with the enzymes glucose oxidase (GOX) and lactate oxidase (LOX). In this process, PEG diacrylate (DA)-based prepolymer containing enzyme molecules as well as redox species (vinylferrocene) was spin-coated, registered, and UV cross-linked on top of an array of gold electrodes.
View Article and Find Full Text PDFIn this paper we demonstrate that SWNTs and a covalent immobilization strategy enable very sensitive sensors with excellent long term stability. Organophosphorus hydrolase (OPH) functionalized single and multi-walled carbon nanotube (CNT) conjugates were exploited for direct amperometric detection of paraoxon, a model organophosphate. The catalytic hydrolysis of paraoxon produces equimoles of p-nitrophenol; oxidation was monitored amperometrically in real time under flow-injection (FIA) mode.
View Article and Find Full Text PDFElectrode-immobilized glucose-6-phosphate dehydrogenase is used to catalyze an enzymatic reaction which carries out the AND logic gate. This logic function is considered here in the context of biocatalytic processes utilized for the biocomputing applications for "digital" (threshold) sensing/actuation. We outline the response functions desirable for such applications and report the first experimental realization of a sigmoid-shape response in one of the inputs.
View Article and Find Full Text PDFProtein immobilization on solid interfaces is a crucial aspect of their successful application in technologies such as biosensing, purification, separation, decontamination, etc. Although immobilization can improve the long-term and operational stability of proteins, this is often at the cost of significant losses in the catalytic activity of the tethered enzyme. Covalent attachment methods take advantage of reactive groups on the amino acid side chains.
View Article and Find Full Text PDFWe demonstrate a rapid method for enzyme immobilization directly on a waveguide surface by encapsulation in a silica matrix. Organophosphate hydrolase (OPH), an enzyme that catalytically hydrolyzes organophosphates, was used as a model enzyme to demonstrate the utility of lysozyme-mediated silica formation for enzyme stabilization. Silica morphology and the efficiency of OPH encapsulation were directly influenced by the precursor choice used in silica formation.
View Article and Find Full Text PDFLarge scale biomimetic single-walled carbon nanotube (SWNT) coatings with significant antimicrobial activity, high Young's Modulus, and controlled morphology were fabricated using layer-by-layer assembly. Thickness was controlled within 1.6 nm and SWNT orientation was controlled using a directed air stream.
View Article and Find Full Text PDFA novel detection method for organophosphate neurotoxins has been described, based on the fluorescence quenching of a Coumarin derivative. These dyes are similar in structure to some organophosphates (OPs), and they fluoresce in the blue-green region of the spectra. This methodology has been utilized for the detection of organophosphates whose hydrolysis product is p-nitrophenol by using an enzyme, organophosphorus hydrolase (OPH).
View Article and Find Full Text PDFDevelopment of real-time sensor based on the target-specific probe that make possible sensitive, rapid and selective detection and monitoring of the particular antigen molecules could be of substantial importance to the many applications. Because of its high specificity to the target molecules, excellent temperature stability, and easy production, bacterial phage might serve as a powerful biorecognition probe in biosensor applications. Here, we report extremely sensitive and specific label-free direct detection of model antigen, beta-galactosidase (beta-gal), based on surface plasmon resonance (SPR) spectroscopy.
View Article and Find Full Text PDFThe purpose of this study was to develop a biosensor based on surface plasmon resonance (SPR) for the rapid identification of C. jejuni in broiler samples. We examined the specificity and sensitivity of commercial antibodies against C.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
July 2007