Biomaterial Database

Resonance energy transfer nanobiosensors based on affinity binding between apo-enzyme and its substrate. 2004

Swetha Chinnayelka, and Michael J McShane

Institute for Micromanufacturing, Louisiana Tech University, Ruston 71272, USA.

Systems for glucose monitoring based on resonance energy transfer (RET) and competitive binding using Concanavalin A (Con A) are problematic as a result of problems of toxicity, aggregation, and irreversible binding. This paper presents an improved RET assay wherein Con A was replaced by apo-glucose oxidase (apo-GOx). The basic principle for transduction is identical to that used in assays based on Con A-dextran: a reduction in RET from fluorescein isothiocyanate (FITC) to tetramethyl rhodamine isothiocyanate (TRITC) occurs when FITC-dextran (donor) is displaced from TRITC-apo-GOx (acceptor) as a result of the competition of glucose. Fluorescence measurements confirm that the apo-GOx/dextran complexes are highly sensitive to glucose, measured as an increase in the donor peak relative to acceptor due to stepwise addition of glucose. The solution-phase assay showed strong signals and excellent repeatability, with a sensitivity of 0.0163 (ratio units)/mM over the range of 0-90 mM glucose. If properly encapsulated, these sensors can potentially be used for in vivo sensing without the concern of toxicity associated with Con A.

UI	MeSH Term	Description	Entries
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D004735	Energy Transfer	The transfer of energy of a given form among different scales of motion. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed). It includes the transfer of kinetic energy and the transfer of chemical energy. The transfer of chemical energy from one molecule to another depends on proximity of molecules so it is often used as in techniques to measure distance such as the use of FORSTER RESONANCE ENERGY TRANSFER.	Transfer, Energy
D013056	Spectrophotometry, Ultraviolet	Determination of the spectra of ultraviolet absorption by specific molecules in gases or liquids, for example Cl2, SO2, NO2, CS2, ozone, mercury vapor, and various unsaturated compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Ultraviolet Spectrophotometry
D013379	Substrate Specificity	A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.	Specificities, Substrate,Specificity, Substrate,Substrate Specificities
D015374	Biosensing Techniques	Any of a variety of procedures which use biomolecular probes to measure the presence or concentration of biological molecules, biological structures, microorganisms, etc., by translating a biochemical interaction at the probe surface into a quantifiable physical signal.	Bioprobes,Biosensors,Electrodes, Enzyme,Biosensing Technics,Bioprobe,Biosensing Technic,Biosensing Technique,Biosensor,Electrode, Enzyme,Enzyme Electrode,Enzyme Electrodes,Technic, Biosensing,Technics, Biosensing,Technique, Biosensing,Techniques, Biosensing
D049329	Nanostructures	Materials which have structured components with at least one dimension in the range of 1 to 100 nanometers. These include NANOCOMPOSITES; NANOPARTICLES; NANOTUBES; and NANOWIRES.	Nanomaterials,Nanostructured Materials,Material, Nanostructured,Materials, Nanostructured,Nanomaterial,Nanostructure,Nanostructured Material