RESUMEN
A potential binding assay based on binding-driven micromechanical motion is described. Acetylcholine binding protein (AChBP) was used to modify a microcantilever. The modified microcantilever was found to bend on application of the naturally occurring agonist (acetylcholine) or the antagonist (nicotine and d-tubocurarine). Control experiments show that microcantilevers modified without AChBP do not respond to acetylcholine, nicotine, and d-tubocurarine. K(d) values obtained for acetylcholine, nicotine, and d-tubocurarine are similar to those obtained from radio-ligand binding assays. These results suggest that the microcantilever system has potential for use in label free, drug screening applications.
Asunto(s)
Acetilcolina/análisis , Técnicas Biosensibles/métodos , Descubrimiento de Drogas/métodos , Sistemas Microelectromecánicos/métodos , Acetilcolina/agonistas , Acetilcolina/metabolismo , Técnicas Biosensibles/instrumentación , Ligandos , Sistemas Microelectromecánicos/instrumentación , Nicotina/análisis , Nicotina/metabolismo , Antagonistas Nicotínicos/análisis , Antagonistas Nicotínicos/metabolismo , Unión Proteica , Ensayo de Unión Radioligante/métodos , Coloración y Etiquetado , Tubocurarina/análisis , Tubocurarina/metabolismoRESUMEN
In the last fifteen years, microcantilevers (MCLs) have been emerging as a sensitive tool for the detection of chemicals and bioorganisms. Because of their small size, lightweight, and high surface-to-volume ratio, MCL-based sensors improve our capability to detect and identify biological agents by orders of magnitude. A biosensor is a device for the detection of an analyte that combines a biological component with a physicochemical detector component. The MCL biosensors have recently been reviewed in several papers. All of these papers were organized based on the sensing biological elements (antibody, enzyme, proteins, etc.) for recognition of analytes. In this review, we intend to summarize the microcantilever biosensors in a format of each specific chemical and bioorganism species to make information on individual biosensors easily accessible. We did this to aid researchers to locate relevant references.
Asunto(s)
Técnicas Biosensibles/métodos , Compuestos Orgánicos/química , Bacterias/aislamiento & purificación , Hongos/aislamiento & purificación , Metales Pesados/química , Monosacáridos/química , Proteínas/química , Virus/aislamiento & purificaciónRESUMEN
Microcantilevers (MCLs) hold a position as a cost-effective and highly sensitive sensor platform for medical diagnostics, environmental analysis and fast throughput analysis. MCLs are unique in that adsorption of analytes on the microcantilever (MCL) surface changes the surface characteristics of the MCL and results in bending of the MCL. Surface stress due to conformation change of proteins and other polymers has been a recent focus of MCL research. Since conformational changes in proteins can be produced through binding of anylates at specific receptor sites, MCLs that respond to conformational change induced surface stress are promising as transducers of chemical information and are ideal for developing microcantilever-based biosensors. The MCL can also potentially be used to investigate conformational change of proteins induced by non-binding events such as post-translational modification and changes in temperature or pH. This review will provide an overview of MCL biosensors based on conformational change of proteins bound to the MCL surface. The models include conformational change of proteins, proteins on membranes, enzymes, DNA and other polymers.
Asunto(s)
Técnicas Biosensibles , Proteínas/análisis , Adsorción , Animales , Humanos , Microquímica/métodos , Nanotecnología , Conformación Proteica , Propiedades de SuperficieRESUMEN
We have investigated the sensing performance of protein-based microcantilever biosensors prepared from multiple surface conjugation chemistries. The 11-mercaptoundecanoic acid monolayers were prepared according to both traditional and modified processes. In three protein-based biosensors, the modified process improved microcantilever sensing performance by increasing the bending amplitude, a critical step toward developing a cost-effective microcantilever-based sensor platform for medical diagnostics and environmental and drug screening applications. Scanning electron microscopy (SEM) images demonstrated that proteins immobilized on the microcantilever surface using the modified chemistry approach formed a compact layer.