RESUMEN
The number of Adenovirus (Ad) infections detected in immunocompromised people has increased due to the number of patients receiving transplants, as well as the HIV pandemic. Ads cause life-threatening diseases specific to the infected organs of immunocompromised hosts, with discontinuation of immunosuppressive agents necessary to prevent morbidity. The methodology in this paper has been employed to develop a novel impedimetric based assay platform to detect and quantify human Ads, which is comparable in performance to current methods, such as ELISA and PCR, but is also less expensive and faster. Novel immunosensors have been fabricated using polyclonal antibodies raised against a human Ad (Ad5) capsid protein, which were selectively cleaved into antibody fragments by 2-mercaptoethylamine. The fragments were immobilized onto a functionalized conducting copolymer matrix comprising polyaniline and 2-aminobenzylamine. Fully fabricated sensors were incubated with two immunologically distinct serotypes of Ad, Ad5 and Ad3, with between 10 and 10(12)virus particles/mL prior to sensor interrogation. Electrochemical impedance spectroscopy was used to measure the charge transfer resistance of the sensors over a range of frequencies from 25 kHz to 0.1 Hz. Our data demonstrate that the immunosensors specifically detect, and differentiate between, closely related human Ad serotypes with a limit of detection of 10(3)virus particles/mL. In addition, atomic force microscopy was applied to study the sensor surface nanostructure. Future work looks to test virus containing clinical samples but this could be a viable and valuable alternative for point-of-care virus detection and quantification.
Asunto(s)
Infecciones por Adenoviridae/diagnóstico , Adenoviridae/inmunología , Adenoviridae/aislamiento & purificación , Anticuerpos Inmovilizados/inmunología , Técnicas Biosensibles/métodos , Espectroscopía Dieléctrica/métodos , Infecciones por Adenoviridae/inmunología , Compuestos de Anilina/química , Anticuerpos Inmovilizados/química , Bencilaminas/química , Proteínas de la Cápside/inmunología , Humanos , Inmunoensayo/métodos , Límite de Detección , Propiedades de SuperficieRESUMEN
Rapid identification of viruses has important implications for medical healthcare. Current methods for identification and quantification of particular virus are time consuming and often expensive. Therefore, demand for sensitive and accurate viral biosensors with rapid detection systems is increasing. A hand held biosensing device would give fast, reliable results for identifying and quantitating the number of virus particles in a sample. Techniques currently being applied to achieve this aim include electrochemical biosensors, based on amperometric, potentiometric and impedance measurement, optical biosensors using surface plasmon resonance (SPR), optical fibers and piezoelectric biosensors based on microcantilevers. Future research also looks to the use of nanoparticles and novel nanomaterials as alternate recognition surfaces for use in a variety of sensor formats.