Label-free chemiresistive immunosensors for viruses.
We report development, characterization, and testing of chemiresistive immunosensors based on single polypyrrole (Ppy) nanowire for highly sensitive, specific, label free, and direct detection of viruses. Bacteriophages T7 and MS2 were used as safe models for viruses for demonstration. Ppy nanowires were electrochemically polymerized into alumina template, and single nanowire based devices were assembled on a pair of gold electrodes by ac dielectrophoretic alignment and anchored using maskless electrodeposition. Anti-T7 or anti-MS2 antibodies were immobilized on single Ppy nanowire using EDC-NHS chemistry to fabricate nanobiosensor for the detection of corresponding bacteriophage. The biosensors showed excellent sensitivity with a lower detection limit of 10(-3) plaque forming unit (PFU) in 10 mM phosphate buffer, wide dynamic range and excellent selectivity. The immunosensors were successfully applied for the detection of phages in spiked untreated urban runoff water samples. The results show the potential of these sensors in health care, environmental monitoring, food safety and homeland security for sensitive, specific, rapid, and affordable detection of bioagents/pathogens.
Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, United States.
Dhammanand J
DJ
Shirale
Mangesh A
MA
Bangar
Miso
M
Park
Marylynn V
MV
Yates
Wilfred
W
Chen
Nosang V
NV
Myung
Ashok
A
Mulchandani
D000537:Aluminum Oxide / Q000737:chemistry; D017123:Bacteriophage T7 / Q000737:chemistry; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D055664:Electrochemical Techniques; D004566:Electrodes; D004784:Environmental Monitoring / Q000379:methods; D007158:Immunologic Techniques / Q000295:instrumentation / Q000401:mortality*; D017909:Levivirus / Q000737:chemistry; D008954:Models, Biological; D053770:Nanowires / Q000737:chemistry / Q000821:virology; D011108:Polymers / Q000737:chemistry; D011758:Pyrroles / Q000737:chemistry; D014780:Viruses / Q000737:chemistry* / Q000302:isolation & purification; D014871:Water Microbiology; D014873:Water Pollutants / Q000737:chemistry / Q000302:isolation & purification
D011108:Polymers; D011758:Pyrroles; D014873:Water Pollutants; C067635:polypyrrole; D000537:Aluminum Oxide