Analytical Sciences


Abstract − Analytical Sciences, 18(4), 397 (2002).

Rapid Diagnosis of M.tuberculosis Using a Piezoelectric Immunosensor
Fengjiao HE  and LiudeZHANG
Department of Chemistry and ChemicalEngineering, Hunan University, Hunan, Changsha, 410082, P. R.China
A piezoelectric immunosensor was developedfor detecting Mycobacteria Tuberculosis (M. TB). Protein Awas modified onto a silver-coated piezoelectric quartz-crystal sensor.Antibodies could be bond onto the crystal surface in an ordered orientationthrough protein A. An impendence analyzer was employed to record theadmittance-frequency curve. The experimental results showed a successfuland less-rigid bonding of protein A and antibodies. Compared with othertraditional detection methods of TB, the method suggested in this paper wassensitive, selective and effective. The nonspecific response was limitedby using control antibody-rabbit anti-honey bee venom (anti-HBV). Aglycine-HCl buffer solution (pH = 2.4) was used to release antibodies froma crystal coated with protein A, and 0.5 mg/mL anti-TB was used to removeTB from a crystal that was bonded by an antibody. Good reusability wasexhibited. Spike samples of sputum and saliva from normal people with andwithout adding M. tuberculosis were diagnosed using the proposedmethod. Good results were obtained.