Detection of antistreptolysin O antibody: application of an initial rate method of latex piezoelectric immunoassay.
Latex plezoelectric immunoassay (LPEIA) is a new latex immunoassay using a plezoelectric quartz crystal (Kurosawa et al. Chem. Pharm. Bull. 1990, 38, 1117). This assay requires no immobilization of antigen or antibody on an electrode surface of a plezoelectric crystal, while the immobilization is indispensable for ordinary immunoassays using a plezoelectric crystal as a microbalance. The present paper improves a previous method (end-point analysis) by introducing the initial rate method using a batch cell; reduction of assay volume (1.2 mL) and shortening of assay time (2-3 min) were achieved. This assay was applied to the detection of antistreptolysin O antibody (ASO) in serum. The frequency change was proportional to the ASO concentration up to 1040 IU mL-1, and the method has good sensitivity for actual clinical application. The volume of serum required for the assay was 0.02 mL. Twenty-four clinical specimens were analyzed with this LPEIA, and the values obtained were compared with those obtained with a turbidimetric latex agglutination method. The correlation coefficient between these values was 0.950 (P < 0.01).
Muratsugu
M
M
Department of Laboratory Medicine, School of Medicine, Asahikawa Medical College, Japan.
Kurosawa
S
S
Kamo
N
N
D000371:Agglutination; D000818:Animals; D000906:Antibodies / Q000032:analysis* / Q000276:immunology; D001426:Bacterial Proteins; D002417:Cattle; D003461:Crystallography; D004563:Electrochemistry; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D007840:Latex; D011791:Quartz; D013301:Streptolysins / Q000276:immunology*
D000906:Antibodies; D001426:Bacterial Proteins; D007840:Latex; D013301:Streptolysins; C025964:streptolysin O; D011791:Quartz