Thiolated Salmonella antibody immobilization onto the gold surface of piezoelectric quartz crystal

• Published in: Biosensors & bioelectronics 1998-11, Vol.13 (10), p.1091-1097
• Main Authors: Park, In-Seon, Kim, Namsoo
• Format: Article
• Language: English
• Subjects: Antibodies, Bacterial - chemistry; antibody-coated sensor; Biological and medical sciences; Biosensing Techniques; Biosensors; Biotechnology; Cross-Linking Reagents; Crystallization; Food industries; Food Microbiology; Fundamental and applied biological sciences. Psychology; Gold; Methods. Procedures. Technologies; Quartz; quartz crystal microbalance; Reproducibility of Results; Salmonella; Salmonella - immunology; Salmonella typhimurium - immunology; Sulfhydryl Compounds - chemistry; sulfo-LC-SPDP; Surface Properties; thiolated antibody immobilization; Various methods and equipments
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/S0956-5663(98)00067-0

An improved antibody-coated sensor system based on quartz crystal microbalance analysis on Salmonella spp. was developed making use of thiolated antibody immobilization onto one gold electrode of the piezoelectric quartz crystal surface. The best results in sensitivity and stability were obtained with the thin layer of a thiol-cleavable, heterobifunctional cross-linker, sulfosuccinimidyl 6-[3-(2-pyridyldithio)propionamido]hexanoate (sulfo-LC-SPDP). The long bridge of this reagent could function as a spacer, facilitating antibody- Salmonella interaction on the gold electrode. After the addition of a S. typhimurium suspension into a reaction cell with 0.1 M sodium phosphate buffer, pH 7.2, the resonant frequency decreased conspicuously. The time required for maximum frequency shift was about 30∼90 min. Sensor response was observed for the microbial suspensions ranging from 9.9×10 5 to 1.8×10 8 CFU/ml.