Affinity sensor using 3-aminophenylboronic acid for bacteria detection.
Boronic acid that can reversibly bind to diols was used to detect bacteria through its affinity binding reaction with diol-groups on bacterial cell walls. 3-aminophenylboronic acid (3-APBA) was immobilized on a gold electrode via a self-assembled monolayer. The change in capacitance of the sensing surface caused by the binding between 3-APBA and bacteria in a flow system was detected by a potentiostatic step method. Under optimal conditions the linear range of 1.5×10(2)-1.5×10(6) CFU ml(-1) and the detection limit of 1.0×10(2) CFU ml(-1) was obtained. The sensing surface can be regenerated and reused up to 58 times. The method was used for the analysis of bacteria in several types of water, i.e., bottled, well, tap, reservoir and wastewater. Compared with the standard plate count method, the results were within one standard deviation of each other. The proposed method can save both time and cost of analysis. The electrode modified with 3-APBA would also be applicable to the detection of other cis-diol-containing analytes. The concept could be extended to other chemoselective ligands, offering less expensive and more robust affinity sensors for a wide range of compounds.
Wannapob
Rodtichoti
R
Trace Analysis and Biosensor Research Center, Center for Innovation in Chemistry, Department of Chemistry, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand.
Kanatharana
Proespichaya
P
Limbut
Warakorn
W
Numnuam
Apon
A
Asawatreratanakul
Punnee
P
Thammakhet
Chongdee
C
Thavarungkul
Panote
P
D058491:Bacterial Load / Q000295:instrumentation*; D015374:Biosensing Techniques / Q000295:instrumentation*; D001897:Boronic Acids / Q000737:chemistry*; D003217:Conductometry / Q000295:instrumentation*; D025802:Electric Capacitance; D004867:Equipment Design; D019544:Equipment Failure Analysis; D012475:Salmonella / Q000302:isolation & purification*; D013211:Staphylococcus aureus / Q000737:chemistry* / Q000302:isolation & purification*; D014871:Water Microbiology
D001897:Boronic Acids; C028592:3-aminobenzeneboronic acid