Molecularly-imprinted polypyrrole-modified stainless steel frits for selective solid phase preconcentration of ochratoxin A.
A molecularly-imprinted polymer (MIP) was prepared by electropolymerization of pyrrole (Py) onto a stainless steel frit, using ochratoxin A (OTA) as the template, in order to make a micro solid phase preconcentration (microSPP) device. The OTA template was removed with 1% triethylamine (TEA) in methanol. Compared to non-imprinted polypyrrole (PPy), the molecularly-imprinted polypyrrole (MIPPy) enhanced the selective binding of OTA. The percentage recovery improved from 0 to 40% when the OTA sample solution was acidified with 1 M HCl (1% by volume). At a flow rate of 0.2 mL/min, maximum OTA binding was reached in 6 min after a total loading of 3.2 ng OTA. Final elution of the OTA was analyzed by high performance liquid chromatography (HPLC) with fluorescence detection, using 20:80 v/v acetonitrile-ammonia buffer (NH4Cl/NH3, 20 mM, pH 9.2) as the mobile phase. The MIPPy-microSPP-HPLC results clearly demonstrated that the MIPPy-microSPP device afforded selective preconcentration of OTA from red wine samples, at OTA concentration levels as low as 0.05 ppb, prior to HPLC analysis.
Yu
Jorn C C
JC
Department of Chemistry, Ottawa-Carleton Chemistry Institute, Carleton University, Ottawa, ON K1S 5B6, Canada.
Krushkova
Svetla
S
Lai
Edward P C
EP
Dabek-Zlotorzynska
Ewa
E
D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D002138:Calibration; D002851:Chromatography, High Pressure Liquid; D009793:Ochratoxins / Q000032:analysis*; D011108:Polymers / Q000737:chemistry*; D011758:Pyrroles / Q000737:chemistry*; D012015:Reference Standards; D012680:Sensitivity and Specificity; D013193:Stainless Steel / Q000737:chemistry*; D014920:Wine / Q000032:analysis / Q000592:standards
D009793:Ochratoxins; D011108:Polymers; D011758:Pyrroles; D013193:Stainless Steel; C025589:ochratoxin A; C067635:polypyrrole