title: Polypyrrole modified stainless steel frits for on-line micro solid phase extraction of ochratoxin A.
abstract: Polypyrrole (PPy) was electrochemically synthesized on stainless steel frits as a sorbent for the micro solid phase extraction (muSPE) of ochratoxin A (OTA). Using 20 microl of standard solution under a fast flow rate of 0.5 ml/min, 80% recovery of OTA was achieved in the concentration range from 0.1-10 pg/mul. This good recovery was achieved within a short residence time of 1.2 s. A binding capacity of 1 ng OTA was estimated for each PPy-modified frit, or 2 ng OTA for two frits in series. The bound OTA could be pulsed eluted (PE) with 20 microl of 1% triethylamine in acetonitrile. On-line coupling of this PPy-on-a-frit and PE technique to high performance liquid chromatography (HPLC) was straightforward. On-line muSPE-PE-HPLC results clearly demonstrated the capability of PPy-on-a-frit to bind OTA in the presence of red wine, beer, and orange juice components.
authors.affiliation: Ottawa-Carleton Chemistry Institute, Department of Chemistry, Carleton University, Ottawa, ON, K1S 5B6, Canada.
authors.forename: Jorn C C
authors.initials: JC
authors.lastname: Yu
authors.forename: Edward P C
authors.initials: EP
authors.lastname: Lai
mesh_terms: D001628:Beverages / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D009793:Ochratoxins / Q000302:isolation & purification*; D011108:Polymers / Q000737:chemistry*; D011758:Pyrroles / Q000737:chemistry*
chemical_list: D009793:Ochratoxins; D011108:Polymers; D011758:Pyrroles; C025589:ochratoxin A; C067635:polypyrrole