Determination of ochratoxin A in human urine by solid-phase microextraction coupled with liquid chromatography-fluorescence detection.
A new method for the determination of ochratoxin A (OTA) in human urine samples has been developed using solid-phase microextraction (SPME) interfaced with liquid chromatography-fluorescence detection (LC-FD). This method is simpler and cheaper compared to the most widely adopted clean-up procedures for OTA extraction from urine (usually based on immunoaffinity columns). Briefly, urine samples, diluted 1:5 with phosphate buffer (10 mM, pH 3), were partitioned against chloroform and the aqueous phase extracted by a polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber. The fiber was then "statically" desorbed, through a SPME interface, into a LC system operating in isocratic conditions. The linear range investigated in urine was 0.01-1 ng/ml. Within-day R.S.D.% in urine spiked at 0.1 and 1 ng/ml were 3.9 and 1.9, respectively, whereas the between-days R.S.D.% were 5.5 and 3.0, respectively. The limits of detection (LOD) and quantitation (LOQ) calculated at a signal-to-noise ratio of 3 and 10 (noise calculated peak to peak on a blank chromatogram at the OTA retention time) were 0.01 and 0.05 ng/ml, respectively.
Vatinno
Rosa
R
Dipartimento di Chimica, Università degli Studi di Bari, Via E. Orabona 4, I-70126 Bari, Italy.
Aresta
Antonella
A
Zambonin
Carlo G
CG
Palmisano
Francesco
F
D002853:Chromatography, Liquid; D004129:Dimethylpolysiloxanes / Q000737:chemistry; D006801:Humans; D006868:Hydrolysis; D007120:Immunochemistry; D007202:Indicators and Reagents; D009793:Ochratoxins / Q000652:urine*; D012828:Silicones / Q000737:chemistry; D052617:Solid Phase Microextraction; D012997:Solvents; D013050:Spectrometry, Fluorescence; D013343:Styrenes
D004129:Dimethylpolysiloxanes; D007202:Indicators and Reagents; D009793:Ochratoxins; D012828:Silicones; D012997:Solvents; D013343:Styrenes; C076011:1,3-diethenylbenzene; C025589:ochratoxin A; C013830:baysilon