Amino-bonded silica as stationary phase for liquid chromatographic determination of cyclopiazonic acid in fungal extracts.
A new high-performance liquid (HPLC) chromatographic method is described for cyclopiazonic acid (CPA) determination in fungal cultures on a propylamino-bonded stationary phase with a CH3CN/CH3COONH4 buffer as mobile phase. Retention of CPA on propylamino modified silica under acidic conditions (protonated amino groups and deprotonated CPA) is governed by a mixed ion-exchange-reversed-phase mechanism. In addition to non-polar (hydrophobic) interactions, polar interactions with the surface silanols are also possible and become important as the polarity of the mobile phase decreases. A detection limit of 25 pg of CPA standard is obtained that represents an improvement of more than two orders of magnitude compared to existing HPLC procedures. UV-detector response was linear to 200 ng of CPA. Fungal extracts can be analysed after a simple dilution step with UV diode array detection that provides peak identity/purity assessment. The suitability of the proposed method as a rapid confirmatory test to assess the toxigenic potential of different Aspergillus and Penicillium strains is demonstrated by the analysis of 54 fungal extracts.
Monaci
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Dipartimento di Chimica, Università degli Studi di Bari, Italy.
Aresta
A
A
Palmisano
F
F
Visconti
A
A
Zambonin
C G
CG
D000588:Amines / Q000737:chemistry; D001230:Aspergillus / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D007211:Indoles / Q000032:analysis*; D010407:Penicillium / Q000737:chemistry*; D012680:Sensitivity and Specificity; D012822:Silicon Dioxide / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet
D000588:Amines; D007211:Indoles; D012822:Silicon Dioxide; C000543:cyclopiazonic acid