Simultaneous multi-mycotoxin determination in nutmeg by ultrasound-assisted solid–liquid extraction and immunoaffinity column clean-up coupled with liquid chromatography and on-line post-column photochemical derivatization-fluorescence detection

Abstract

A simple and sensitive analytical method based on ultrasound-assisted solid-liquid extraction and immunoaffinity column clean-up coupled with high performance liquid chromatography and on-line post-column photochemical derivatization-fluorescence detection (USLE-IAC-HPLC-PCD-FLD) has been developed for simultaneous multi-mycotoxin determination of aflatoxins B1, B2, G1, G2 (AFB1, AFB2, AFG1, AFG2) and ochratoxin A (OTA) in 13 edible and medicinal nutmeg samples marketed in China. AFs and OTA were extracted from nutmeg samples by ultrasonication using a methanol : water (80 : 20, v/v) solution, followed by an IAC clean-up step. Different USL extraction conditions, pre-processing ways for nutmeg sample and clean-up columns for mycotoxins, as well as HPLC-PCD-FLD parameters (mobile phase, column temperature, elution procedure, excitation and emission wavelengths) were optimized. This method, which was appraised for analyzing nutmeg samples, showed satisfactory results with reference to limits of detection (LODs) (from 0.02 to 0.25 μg kg(-1)), limits of quantification (LOQs) (from 0.06 to 0.8 μg kg(-1)), linear ranges (up to 30 ng mL(-1) for AFB1, AFG1 and OTA and 9 ng mL(-1) for AFB2 and AFG2), intra- and inter-day variability (all<2%) and average recoveries (from 79.6 to 90.8% for AFs and from 93.6 to 97.3% for OTA, respectively). The results of the application of developed method in nutmeg samples have elucidated that four samples were detected with contamination of AFs and one with OTA. AFB1 was the most frequently found mycotoxin in 30.8% of nutmeg samples at contamination levels of 0.73-16.31 μg kg(-1). At least two different mycotoxins were co-occurred in three samples, and three AFs were simultaneously detected in one sample.

Chemical diversity and pharmacological significance of the secondary metabolites of nutmeg (Myristica fragrans Houtt.)

“…A more recent method for detection of aflatoxins and ochratoxin A has been reported by Kong et al whereby HPLC coupled with post-column derivatization and fluorescence detection was employed to determine contamination levels in thirteen nutmeg products purchased in China (Kong et al 2013). …”

Impedimetric Aptasensor for Ochratoxin A Determination Based on Au Nanoparticles Stabilized with Hyper-Branched Polymer

“…OTA contamination is commonly detected by HPLC with fluorescent [15,16] or mass spectroscopy [17,18] detection coupled with alkaline or solid-phase extraction [19]. From other methods, immunochemical detection with SPR [20,21], electrochemical [21–25] and fluorescence [26–28] sensing can be mentioned (see also review [29] on immunochemical OTA detection and references cited).…”

Simultaneous determination of aflatoxins B1, B2, G1, G2inFructus Bruceaeby high-performance liquid chromatography with online postcolumn photochemical derivatization

“…It can be found that the LODs and LOQs in Refs. [33] and [34] were similar to ours since the same pretreatment and detection technique were used in these three works. Although LC-MS could achieve high sensitivity and selectivity, the data in our study were better than those obtained using LC-MS/MS methods in Refs.…”