Development and validation of an analytical method for the analysis of Sterigmatocystin in roasted coffee beans and black pepper using liquid chromatography-tandem mass spectrometry.

Sterigmatocystin (STC) is a toxic and potentially carcinogenic fungal toxin found in a variety of food commodities. This study describes the development of an analytical method to determine STC in roasted coffee beans and black pepper using ultra performance liquid chromatography (UPLC) coupled with triple quadrupole tandem mass spectrometry (MS/MS). 13C18-STC was used as internal standard. STC was extracted with a mixture of acetonitrile/water, diluted with a buffer, followed by purification with a solid-phase extraction and an immunoaffinity column prior to the UPLC-MS/MS analysis. Two multiple reaction monitoring (MRM) transitions were employed, one for quantification and one for confirmation of STC. The UPLC-MS/MS analytical method was validated with respect to selectivity, linearity, sensitivity, accuracy, precision, recovery, and stability. Calibration curves were linear over a concentration range 25-2,500 pg mL-1 with correlation coefficients (r) > 0.998. The method limit of quantification for STC in roasted coffee beans and black pepper was 0.10 µg kg-1. The accuracy and precision of the analytical method were acceptable within 15% at all quality control levels. This method was suitable to determine STC levels because of its selectivity, precision, and accuracy. The method was successfully applied to roasted coffee beans and black pepper samples.

Determination of butyltins, phenyltins and octyltins in foods with preservation of their moieties: A critical review on analytical methods.

Tributyltin and triphenyltin have been extensively applied in anti-fouling paints since the 1960s. Hence, organotin compounds (OTCs), especially butyltins and phenyltins, in seafood has been of concern for decades. Even though the "International Convention on the Control of Harmful Anti-Fouling Systems on Ships, 2001" entered into force internationally in 2008 and prohibited the use of OTCs in anti-fouling paints used on ships, the analysis of OTCs in seafood was not commonly included in routine monitoring programmes. Besides, species of triphenyltin, including triphenyltin hydroxide and acetate, have been used as pesticides and may accumulate in food. Moreover, the European Food Safety Agency established a group tolerable daily intake for tributyltin, dibutyltin, triphenyltin and dioctyltin in 2004 as they exert their immunotoxic effects by similar mode of action and potency. Therefore, suitable methods are needed to analyze butyl-, phenyl- and octyl-tins simultaneously in food without affecting their moieties. This review aims to provide background information in this area.