Determination of Mepiquat Chloride in Grape, Wine and Juice by Liquid Chromatography with Electrospray Tandem Mass Spectrometry

Abstract

A simple and rapid method was developed for the analysis of mepiquat chloride in grape, wine and juice by high-performance liquid chromatography with electrospray tandem mass spectrometry (LC/MS/MS). Mepiquat chloride was extracted with waterῌmethanol (1 : 1). Extracted solution was adjusted to pH 10 with ammonia solution. A part of the extracted solution was cleaned up on a styrenedivinylbenzene (SDVB) cartridge for LC/MS/MS. The LC separation was performed on a C18 column (50 mmΐ2 mm i.d.) using 0.1 IPCC-MS7ῌmethanol (60 : 40) as the mobile phase at a flow rate of 0.2 mL/min. The mass spectral acquisition was done in the positive ion mode by applying selected reaction monitoring (SRM). The recoveries of mepiquat chloride from fresh grape, wine and juice fortified at 5 mg/kg and 50 mg/kg were 84.5ῌ96.1. The lower limit of quantification was 1 mg/kg. Fourteen fresh grape samples, 14 wines (white), 36 wines (red) and 11 juice samples were analyzed by this method. Mepiquat chloride was detected in 5 fresh grape samples, 3 wines (white) and 1 wine (red) at the level of 12.8ῌ199 mg/kg, 5.7ῌ47.7 mg/kg and 24.1 mg/kg, respectively.

An Overview of Hydrophobic Catalyst Over Styrene-Divinylbenzene Copolymer

“…Because of the high hydrophobicity of the SDB support, applications of this material have since gradually extended to many other fields, such as adsorption and separation (Liu et al, 2007;Rad and Louda, 2007;Weber et al, 2008;Bhardwaj et al, 2000;Fontanals et al, 2003;Gogoi et al, 2010), liquid chromagraphy Zhang et al, 2007;Merhar et al, 2001), catalyst support (Akaki, 2004;Struck and Widdecke, 1996;Rhodes et al, 1999;Leadbeater and Marco, 2002;Kao et al, 2003;Vanoye et al, 2011;Verma et al, 2010;Dai et al, 2009), and biotechnology and biomedicine (Liu et al, 2007). SDB was prepared by copolymerizing styrene with divinylbenzene by mixing equal weights of two materials.…”