Matrix solid phase dispersion extraction and high-performance liquid chromatography determination of metsulfuron-methyl in goat tissue samples

A highly selective matrix solid phase dispersion (MSPD) extraction purification method for the preconcentration of metsulfuron-methyl in goat tissues (liver, kidney, muscle and fat) was developed. A C18 sorbent based MSPD column was used for extraction of the analyte and extracted the metsulfuron-methyl residues from the sample using acidified ethyl acetate and methylene chloride mixture. The extracts were further purified by passing through the disposable silica mega bond –elut ® cartridges prior to quantification by HPLC on an Agilent Zorbax column (150mm length x 4.6mm id x 3.5µm). The HPLC detection was studied with UV detector at 246 nm. Acetonitrile and water (0.1% formic acid) 55:45 v/v was used as mobile phase at a flow rate of 0.7 ml min-1. The linearity of metsulfuron-methyl was observed over the concentration range 0.01 to 2 µg/mL and the regression coefficient (r) 0.9999. The mean recoveries of metsulfuron- methyl form tissues at 0.03 and 0.3 µg g-1 fortification levels were in the range of 86-97%.The limit of quantification and detection was established as 0.03 and 0.01 µg g-1 respectively. The proposed method was successfully applied for the determination of residues in goat liver, kidney, and muscle and fat samples.