response surface methodology for modelling and determination of catechin in pistachio green hull using surfactant-based dispersive liquid–liquid microextraction followed by uv–vis spectrophotometry

A rapid and simple approach for the preconcentration and determination of catechin from pistachio green hull samples has been proposed by surfactant-assisted dispersive liquid–liquid microextraction followed by uv–vis spectrophotometry (sadllme/uv–vis). this method involved the formation of a catechin complex with cetylpyridinium chloride (cpc) as cationic surfactant, and subsequently, dllme was applied to extract the catechin–cpc complex into chloroform. different parameters affected the extraction efficiency were optimized by central composite design (ccd) and response surface methodology (rsm). in optimum condition, the calibration curve was linear in the range of 0.4–5 µg ml− 1 of catechin with correlation coefficient of 0.9982. the relative standard deviation based on five replicated analyses of 1 µg ml− 1 catechin was 1.85%. the proposed method was successfully applied for preconcentration and determination of trace amounts of catechin in pistachio hull samples.