A new method for the determination of trace amount of crystal violet from aqueous solutions by spectrophotometry after cloud point extraction has been proposed. The optimum extraction and reaction conditions,such as pH,reagents concentration and effect of time and temperature,have been studied with the nonionic surfactant triton X-114.The maximum absorption wavelength of crystal violet is 579 nm.Linearity was obeyed in the range of 32~700 ng/mL with the limit of detection of 9.8 ng/mL.The enrichment factor was 20 for crystal violet.The relativ...