simultaneous determination of six benzodiazepines in spiked soft drinks by high performance liquid chromatography with ultra violet detection (hplc-uv)

a high performance liquid chromatographic method with ultra violet detection for simultaneous analysis of six benzodiazepines (bzds) (chlordiazepoxide, diazepam, clonazepam, midazolam , flurazpam and lorazepam) has been developed for forensic screening of adulterated non-alcoholic drinks. samples were analyzed after a simple procedure for preparation using ph adjustment and filtering. isocratic elution on a c18 column (250mm × 4.6 mm, 5μm) in the temperature 45ºc with a mobile phase consisting of 15mm phosphate buffer: methanol (50:50 v/v) at a flow rate 1.4 ml/min has been done. the column eluent was monitored with a uv detector at 245 nm. this allowed a rapid detection and identification as well as quantization of the eluting peaks. calibration curves for all drugs in the range of 0.5- 10 µg/ ml that all the linear regression and has more than 0.996. recovery rates for the bzds were in the range 93.7- 108.7%. the limits of detection were calculated between 0.01- 0.02 µg/ ml. also, the limits of quantification were 0.03- 0.05 µg/ml. within-day and between -day coefficient of variation for all bzds at all concentrations in the range of 0.45 - 7.69 % was calculated. the procedure can provide a simple, sensitive and fast method for the screening of six bzds in adulterated soft drinks in forensic analysis.