[Detection of phenolphthalein added illegally into anti-obesity and healthcare food by TLC-FTIR].

OBJECTIVE:To establish a TLC-FTIR method for detection of western medicine phenolphthalein added illegally into anti-obesity and healthcare food. METHODS:The sample was extracted with anhydrous alcohol. The stationary phase was the GF254 aluminium alloy silica gel plates (10 cm x 20 cm) while the developing solvent was acetic ether: petroleum ether (60-90): methanol = 10: 6: 1. The sample volume was 2 microl. After primary screening by the UV lamp 254nm and self-made 2% NaOH test paper, the preparative technique of TLC was used to separate the component. Then the component was detected by FTIR and compared with the FTIR spectrogram of standard substance. RESULTS:Five of the ten samples contained phenolphthalein with the same testing results by using the TLC scanning and HPLC. CONCLUSION:The established method is accurate and reliable and can be used for detection of phenolphthalein illegally added into the products.