00000nam a22000004a 4500 UP-1685675941131395089 Buklod 20240104121518.0 m |o d | ta 240104s2023 xx r |||| u| d PHARM rda eng LG 993.5 2023 P5 N36 Naoe, Angelle Mae L. author Determination and quantification of phenolphthalein found in herbal weight loss products bought from online merchants using high performance liquid chromatography mass spectrometry Angelle Mae L. Naoe, Lui Gen S. Catague, Robert Benjamin C. Uygen ; adviser, Reymond Fernando B. Yu. Manila: Department of Pharmacy, College of Pharmacy, University of the Philippines Manila 2023 viii, 85 leaves 28 cm. text rdacontent unmediated rdamedia volume rdacarrier Thesis (Bachelor of Science in Pharmaceutical Sciences)--University of the Philippines Manila, August 2023. Available only for consultation with authors/thesis adviser. Available only to those bound by confidential agreement. A high performance liquid chromatography-mass spectrometry (HPLC-MS) method was developed and validated for the analysis of phenolphthalein spiked in herbal weight loss supplements purchased from online merchants. HPLC-MS parameters such as mobile phase composition, flow rate, column temperature, gradient elution program, and lens voltage were optimized one parameter at a time. The optimum chromatographic conditions were achieved using a gradient of 2.5 mM ammonium formate: 0.05% formic acid: water buffer as Mobile Phase A and acetonitrile as Mobile Phase B, operated under a 0.35 mL/min flow rate in a column with a 35°C temperature. The lens voltage was set at 0 DL Voltage, -90 Qarray DC, and 52 Qarray RF. The limits of detection and quantitation of the method were 25 ng/mL and 50 ng/mL, respectively. The developed method was linear (R? = 0,9913) with a range of 50-1000 ng/mL. The mean percent recoveries were 98.57 107.35%. Meanwhile, the %RSD of the intra- (n = 3) and inter-day (n =9 for 3 days) precision were 0.94-1.64% and 0.75-1.80%, respectively, signifying that the developed method was accurate and precise. Moreover, matrix and carryover effects were found to be negligible, with matrix effects at 97.76-108.29%. The developed and validated method was used for the analysis of phenolphthalein in 20 herbal weight supplements purchased from two online merchants. Phenolphthalein was detected in 5 samples, with contents ranging from 0.5 196-104.6194 mg/unit. The developed method can be used for the detection or determination of phenolphthalein adulterated into herbal weight loss supplements. Phenolphthalein Determination. High performance liquid chromatography. Phenolphthalein Herbal. Weight loss. High performance liquid chromatography. Phenolphthalein Merchant High-performance liquid chromatography Mass Spectrometry. Catague, Lui Gen S. author. Uygen, Robert Benjamin C. author . Yu, Reymond Fernando B. adviser . FI UP UPMNL PHARM LG 993.5 2023 P5 N36 Thesis