Determination of diuretics and laxatives as adulterants in herbal formulations for weight loss

• Published in: Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment Vol. 30; no. 7; pp. 1230 - 1237
• Main Authors: Moreira, Ana Paula Lançanova, Motta, Monique Jung, Dal Molin, Thaís Ramos, Viana, Carine, de Carvalho, Leandro Machado
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis 01-07-2013; Taylor & Francis Ltd
• Subjects: adulterants; adulterated products; antidepressants; Biological and medical sciences; capillary zone electrophoresis; conductivity detection; Diuretics; Diuretics - analysis; Drug Contamination; Drug use; Electrophoresis, Capillary; Food industries; Fundamental and applied biological sciences. Psychology; furosemide; General aspects; herbal formulations; Herbal Medicine; Humans; hydrochlorothiazide; Laxatives; Laxatives - analysis; Limit of Detection; Methods of analysis, processing and quality control, regulation, standards; new methods; Weight control; Weight Loss; Zone electrophoresis; Capillary electrophoresis; herbal formulations; Weight loss; Conductivity; capillary zone electrophoresis; adulterants; Diuretic; Analysis method; Formulation; Control method; Detection; Adulteration; conductivity detection
• ISSN: 1944-0057; 1944-0049; 1944-0057
• DOI: 10.1080/19440049.2013.800649

A new method is described for the determination of the most common diuretic and laxative adulterants found in formulations of anorexics and antidepressants. The method is based on the separation of furosemide, hydrochlorothiazide, chlorthalidone and amiloride (diuretics), phenolphthalein (laxative), amfepramone (anorexic) and fluoxetine and paroxetine (antidepressants) by capillary zone electrophoresis with capacitively coupled contactless conductivity detection. The method showed a precision ranging from 1.9% to 6.9% for a concentration of 25 mg/L, 0.6% to 5.3% for a concentration of 50 mg/L and 1.6% to 6.0% for a concentration of 100 mg/L for all analytes. The accuracy was 99% for amiloride, 102% for chlorthalidone, 101% for hydrochlorothiazide, 101% for furosemide, 94% for phenolphthalein, 105% for fluoxetine, 114% for paroxetine and 117% for amfepramone. The method allowed the drugs to be determined in the formulations at concentrations higher than 5.1 mg/kg for amiloride, 7.7 mg/kg for chlorthalidone, 6.8 mg/kg for hydrochlorothiazide, 10.7 mg/kg for furosemide, 8.4 mg/kg for phenolphthalein, 11.0 mg/kg for fluoxetine, 9.4 mg/kg for paroxetine and 11.0 mg/kg for amfepramone. Three of the 26 analysed herbal formulations were found to be adulterated (not declared on the label) with the diuretic hydrochlorothiazide. Five other samples contained diuretics declared on the label on the formulation. Thus, a total of eight samples, which were marketed as natural products, contained diuretics (declared or not) on the formulation.