IDENTIFICATION OF GLIADIN PRESENCE IN PHARMACEUTICAL PRODUCTS

Celiac disease is characterized by hypersensitivity to the alcohol-sol uble wheat proteins called gliadins. Total avoidance of gliadin is the lifelong treatment for such patients. However, wheat gliadins are oft en present as impurities in industrial starch commonly used in the pre paration of different pharmaceutical products. Therefore, some drugs m ight contain gliadin, which can be dangerous for sensitive patients if taken in large amounts or used permanently. The purpose of this study was to develop a sensitive, reliable assay that is specific for the d etection of gliadins in pharmaceutical products. Gliadins were extract ed here using sodium dodecyl sulfate rather than 70% ethyl alcohol, wh ich has been the traditional solvent. This gliadin extract was utilize d in a dot-blot assay that incorporated an antigliadin antibody develo ped in rabbit and labeled with peroxidase. 4-Chloro-1-naphthol was use d as a peroxidase-specific substrate. Isolated wheat gliadin was used as the positive control. Dilution experiments showed that the lower le vel of sensitivity for the assay was in the range of 0.0045 mg/ml of g liadin, which is a concentration level lower than that suggested for a gluten-free diet. The assay developed here revealed that 71.2% of 59 prescription and nonprescription drugs tested contained gliadin in the amount detected by our dot-blot assay. The prescription drugs tested were among the top 50 most frequently dispensed in U.S. community phar macies. The nonprescription drugs were among those that constitute the largest sales in the United States. The results showed that the simpl e dot-blot assay developed here can be used for pharmaceutical testing performed either by hospital laboratories or by patients themselves.