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  • Author or Editor: A. Gomes Barreto x
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Abstract  

The present work proposes evaluation of the gelatinization processes of starch by means of DSC coupled with a photovisual system. The use of DSC, TG and DTA for a fast and efficient evaluation of the starch is suggested. The DSC curves of starch gels with water contents of 20, 30, 40 and 50% (mass/v) exhibited different phase transitions, corresponding to the gelatinization processes at the different water contents for the different lots. The DSC-photovisual system confirmed calorimetric behaviour differences between the starch lots studied.

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Abstract  

The present work reports studies of the thermal behaviour of some anti-hypertensive drugs. Their purities were determined by DSC and specialized pharmacopeial methods. The activation energy values suggest the following sequence of satability: nifedipine>propanolol hydrochloride>captoril. Analysis of the DSC data indicated that the degrees of purity of nifedipine, captopril and propanolol hydrochloride were similar to those found by pharmacopeial methods BP 93 and USP 23. The simplicity, speed and low operational costs of thermal analysis justify its application in the quality control of pharmaceutical drugs.

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