Method Development and Validation for Pyrogallol Content Quantification by HPLC in Trimetazidine Dihydrochloride

Trimetazidine dihydrochloride (TD) is an anti-ischemic drug that is used to effectively treat angina pectoris symptoms. During the manufacture of TD from gallic acid a process related impurity, pyrogallol, is produced. Up to the present time, no appropriate method has been proposed for the detection and analysis of pyrogallol in the TD at the level of threshold of toxicological concern. Therefore, in this investigation, a reliable and reproducible HPLC method was developed for the detection and analysis of pyrogallol in the TD. The method was validated in full compliance with the recommendations of the International Harmonization Council. Regression analysis indicated a correlation coefficient value of 0.9990 for pyrogallol between 6.3 ppm and 31.5 ppm. The LOD was 1.89 ppm and LOQ was 6.3 ppm for pyrogallol. Good recovery (accuracy) was observed in the range of 98.34% to 118.54 % with an RSD value (precision) of 0.150%. Pyrogallol analysis in batches TD material has demonstrated the good performance of the method. The process is therefore useful in the identification and evaluation of pyrogallol content in drug substance of TD.

Comparison of high-performance thin layer chromatography/UV-densitometry and UV-derivative spectrophotometry for the determination of trimetazidine in pharmaceutical formulations

New methods for assaying trimetazidine dihydrochloride on the basis of thin layer chromatography and spectrophotometry are proposed and compared in the paper. In HPTLC/UV-densitometry, separation is achieved by using a mobile phase composed of ammonia-methanol (30:70, V/V) on silica gel HPTLC plates F254. Quantification using a non-linear calibration curve is accomplished by densito-metric detection at 230 nm. Derivative spectrophotometric determination of trimetazidine dihydrochloride is carried out from the fourth derivative of the absorbance at 233 nm in peak-zero mode. Statistical comparison led to the conclusion that there is no significant difference between the two studied methods and, moreover, that they demonstrate satisfactory accuracy and precision for routine applications.

INFLUENCE OF TRIMETAZIDINE METABOLIC THERAPY ON CONNECTIVE TISSUE METABOLISM IN EXPERIMENTAL DIFFUSE ISCHEMIC NECROTIC CARDIOSCLEROSIS IN RATS WITH DIFFERENT RATES OF HYPOXIA RESISTANCE

<p>Background. The change in metabolism of the connective tissue elements of heart is the central chain in<br />pathogenesis of diffuse ischemic necrotic cardiosclerosis (DINC), which occurs after repeated epinephrine injury<br />of myocardial tissues.<br />Objective. This study proves that trimetazidine (TM) metabolic therapy has a protective effect on the<br />development of DINC in rats with different rates of hypoxia resistance.<br />Methods. Male white rats were divided into three groups due to the different rates of hypoxia resistance by<br />means of the method of hypobaric hypoxia: rats with low, middle and high rates of hypoxia resistance. Each<br />group was divided into equal subgroups: a control group, a DINC group (injections of epinephrine hydrotartrate<br />(0,5 mg/kg of body weight) and calcium gluconate (5 mg/kg of body weight) two times), a control group administrated<br />with trimetazidine dihydrochloride (10 mg/kg of body weight), a DINC group treated with TM every day<br />(10 mg/kg of body weight) for all period of observation. Concentration of protein-bound oxyproline in blood<br />serum was evaluated on the 7th, 14th and 30th days after the pathology simulation. Histological examination of<br />Masson trichrome staining of myocardium was performed on the 30th days after the pathology simulation.<br />Results. DINC increased the concentration of protein-bound oxyproline in blood serum on the 7th, 14th and<br />30th days after the pathology simulation, and followed by metabolic imbalances in diffuse connective tissue elements,<br />which are rich in collagens. DINC+TM increased the concentration of protein-bound oxyproline in blood<br />serum less intensively.<br />Conclusions. The intensity of metabolic imbalances in diffuse connective tissue elements is the highest in<br />the low resistant animals to hypoxia. Those results are confirmed by histological examination of the myocardium<br />of rats with different resistance to hypoxia. Fibrotic regions in myocardium are rich in collagens. It has been<br />revealed that the most pronounced therapeutic effect of TM is observed in animals with low resistance to hypoxia,<br />slight – in animals with medium resistance to hypoxia, and the lowest – in animals with high resistance to<br />hypoxia.<br />KEY WORDS: hypoxia, heart, diffuse cardiosclerosis, trimetazidine, oxyproline.</p>