Assessment of gas chromatography methodology approach for the trace evaluation of carcinogenic impurity, methyl chloride, in trimetazidine dihydrochloride.

OBJECTIVE: A simple and robust head space/gas chromatography with flame ionisation sensor (HS/GC/FIS) approach for the trace evaluation of carcinogenic impurity, methyl chloride, in trimetazidine dihydrochloride (TRD) drug ingredient and its formulation is described. METHOD: This HS/GC/FIS approach was based on separation and analysis of CH3Cl content on DB-624 [75.0m - length, 0.53mm - internal diameter, 3.0µm - film thickness] column using nitrogen as carrier gas flowing through the column at 3mL/min stream rate. Detection of eluted CH3Cl was accomplished with flame ionization sensor at a set temperature of 260̊C. RESULTS: The optimised HS/GC/FIS methodological approach was thoroughly validated, demonstrating that it was linear with range of 5.0ppm to 1508.4ppm, sensitive with detection limit of 1.65ppm and quantification limit of 5.01ppm, reproducible with RSD values of 2.10-2.35%, accurate with recoveries of 81.9-99.0%, robust with percent variation of 7.5-12.22% with respect to changes in oven temperature, injector temperature, detector temperature and practical for regular TRD quality control. CONCLUSION: The findings revealed that with this optimised HS/GC/FIS methodological approach, the trace amounts of carcinogenic impurity (methyl chloride) in TRD drug ingredient and formulation could be successfully measured.

Metabolic study of trimetazidine using ultra-high performance liquid chromatography-tandem mass spectrometry

Abstract In the present study, the application of ultra-high performance liquid chromatography-tandem mass spectrometry allowed us to study of known-as well as hitherto unknown-trimetazidine (TMZ) metabolites in human urine and to propose their renal excretion profiles. Urine samples from a healthy volunteer were analyzed at baseline and at 0-4 h, 4-8 h, 8-12 h, and 12-24 h after a single dose of TMZ. A dilute-and-shoot procedure was used as sample treatment before separation. Full-scan spectra of possible metabolites were acquired. Additionally, product ion scan spectra of precursor ions of interest were also acquired at two collision energies. Intact TMZ was a major excretion product, with a maximum concentration at 4-8 h after administration. Moreover, five minor metabolites were observed, namely trimetazidine-N-oxide (M1), N-formyl trimetazidine (M2), desmethyl-trimetazidine O-sulfate (M3), desmethyl-trimetazidine O-glucuronide (M4), and desmethyl-trimetazidine-N-oxide-O-glucuronide (M5). Metabolite M5 has not previously been reported. Excretion curves were constructed based on the chromatographic peak areas of specific mass transitions (precursor ion > product ion) related to each of the detected metabolites

A new combination of naringin and trimetazidine protect kidney Mitochondria dysfunction induced by renal Ischemia / Reperfusion injury in rat

Abstract Ischemia/reperfusion (IR) injury leads to overproduction of Reactive Oxygen Species (ROS), and disrupts membrane potential that contributes to cell death. The aim of this study was to determine if naringin (NAR), trimetazidine (TMZ) or their combination, protect the kidney mitochondrial from IR injury. Forty rats were randomly allocated into five groups, harboring eight rats each: Sham, IR, NAR (100 mg/kg), TMZ (5 mg/kg) and NAR plus TMZ. Ischemia was induced by obstructing both renal pedicles for 45 min, followed by reperfusion for 4 hours. The mitochondria were isolated to examine the ROS, Malondialdehyde (MDA), Glutathione (GSH), mitochondrial membrane potential (MMP) and mitochondrial viability (MTT). Our findings indicated that IR injury resulted in excessive ROS production, increased MDA levels and decreased GSH, MMP and MMT levels. However, NAR, TMZ or their combination reversed these changes. Interestingly, a higher protection was noted with the combination of both, compared to each drug alone. We speculate that this combination demonstrates a promising process for controlling renal failure, especially with the poor clinical outcome, acquired with NAR alone. This study revealed that pretreatment their combination serves as a promising compound against oxidative stress, leading to suppression of mitochondrial stress pathway and elevation of GSH level.

Mucoadhesive elementary osmotic pump tablets of trimetazidine for controlled drug delivery and reduced variability in oral bioavailability.

The objectives of this work was preparation and evaluation of the mucoadhesive elementary osmotic pump tablets of trimetazidine hydrochloride to achieve desired controlled release action and augmentation of oral drug absorption. The drug-loaded core tablets were prepared employing the suitable tableting excipients and coated with polymeric blend of ethyl cellulose and hydroxypropyl methylethylcellulose E5 (4:1). The prepared tablets were characterized for various quality control tests and in vitro drug release. Evaluation of drug release kinetics through model fitting suggested the Fickian mechanism of drug release, which was regulated by osmosis and diffusion as the predominant mechanism. Evaluation of mucoadhesion property using texture analyzer suggested good mucoadhesion potential of the developed osmotic systems. Solid state characterization using Fourier-transform infrared spectroscopy, differential scanning calorimetry and powder X-ray diffraction spectroscopy confirmed the absence of any physiochemical incompatibilities between drug and excipients. Scanning electron microscopy analysis showed the smooth surface appearance of the coated tablets with intact polymeric membrane without any fracture. In vivo pharmacokinetic studies in rabbits revealed 3.01-fold enhancement in the oral bioavailability vis-à-vis the marketed formulation (Vastarel MR®). These studies successfully demonstrate the bioavailability enhancement potential of the mucoadhesive elementary osmotic pumps as novel therapeutic systems for other drugs too.

The prevalence of trimetazidine use in athletes in Poland: excretion study after oral drug administration.

Stimulants, together with anabolic androgenic steroids, are regarded as one of the most popular doping substances in sport. Owing to a great variety of these substances and new designer drugs being introduced to the market, each year the World Anti-Doping Agency (WADA) updates the list of substances and methods prohibited in sport. On 1 January 2014, a new doping agent - trimetazidine (TMZ) - was added to the WADA Prohibited List. TMZ, a substance prohibited in competition, is classified in the S6b Specified Stimulant Group. TMZ is used as a well-known cardiologic drug with confirmed biochemical and clinical activity. According to knowledge of the pharmacology and mechanism of TMZ action, TMZ can be used by athletes to improve physical efficiency, especially in the case of endurance sports. This study presents the phenomena of TMZ use by Polish athletes involved in anti-doping control in the WADA-accredited laboratory in Warsaw (Poland) between 2008 and 2013. Samples were taken from the athletes of such disciplines as cycling, athletics, and triathlon. Moreover, the elimination study of TMZ has been conducted to establish the change of TMZ concentration in urine sample after oral administration of a single or double (during the long-term therapy) dose. TMZ was monitored in urine samples by gas chromatography-mass spectrometry-nitrogen phosphorus detection (GC-MS-NPD).

Doping control analysis of trimetazidine and characterization of major metabolites using mass spectrometric approaches.

Since January 2014, the anti-anginal drug trimetazidine [1-(2,3,4-trimethoxybenzyl)-piperazine] has been classified as prohibited substance by the World Anti-Doping Agency (WADA), necessitating specific and robust detection methods in sports drug testing laboratories. In the present study, the implementation of the intact therapeutic agent into two different initial testing procedures based on gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) is reported, along with the characterization of urinary metabolites by electrospray ionization-high resolution/high accuracy (tandem) mass spectrometry. For GC-MS analyses, urine samples were subjected to liquid-liquid extraction sample preparation, while LC-MS/MS analyses were conducted by established 'dilute-and-inject' approaches. Both screening methods were validated for trimetazidine concerning specificity, limits of detection (0.5-50 ng/mL), intra-day and inter-day imprecision (<20%), and recovery (41%) in case of the GC-MS-based method. In addition, major metabolites such as the desmethylated trimetazidine and the corresponding sulfoconjugate, oxo-trimetazidine, and trimetazidine-N-oxide as identified in doping control samples were used to complement the LC-MS/MS-based assay, although intact trimetazidine was found at highest abundance of the relevant trimetazidine-related analytes in all tested sports drug testing samples. Retrospective data mining regarding doping control analyses conducted between 1999 and 2013 at the Cologne Doping Control Laboratory concerning trimetazidine revealed a considerable prevalence of the drug particularly in endurance and strength sports accounting for up to 39 findings per year.

Stability-indicating determination of trimetazidine dihydrochloride inthe presence of two of its related substances using a direct GC/MS method.

A novel, simple, direct, and selective stability- indicating GC/MS procedure was developed for the determination of the anti-ischemic drug trimetazidine dihydrochloride (TMZ) in the presence of two of its related substances (potential impurities), namely, 2,3,4-trimethoxybenzyl alcohol (T1) and 2,3,4-trimethoxybenzaldehyde (T2). The method involved resolution of the undeilvatized compounds using a 100% dimethylpolysiloxane (Rtx-1) capillary column, and MS detection was carried out in the electron-impact mode. The peaks of the three compounds eluted at retention times 11.69, 11.92, and 15.47 min for T1, T2, and TMZ, respectively. Quantification of the parent drug TMZ was based on measuring its peak area. The reliability and analytical performance of the proposed method, including linearity, range, precision, accuracy, selectivity, detection, and quantification limits, were statistically validated. The calibration curve of TMZ was linear over the range 100-600 µg/mL. The proposed method was successfully applied to the assay of TMZ in several commercially available pharmaceutical formulations with recoveries not lessthan 96.2%.

Chemiluminescence determination of trimetazidine via inducing the aggregation of gold nanoparticles.

A simple, rapid and sensitive chemiluminescence (CL) method combined with flow injection analysis was developed for the determination of trimetazidine. Trimetazidine was found to significantly increase the CL signal arising from N-bromosuccinimide-luminol reaction in the presence of gold nanoparticles. The enhanced CL intensity was proportional to trimetazidine concentration in the range of 0.01-5.0 µg/mL, with a limit of detection (3 sb) of 6.7 ng/mL. The relative standard deviation was 2.8% for 11 repetitive measurements of 0.1 µg/mL trimetazidine solution. The practicality of the method was evaluated by determining trimetazidine in pharmaceutical formulations and in spiked human serum samples. Moreover, the possible CL reaction mechanism was also discussed.

New nonextractive and highly sensitive high-performance liquid chromatographic method for determination of paroxetine in plasma after offline precolumn derivatization with 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole.

New nonextractive and simple offline precolumn derivatization procedures have been proposed, for the first time, for the trace determination of paroxetine (PXT) in human plasma by HPLC with fluorescence detection. Trimetazidine (TMZ) was used as an internal standard. Plasma samples were treated with acetonitrile for protein precipitation and then derivatized with 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole in borate buffer of pH 8 at 70 degrees C for 30 min. Separations of the derivatized PXT and TMZ were performed on a Nucleosil CN column using a mobile phase consisting of acetonitrile-10 mM sodium acetate buffer (pH 3.5)-methanol (47 + 47 + 6, v/v) at a flow rate of 1.0 mL/min. The derivatized samples were excited at 470 nm and monitored at an emission wavelength of 530 nm. Under the optimum chromatographic conditions, a linear relationship with good correlation coefficient (r = 0.9998, n = 7) was found between the peak area ratio and PXT concentrations in the range of 5-600 ng/mL. The LOD and LOQ were 1.37 and 4.14 ng/mL, respectively. The intraday and interassay precisions were satisfactory; the RSD did not exceed 4.2%. The accuracy of the method was proved by recovery of PXT from spiked human plasma at levels of 97.28-104.38 +/- 0.41-3.62%. The proposed method had high throughput, as the analysis involved a simple sample pretreatment procedure and short run time (< 10 min). The results demonstrated that the method would have a great value when it is applied in the therapeutic monitoring of PXT.

Computer-assisted optimization and validation of LC analysis of trimetazidine dihydrochloride and its impurities.

Trimetazidine dihydrochloride is an anti-anginal drug, which possesses protective properties against ischemia inducing heart damage. In this paper, a new procedure for liquid chromatographic analysis was successfully developed, optimized, and applied in assessment of trimetazidine dihydrochloride content and its impurities, Y-145, Y-235, and Y-234 at most 1.0%, 0.2%, and 0.2%, respectively, in commercially available pharmaceutical preparation containing 35 mg of trimetazidine dihydrochloride. The retention behavior of trimetazidine dihydrochloride and its impurities is investigated by using several stationary and mobile phases to settle a simple, sensitive, and precise RP-HPLC method. The separation conditions are optimized by DryLab 2000 Plus Chromatography Optimization Software version 3.5.00. Separations are performed on PurospherSTAR RP18 endcapped (150 x 4.6 mm, 5 microm particle size) column at 20 degrees C with UV detection at 210 nm. The mobile phase composition is acetonitrile-aqueous phase (10 mmol/L disodium hydrogenphosphate and 2 mmol/L sodium dihydrogen phosphate, pH 7.6) (30:70 v/v). Afterwards, the method is validated; the important statistical parameters for selectivity/specificity, linearity, precision, limit of detection, and quantitation are defined. The recovery value of the trimetazidine dihydrochloride is 98.06%, and the content of impurities is 0.23% for Y-145, less than 0.02% for Y-235, and less than 0.01% for Y-234. In addition, this method is used for analyzing trimetazidine dihydrochloride and its impurities in pharmaceuticals and bulk drug.

Trimetazidine revisited: a comprehensive review of the pharmacological effects and analytical techniques for the determination of trimetazidine.

Trimetazidine (TMZ) is an effective and well-tolerated antianginal drug that possesses protective properties against ischemia-induced heart injury. Growing interest in metabolic modulation in recent years urged an up-to-date review of the literature on TMZ. This review consists of two major sections: (1) comprehensive and critical information about the pharmacological effects, mechanism of action, pharmacokinetics, side effects, and current usage of TMZ, and (2) developments in analytical techniques for the determination of the drug in raw material, pharmaceutical dosage forms, and biological samples.

Determination of trimetazidine dihydrochloride in the presence of its acid-induced degradation products.

Three methods are presented for the determination of trimetazidine dihydrochloride in the presence of its acid-induced degradation products. The first method was based on measurement of first-derivative D1 value of trimetazidine dihydrochloride at 282 nm over a concentration range of 8.00-56.00 microg/mL with mean percentage accuracy of 99.80+/-1.17. The second method was based on first derivative of the ratio spectra DD1 at 282 nm over the same concentration range with the percentage accuracy of 99.14+/-0.68. The third method was based on separation of trimetazidine dihydrochloride from its acid-induced degradation products followed by densitometric measurement of the spots at 215 nm. The separation was performed on silica gel 60 F254 using methanol-ammonia (100+/-1.5, v/v) as mobile phase. This method was applicable for determination of the intact drug in the presence of its degradation products over a concentration range of 2.00-9.00 microg/spot with mean percentage accuracy of 99.86+/-0.92. The proposed methods were successfully applied for the determination of trimetazidine dihydrochloride in bulk powder, laboratory-prepared mixtures containing different percentages of degradation products, and pharmaceutical dosage forms. The validity of results was assessed by applying the standard addition technique. The results obtained agreed statistically with those obtained by the reported method.

Quantitative determination of some pharmaceutical piperazine derivatives through complexation with iron(III) chloride.

A simple, accurate and sensitive spectrophotometric method has been developed for the determination of three pharmaceutical piperazine derivatives, namely ketoconazole (KC), trimetazidine hydrochloride (TMH) and piribedil (PD). This method is based on the formation of yellow orange complexes between iron(III) chloride and the investigated drugs. The optimum reaction conditions, spectral characteristics, conditional stability constants and composition of the water soluble complexes have been established. The method permits the determination of KC, TMH and PD over a concentration range 1-15, 1-12 and 1-12 microg ml(-1), respectively. Sandell sensitivity is found to be 0.016, 0.013 and 0.013 microg cm(-2) for KC, TMH and PD, respectively. The method was sensitive, simple, reproducible and accurate within +/-1.5%. The method is applicable to the assay of the three drugs under investigation in different dosage forms and the results are in good agreement with those obtained by the official methods (USP and JP).

Trimetazidine: stability indicating RPLC assay method.

An accurate, specific and reproducible reversed phase liquid chromatographic method for the determination of trimetazidine hydrochloride in presence of its degradation products is reported. The mobile phase consisted of water-acetonitrile-triethylamine (90:10:0.1, v/v/v) adjusted with o-phosphoric acid to a pH of 3.3. Chromatography was performed using C-18 column at a flow rate of 1.0 ml/min and the drug along with its degraded products was detected at 270 nm. The calibration curve of trimetazidine hydrochloride in methanol was linear in the range 500-3000 ng. The mean value of correlation coefficient, slope and intercept were 0.99859 &# 0.001, 17.7986 &# 0.0709 and 482.56 &# 147.03, respectively. The limits of detection and quantitation were 5 and 20 ng, respectively. The recovery of trimetazidine hydrochloride was about 99-100%. This method was utilized to analyze trimetazidine hydrochloride from conventional tablets and controlled release pellets in the presence of commonly used excipients.

Stability indicating HPTLC determination of Trimetazidine as bulk drug and in pharmaceutical formulations.

A simple, selective, precise and stability-indicating high-performance thin-layer chromatographic method of analysis of trimetazidine hydrochloride both as a bulk drug and in formulations is reported. The mobile phase composition was n-butanol-water-methanol-ammonia (20%) (14:0.2:0.2:2, v/v/v/v). Densitometric analysis of trimetazidine hydrochloride was carried out in the absorbance mode at 254 nm. the calibration curve of trimetazidine hydrochloride in methanol was linear in the range 400 -- 2400 ng. The mean value of correlation coefficient, slope and intercept were 0.99815 and #61617;0.001, 0.4849 and #61617;0.001 and 31.633 and #61617;5.996 respectively. The limits of detection and quantitation were 50 and 80 ng respectively. The recovery of trimetazidine hydrochloride was about 98 -- 100%. This method was utilized to analyze trimetazidine hydrochloride from conventional tablets and controlled release pellets in the presence if commonly used excipients.