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K C Jindal

Publications and source records attributed to K C Jindal.

12 recordsLinked to original sources
PubMed2006

LC and LC-MS study of stress decomposition behaviour of isoniazid and establishment of validated stability-indicating assay method.

Isoniazid was subjected to different ICH prescribed stress conditions of thermal stress, hydrolysis, oxidation and photolysis. The drug was stable to dry heat (50 and 60 degrees C). It showed extensive decomposition under hydrolytic conditions, while it was only moderately sensitive to oxidation stress. The solid drug turned intense yellow on exposure to light under accelerated conditions of temperature (40 degrees C) and humidity (75% RH). In total, three major degradation products were detected by LC. For establishment of stability-indicating assay, the reaction solutions in which different degradation products were formed were mixed, and the separation was optimized by varying the LC conditions. An acceptable separation was achieved using a C-18 column and a mobile phase comprising of water:acetonitrile (96:4, v/v), with flow rate and detection wavelength being 0.5 ml min(-1) and 254 nm, respectively. The degradation products appeared at relative retention times (RR(T)) of 0.71, 1.34 and 4.22. The validation studies established a linear response of the drug at concentrations between 50 and 1000 microg ml(-1). The mean values (+/-R.S.D.) of slope, intercept and correlation coefficient were 35,199 (+/-0.88), 114,310 (+/-4.70) and 0.9998 (+/-0.01), respectively. The mean R.S.D. values for intra- and inter-day precision were 0.24 and 0.90, respectively. The recovery of the drug ranged between 99.42 and 100.58%, when it was spiked to a mixture of solutions in which sufficient degradation was observed. The specificity was established through peak purity testing using a photodiode array detector. The method worked well on application to marketed formulation of isoniazid, and a fixed-dose combination containing isoniazid and ethambutol HCl. It was even extendable to LC-MS studies, which were carried out to identify the three degradation products. The m/z values of the peaks at RR(T) 0.71 and RR(T) 1.34 matched with isonicotinic acid and isonicotinamide, respectively. The product appearing at RR(T) 4.22 was isolated using preparative LC-MS, and turned out to be a yellow compound that was identified as isonicotinic acid N'-(pyridyl-4-carbonyl)-hydrazide based on mass, FTIR and (1)H/(13)C NMR spectral data. The same was indicated to be responsible for discolouration of isoniazid bulk drug substance and formulations, which is a familiar problem. The mechanism of formation of the said compound is outlined.

Biological Assay↗
PubMed2005

Mechanistic explanation to the catalysis by pyrazinamide and ethambutol of reaction between rifampicin and isoniazid in anti-TB FDCs.

Rifampicin and isoniazid are known to interact with each other in solid formulation environment to yield isonicotinyl hydrazone (HYD). In earlier studies, this reaction was indicated to be catalyzed by pyrazinamide and ethambutol hydrochloride, the two other co-drugs present in oral anti-tuberculosis fixed-dose combination (FDC) formulations. Accordingly, the present study was carried out to understand the catalytic role of pyrazinamide and ethambutol hydrochloride on the reaction between rifampicin and isoniazid. For the purpose, organic bases and amides similar in structure to pyrazinamide and ethambutol hydrochloride were combined individually with rifampicin and isoniazid. The compounds employed were pyrazine, piperdine, pyrollidine, pyridine, triethylamine, diisopropylethylamine, picolinamide, benzamide, ethylenediamine, ethanolamine, diethanolamine, and triethanolamine. An additional study was also carried out in the presence of free base of ethambutol. The mixtures were exposed to accelerated stability test condition of 40 degrees C/75% RH for 15 d. The nature of the products formed and the changes in relative concentrations of the drugs and products were followed by HPLC. The drugs showed different extent of degradation, yielding HYD, and in some cases degradation products of rifampicin. The results confirmed the catalytic role of pyrazinamide and ethambutol hydrochloride. The catalysis is postulated to involve intra-molecular proton transfer during transhydrazone formation process, entailing a tetrahedral mechanism.

Amides↗
PubMed2005

Drug-drug interaction studies on first-line anti-tuberculosis drugs.

The purpose of this study was to carry out drug-drug compatibility studies on pure first line anti-tuberculosis drugs, viz., rifampicin (R), isoniazid (H), pyrazinamide (Z), and ethambutol hydrochloride (E). Various possible binary, ternary, and quaternary combinations of the four drugs were subjected to accelerated stability test conditions of 40 degrees C and 75% relative humidity (RH) for 3 months. For comparison, parallel studies were also conducted on single drugs. Changes were looked for in the samples drawn after 15, 30, 60, and 90 days of storage. Analyses for R, H, and Z were carried out using a validated HPLC method. The E was analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS), as it does not absorb in ultraviolet (UV). All single pure drugs were relatively stable and showed only 3%-5% degradation under accelerated conditions for 3 months. However, significant interactions were observed in case of the drug mixtures. In particular, ternary and quaternary drug combinations containing R and H along with Z and/or E were very unstable, showing 90%-95% and 70%-75% loss of R and H, respectively. In all these cases, isonicotinyl hydrazone (HYD) of 3-formylrifamycin and H was found to be the major degradation product. In case of RE and RZE mixtures, where H was absent, 3-formylrifamycin was instead the key degradation product. Another unidentified peak was observed in the mixture containing RZE. Apart from these chemical changes, considerable physical changes were also observed in pure E and the mixtures containing E, viz., RE, ZE, RHE, RZE, and RHZE. In addition, significant physical changes associated with noteworthy loss of H and E were also observed in mixtures containing HE and HZE. The present study thus amply shows that the four primary anti-tuberculosis drugs, when present together, interact with each other in a multiple and complex manner.

Antitubercular Agents↗
PubMed2004

Overestimation of rifampicin during colorimetric analysis of anti-tuberculosis products containing isoniazid due to formation of isonicotinyl hydrazone.

When present together in fixed-dose combinations (FDC) of anti-tuberculosis drugs, rifampicin (R) and isoniazid (H) interact with each other to form isonicotinyl hydrazone (HYD). In a preliminary study, this product was found to possess similar colorimetric spectrum to that of rifampicin. Therefore, an investigation was undertaken to determine interference of HYD during analysis of rifampicin in FDC products by colorimetry. For the purpose, standard plots were constructed for rifampicin and HYD at 475 nm, the wavelength maximum for both the compounds. The plots were linear in the range of 10-100 microg/ml. Molar absorptivity values for rifampicin and HYD were 15279 and 5034, respectively. It indicated that HYD possessed one-third absorptivity to that of rifampicin. The analysis of combinations of rifampicin and HYD revealed that rifampicin could be overestimated to a maximum extent of 33%, while interference varied at other relative ratios of the two compounds. This was also confirmed by colorimetric and HPLC analysis of a degraded marketed product and samples from a dissolution study. Thus this investigation suggests that any method devoid of interference of HYD should be preferred for analysis of rifampicin, whenever it is present along with isoniazid.

Antitubercular Agents↗
PubMed2004

Interference of isonicotinyl hydrazone in the microbiological analysis of rifampicin from anti-tuberculosis FDC products containing isoniazid.

Microbiological assay is a sensitive method for the estimation of rifampicin (R). In the present study, interference due to isonicotinyl hydrazone (HYD), an interaction product of R and isoniazid (H), was checked during microbiological analysis of R, employing Bacillus subtilis and Sarcina lutea. The assays were done by disc diffusion method. Both R and HYD showed linear log response curves in the range of 0.01-10microg. In the presence of HYD, R was overestimated when tested against S. lutea and underestimated in case of B. subtilis. The same extent and type of interference was observed on assay of a marketed anti-tuberculosis fixed-dose combination product, subjected to accelerated stability testing (40 degrees C/75% RH) for 1 month. This means that response of organisms used in microbiological assay of R might vary in the presence of HYD, with possibility of incorrect conclusions. Therefore, the study suggests that before a microbiological method involving a particular organism is extended to the determination of R in FDC formulations containing H, it should be tested for the influence of HYD and used only if non-interfering.

Antitubercular Agents↗
PubMed1994

Dissolution test method for rifampicin-isoniazid fixed dose formulations.

A dissolution procedure for a rifampicin-isoniazid combination formulation was evaluated using 0.1 N hydrochloric acid solution and 0.4% (w/v) sodium lauryl sulphate solution as dissolution media. Rifampicin and isoniazid along with degradation components were chromatographed using reversed-phase liquid chromatography on a 10 microns octadecylsilica column using methanol-0.01 M disodium hydrogen phosphate (70:30, v/v; pH 4.6 +/- 0.1) as mobile phase. The detection was carried out at 254 nm. The data obtained indicate that the dissolution medium consisting of 0.4% (w/v) sodium lauryl sulphate solution is suitable for such a combination. The degradation observed in dissolution medium consisting of 0.1 N hydrochloric acid was 10-23%.

Capsules↗
PubMed1993

Determination of diltiazem hydrochloride in human serum by high-performance liquid chromatography.

A simple and sensitive reversed-phase high-performance liquid chromatographic method for the determination of diltiazem in human serum has been developed. The method involves a one-step deproteinization of serum for sample clean-up using acetonitrile. A LiChrosorb RP-8 column (30 cm x 4.1 mm I.D.) was eluted isocratically with acetonitrile-0.01 M dibasic sodium phosphate (40:60, v/v) containing 0.01% triethanolamine. Diltiazem was monitored at 237 nm and 0.1 a.u.f.s. The completion time for assay was less than 15 min, and the lower limit of quantitation was 10 ng/ml for a 100-microliters injection volume. Using this method, the pharmacokinetic parameters were calculated from a serum concentration versus time profile of diltiazem.

Acetonitriles↗
PubMed1993

Reversed-phase high-performance liquid chromatography of ketorolac and its application to bioequivalence studies in human serum.

A reversed-phase high-performance liquid chromatographic assay was used to study the bioequivalence of the anti-inflammatory drug (+/-)-ketorolac in human volunteers. Following deproteinization of human serum with 5% zinc sulphate solution, ketorolac was chromatographed on a 10-microns octadecylsilica column using acetonitrile-water as mobile phase and ultraviolet detection at 313 nm. Under these conditions the method was reproducible with a coefficient of variation of less than 5%. The assay procedure was linear in the range 0.25-1.5 micrograms/ml, with a sensitivity of 0.01 micrograms/ml ketorolac. The recovery of ketorolac from serum ranged from 90 to 95%.

Analgesics↗
PubMed1981

Drugs on a medical campus. III. Drug use among nursing and paramedical personnel.

Fifty nurses and 50 paramedical staff working in the Rajendra Hospital and Medical College, Patiala, were studied by means of a structured, self-report questionnaire. The life-time prevalence of drug use among nurses was comparatively low--55%, compared to 81% among the paramedical staff. Current use of drugs as shown by the 30-day prevalence rate was also very low among the nurses, a majority of whom restricted themselves to using tranquillizers and sedatives for the specific purpose of relaxation or inducing sleep; only a few had experimented with alcohol, cannabis, and tobacco. On the other hand, the most commonly used drug among the paramedical personnel was alcohol, followed by sedatives, tranquillizers, cannabis and tobacco, most of them taking the drug for social reasons or for the thrills from the effects of the drug. This is also reflected in the comparatively higher number of paramedicals who felt that they would probably continue to use these drugs in the future, as also the fact that there were a few dependent users of opium and narcotics in this group.

Adult↗
PubMed1980

Drugs on a medical campus. II. Drug use among faculty members.

One hundred out of a total of 207 members of the faculty of Medical College, Patiala, selected by a process of random sampling were covered in the present survey. They were divided into two groups--the senior consultants and the junior doctors. The lifetime prevalence rate for drug use was 78.9 per cent, and the commonest drugs used were alcohol and tranquilizers, followed by sedatives, stimulants, tobacco and cannabis. However, current use as shown by the 30-day prevalence rate showed that only three drugs--alcohol, tobacco and tranquilizers--are commonly used. More of the senior doctors were single-drug users (44 per cent) compared to only 20 per cent among the junior doctors, who experimented with a larger variety of drugs and took them more frequently than the seniors. Enquiry into the reasons for drug use revealed further differences between the two groups; a majority of the senior physicians stated that they took drugs to help them obtain relief from their tensions, whereas among the younger group a considerable number took them for thrills or out of curiosity. A majority of the physicians felt they would continue to use alcohol, tobacco and tranquilizers in the future, whereas they would not take cannabis, opium or narcotics.

Adult↗