Validation of a RP-LC method for the simultaneous determination of isoniazid, pyrazinamide and rifampicin in a pharmaceutical formulation
ABSTRACT A simple and accurate liquid chromatographic method was developed and validated for estimation of isoniazid (ISN), pyrazinamide (PYR) and rifampicin (RIF) in combined dosage forms. Drugs were chromatographed on a reverse phase C18 column using a mobile phase gradient and monitored at the corresponding maximum of each compounds. Peaks were identified with retention time as compared with standards and confirmed with characteristic spectra using diode-array detector. Solution concentrations were measured on a weight basis to avoid the use of an internal standard. The method does not require any specific sample preparation except the use of a guard column. The method is linear (r(2)>0.999), precise (RSD%: 0.50% for ISN, 0.12% for PYR and 0.98% for RIF), accurate (overall average recovery yields: 98.55% for ISN, 98.51 for PYR and 98.56% for RIF) and selective. Due to its simplicity and accuracy the method is suitable for routine quality control analysis of antitubercolosis combination dosage form.
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- "In some cases there is no inclusion of an IS which compromises the robustness of the method   , some assays need relatively large volumes of sample and/or lacked sensitivity which limits their usefulness in pediatric studies where sample volumes are severely constrained    and other assays involve complex or very long extraction procedures thereby compromising throughput    . The aim of the work presented here was to develop a rapid and sensitive LC–MS/MS method for the quantification of RIF in human plasma and CSF samples. "
ABSTRACT: A highly sensitive and rapid liquid chromatography tandem mass spectrometry (LC-MS/MS) method has been developed to measure the levels of the antitubercular drug rifampicin (RIF) in human plasma and cerebrospinal fluid (CSF). The analyte and internal standard (IS) were isolated from plasma and CSF by a simple organic solvent based precipitation of proteins followed by centrifugation. Detection was carried out by electrospray positive ionization mass spectrometry in the multiple-reaction monitoring (MRM) mode. The assay was linear in the concentration range 25-6400ng/mL with intra- and inter-day precision of <7% and <8%, respectively. The validated method was applied to the study of RIF pharmacokinetics in human CSF and plasma over 25h period after a 10mg/kg oral dose.Journal of pharmaceutical and biomedical analysis 06/2012; 70(6):523-8. DOI:10.1016/j.jpba.2012.05.028 · 2.83 Impact Factor
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- "A microbondapak C18 column (Phenomenex, Torrance, CA) (250 × 4 mm i.d., 5 µm) was used in this study. This HPLC system can resolve rifampicin from other degradation product (Calleri et al., 2002). The rifampicin content in the same volume of LS (without dialysis) was analyzed as a total rifampicin loading. "
ABSTRACT: Rifampicin-encapsulated liposome suspensions were prepared by a chloroform-film method and converted to dry powders by freeze-drying with mannitol as a cryoprotectant. The liposome suspension had multilamellar nanovesicles with 50% rifampicin encapsulation. The liposome dry powder comprised particles with a mass median aerodynamic diameter of 3.4 mum, with 60% present as a fine particle fraction. Rifampicin-encapsulated liposomes were evidently nontoxic to respiratory associated cells, including bronchial epithelial cells, small airway epithelial and alveolar macrophages (AMs). Furthermore, the liposomes did not activate AMs to produce interleukin-1 beta, tumor necrosis factor-alpha, and nitric oxide at a level that would cascade to other inflammatory effects. The minimum inhibitory concentrations against Mycobacterium bovis was 0.2 and 0.8 microM for liposomes containing rifampicin and free rifampicin, respectively. The less negatively charged reconstituted liposome displayed the greatest activity against intracellular growth of M. bovis.Journal of Drug Targeting 12/2009; 17(10):751-62. DOI:10.3109/10611860903079462 · 2.72 Impact Factor
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- "Capillary electrophoresis with electrochemical detection using a 4-pyridyl hydroquinone self-assembled platinum micro-disk electrode (as working electrode) has been applied for the detection of isoniazid with a detection limit of 0.2 mM . Some other analytical methods that have been reported for the determination of isoniazid are: liquid chromatography with photometric detection  , flow injection=chemiluminescence detection   and UV-Vis spectrophotometry . However, most of these methods require sophisticated instruments or are time-consuming procedures which are tedious and also, do not have adequate sensitivity. "
ABSTRACT: A multi-walled carbon nanotube paste electrode (MWCPE) is prepared as an electrochemical sensor with high sensitivity and selectivity in responding to isoniazid. The electrochemical oxidation of isoniazid is investigated in buffered solution by cyclic and differential pulse voltammetry. The electrode is shown to be very effective for the detection of isoniazid in the presence of other biological reductant compounds. The electrochemical oxidation of cysteine, due to the high overvoltage, is completely stopped at the surface of MWCPE. The electrode exhibits a very good resolution between the voltammetric peak of isoniazid and the peaks of ascorbic acid (AA) and dopamine (DA). A resolution of more than 450 mV between the anodic peak potentials makes the MWCPE suitable for simultaneous detection of isoniazid in the presence of AA or DA in clinical and pharmaceutical preparations. Differential pulse voltammetry (DPV) is applied as a sensitive method for the determination of isoniazid. The linear range in these determinations is 1 × 10−6–1 × 10−3 M for isoniazid and the detection limit is 5 × 10−7 M. The electrode was applied to the simultaneous determinations in isoniazid and AA mixtures and also, isoniazid and DA mixture over a wide concentration range. The slope variation for the calibration curves of isoniazid (RSD) was less than 4.5% (based on ten measurements over a period of three months).Microchimica Acta 02/2007; 157(3):149-158. DOI:10.1007/s00604-006-0665-z · 3.72 Impact Factor