SIMULTANEOUS DETERMINATION OF TIGECYCLINE AND ITS POTENTIAL IMPURITIES BY A STABILITY-INDICATING RP-HPLC-UV DETECTION TECHNIQUE

Objective: Stability representing the RP-HPLC method was established for synchronized quantification of Tigecycline and its impurities. This method was confirmed for its applicability to both tablet dosage and bulk drug forms. Methods: Intended for an isocratic elution, a mobile phase containing methanol: 10 mmol Triethylamine Buffer mixture (75:25 v/v, pH 6.1) was used at 1 ml/min flow rate and Agilent ZORBAX Eclipse XDB C18 (250 mm × 4.6 mm, 5 μm) column. Results: At 231 nm as wavelength, high-pitched peaks of Tigecycline (Tig) and its impurities (1and2) were detected at 6.55, 8.73 and 4.87 min correspondingly. The linearity of tigecycline and its impurities (impurity-1 and 2 and) were estimated with ranging from 75–450 µg/ml for Tigecycline and 1–6 µg/ml for both impurity 1 and 2. The corresponding recognition limits (LOD and LOQ) of the tigecycline and its impurities were originated to be (1.37,0.047 and 0.071 µg/ml) and (4.15, 0.143 and 0.126 µg/ml). Conclusion: The technique was effectively stretched for stability signifying studies under different stress conditions. Justification of the method was done as per the current ICH guidelines.

A Rapid HPLC Method for the Simultaneous Determination of Organic Acids and Furans: Food Applications

Concerns over the potential adulteration of commercially produced foods give rise to a requirement for a simple and fast analytical method capable of quantifying potential adulterants. This work demonstrates a simple HPLC method tailored to detect major organic acids and furans within ingredients in commercial food products, for example, pomegranate molasses, balsamic vinegar, and apple cider vinegar. The relative importance of this method is in its simplicity and its use of an environmentally friendly aqueous mobile phase under isocratic conditions, providing results in a less than 20 min runtime. The chromatographic separation was achieved using an Acclaim® OA, 5 µm, 120 Å (4.0 × 250 mm) column; a UV-DAD detector set at 210 nm; and a 200 mM Na2SO4 mobile phase with 0.55 mL/L methanosulfonic acid as a pH modifier. The method was then validated by quantifying the concentration of acetic acid, formic acid, citric acid, and hydroxymethyl furfural (HMF) in pomegranate molasses, balsamic vinegar, and apple cider vinegar commercial products. The concentration of acetic acid and HMF in balsamic vinegar was 80.380 mg/mL (±1.272 mg/mL) and 2.153 mg/mL (±0.021 mg/mL), respectively. The apple cider vinegar was composed only of acetic acid with a concentration of 44.139 mg/mL (±0.053 mg/mL). The concentrations of citric acid and HMF were 123.425 mg/mL (±2.502 mg/mL) and 11.382 mg/mL (±0.582 mg/mL), respectively, in pomegranate molasses. Furthermore, this method is also capable of determining various organic acids and furans in biomass: levulinic acid, formic acid, furfurals, diformylfuran, and gamma-valerolactone.

TELMISARTAN AND AZELNIDIPINE QUANTIFICATION EMPLOYING HPLC STRATAGEM; STABILITY INVESTIGATION ON TELMISARTAN AND AZELNIDIPINE

Objective: The focus of our research was to create a fairly sensitive HPLC stratagem for determining telmisartan (TLM) and azelnidipine (AEL) in bulk and tablet types. Methods: Analysis of TLM and AEL was performed on a “C18 Kromasil stationary column (5 µm, 250 mm × 4.6 mm)”. The mobile phase was made of 0.1M NaH2PO4 solution (pH 3.5) and methanol at a comparative volume ratio of 50% each. The analysis of TLM and AEL was isocratic, with the flow velocity adjusted at 1.0 ml/min and indeed, the TLM and AEL analysis was done at 256 nm using a PDA device sensor. TLM and AEL were stressed with acid, peroxide, dry heat, alkali, and sunlight-induced settings. Results: The retention/elution periods for the TLM and AEL were observed at 2.225 min and 3.178 min, respectively. The HPLC stratagem developed have a straight-line relation with relative concentrations in the ranges of 20-60 µg/ml for TLM and 4-12 µg/ml for AEL. The LOQ’s for TLM and AEL were 0.2516 μg/ml and 0.0871 μg/ml, respectively. The validation investigational findings done for TLM and AEL with the established sensitive HPLC stratagem were passed out in conformity with the ICH standards. Conclusion: The established sensitive HPLC stratagem was shown as competent for the quality check of bulk samples of TLM and AEL throughout batch release as well as in the course of TLM and AEL stability investigations.

HPLC determination of Escitalopram in tablet dosage forms

Purpose: A simple, specific, precise, and accurate reversed phase liquid chromatographic (RP-LC) method has been developed for the determination of Escitalopram in tablet dosage form. Methods: The chromatographic separation was achieved on a LiChrosorb C18, 250 mm x 4.6 mm, 5 μm column at a detector wavelength of 270 nm and a flow rate of 1.0 ml/min. The mobile phase was composed of methanol, acetonitrile (70:30 v/v). The retention time of Escitalopram was 5.49 min. The method was validated for the parameters like specificity, linearity, precision, accuracy, limit of quantitation and limit of detection. Results: The method was found to be specific as no other peaks of impurities and excipients were observed. The square of correlation coefficient (R2) was 0.9999 while relative standard deviations were found to be <2.0%. Conclusion: The proposed RP-LC method can be applied for the routine analysis of commercially available formulations of Escitalopram.

Pharmacokinetics Study of Rabdosia Rubescens Drop Pills Based on UPLC-MS/MS

Background: Rabdosia rubescens drop pills have the effects of clearing away heat and toxin, detumescence, relieving pain. Objective: A simple and sensitive method for simultaneous determination of oridonin, ponicidin, and rosmarinic acid in rat plasma was developed based on ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Methods: Chromatographic separation was performed on a Waters ACQUITY UPLC BEH C18 column (2.1 × 100 mm, 1.7 µm) with a mobile phase consisting of water containing 0.2% formic acid (mobile phase A) and methanol (mobile phase B) at a flow rate of 0.3 mL/min over a total run time of 3.8 min. All analytes were measured with optimized multiple reaction monitoring (MRM) in positive and negative ion ESI mode. Results: The transitions of oridonin, ponicidin, rosmarinic acid, diphenhydramine, and chloramphenicol were 365.3→347.3, 363.3→345.2, 359.0→160.9, 256.0→167.2, and 321.1→151.9, respectively. The linear ranges were 1-256 ng/mL for ponicidin and rosmarinic acid and 2-512 ng/mL for oridonin. The validated method wasstable and reliable. There was no significant difference in the half-life (t1/2) of the three analytes at three doses. The area under the curve (AUC0-t) and peak concentration (Cmax) of the three analytes decreased linearly in each dose range, and the linear correlation R2 of each analyte under the three doses was greater than 0.95. Conclusion: This method was successfully applied to pharmacokinetic studies of oridonin, ponicidin, and rosmarinic acid in rat plasma after intragastric administration of Rabdosia rubescens drop pills.

Development of High Performance Liquid Chromatographic Estimation of Domperidone and Lansoprazole

The combination of Domperidone and Lansoprazole is very useful in Gastro-esophageal disinfection (Dyspepsia). These methods provide means to separate the components characterize and quantify the components. An accurate, precise, specific and simple HPLC method was developed for simultaneous estimation of Domperidone and Lansoprazole. By this method retention time, linearity and accuracy data is respectively found for Domperidone and Lansoprazole. Mobile phase was prepared by mixing 51 volume of Acetonitrile and 49 volume of Ammonium Acetate (51:49 V/V) then 25mg each of Domperidone and Lansoprazole was dissolved in small volume of Acetonitrile: Ammonium Acetate (51:49 V/V) separately. Retention time was recorded 4.330 ± 0.003 minute and 5.820 ± 0.003 minute for Domperidone and Lansoprazole with 1.0 ml/min flow rate. The low value of % R.S.D indicates that this method is precise and accurate. Thus it can be concluded that the proposed method was good approach for obtaining reliable result.