A selective HPLC method for determination of lercanidipine in tablets

A Design-assisted Spectrofluorometric Method Utilizing a One-pot Fluorescent Probe for the Quantitation of some Calcium Channel Blockers

Based on their reaction with highly fluorescent carbon quantum dots (CQDts), a precise and reliable spectrofluorometric approach was developed for the determination of three calcium channel blockers. The studied drugs are: lercanidipine, nimodipine and nifedipine. (CQDts) were produced using a one-step hydrothermal method with ascorbic acid as the carbon source. The produced CQDts were capped by alcohol to create yellow emitters displaying a high fluorescence emission at 524 nm when excited at 325 nm. The fluorescence intensity of CQDts was noticeably quenched by each of the three calcium channel blockers. The relation between their concentrations and fluorescence quenching is linear over the concentration range of 0.5-20 µg/mL for each of the three drugs. A full factorial design was used to optimize the effect of variable factors. Therefore, under optimum experimental design conditions, the detection limits for lercanidipine, nimodipine, and nifedipine were 0.11 ± 1.09, 0.10 ± 0.25 and 0.12 ± 0.71 µg/mL, respectively. The LOQ was 0.33, 0.30, and 0.37 µg/mL respectively. The quenching of fluorescent CQDts occurred through the inner filter effect (IFE) for nimodipine, while it was mixed with dynamic quenching for lercanidipine and nifedipine. The proposed method was effectively used to determine the cited drugs in their pharmaceutical products and had an acceptable level of precision. The selectivity of the CQDts system towards the studied drugs was examined indicating no interference from interfering species.

Development of three ecological spectroscopic methods for analysis of betrixaban either alone or in mixture with lercanidipine: greenness assessment

Three eco-friendly spectrophotometric methods were developed for determination of the novel anticoagulant drug, betrixaban (BTX). The first method (method A) was based on direct analysis of BTX at 229.4 nm on the zero-order spectrum using methanol as the optimum solvent. While the second method (method B) was based on measuring difference absorption value (ΔA) of BTX at 335 nm, which was obtained from pH-induced spectral difference (difference spectra of BTX in 0.1 M NaOH versus 0.1 M HCl). The third method (method C) was based on measurement of the first-derivative amplitudes of BTX and its co-administered Ca channel blocker lercanidipine (LER) at 304 and 229 nm for simultaneous assay of BTX and LER, respectively. All methods were linear over concentration ranges of 1.0-20.0 and 8.0-80.0 µg ml^-1 for BTX in methods A and B, respectively, and of 1.0-20.0 and 1.0-25.0 µg ml^-1 for BTX and LER, respectively, in method C. The three methods were fully validated and assessed for greenness by three metrics: analytical eco-scale, green analytical procedure index and Analytical GREEnness metrics. The results indicated the validity and greenness of the proposed methods. Moreover, the methods were applied to assay the studied analytes in their dosage forms with high percentage of recovery and low percentage of relative s.d. values.

Development and validation of reversed phase high-performance liquid chromatography method for estimation of lercanidipine HCl in pure form and from nanosuspension formulation

Aim:

Quantitative estimation of lercanidipine HCl in bulk material as well as from nanosuspension formulations via a developed reverse phase HPLC method.

Materials and Methods:

Optimized chromatographic condition was used to achieve separation on a Kromasil (100-5c18 250 × 4.6 mm) column using Shimadzu HPLC system. The mobile phase consisted of a mixture of acetate buffer (20 mM pH 4.5) and acetonitrile in the ratio of 10:90, v/v. It is pumped through the chromatographic system at a flow rate of 1 ml/min. The detection was carried out at 240 nm using ultraviolet-visible spectrophotometry detector. The method was validated as per Q2 (R1) guidelines, and suitability of the developed method was established by optimized nanosuspension formulation.

Results:

The method is specific to lercanidipine (RT: 7.7 min), and has ability to resolve the analyte peak from excipient interferences. It is linear (regression coefficient: 0.9993), accurate (average recovery: 100%), and passed all the system suitability requirements.

Conclusion:

Developed method was found applicable for evaluation of drug content, content uniformity, and analyzing samples of dissolution studies of nanosuspension.

Flow injection chemiluminescence determination of lercanidipine based on N-chlorosuccinimide-eosin Y post-chemiluminescence reaction

A novel post-chemiluminescence (PCL) reaction was discovered when lercanidipine was injected into the CL reaction mixture of N-chlorosuccinimide with alkaline eosin Y in the presence of cetyltrimethylammonium bromide (CTAB), where eosin Y was used as the CL reagent and CTAB as the surfactant. Based on this observation, a simple and highly sensitive PCL method combined with a flow injection (FI) technique was developed for the assay of lercanidipine. Under optimum conditions, the CL signal was linearly related to the concentration of lercanidipine in the range 7.0 × 10(-10) to 3.0 × 10(-6)  g/mL with a detection limit of 2.3 × 10(-10) g/mL (3σ). The relative standard deviation (RSD) was 2.1% for 1.0 × 10(-8) g/mL lercanidipine (n = 13). The proposed method had been applied to the estimation of lercanidipine in tablets and human serum samples with satisfactory results. The possible CL mechanism is also discussed briefly.

A fast, stability-indicating, and validated liquid chromatography method for the purity control of lercanidipine hydrochloride in tablet dosage form

A robust, sensitive, and stability-indicating rapid resolution liquid chromatography method for the simultaneous determination of process impurities and degradation products of lercanidipine hydrochloride in pharmaceutical dosage form was developed and validated. The chromatographic separation was performed on the Zorbax SB C18 [(50 × 4.6) mm] 1.8 μm column, using gradient elution of a potassium dihydrogen phosphate buffer (pH 3.5, 0.01 M) and acetonitrile. The flow rate was 1.0 ml/min and UV detection was performed at 220 nm. The method was further evaluated for its stability-indicating capability by hydrolytic, oxidative, thermal, thermal with moisture, and photolytic degradation studies. All acceptance criteria of the International Conference on Harmonization guidelines for validation were covered in the method validation. This method can be used for purity control during manufacture and real time stability studies. A shorter run time of 10 minutes and good solution stability for at least 48 hours allowed the quantification of more than 50 samples per day with comparatively lower costs than existing methods.

A Stability-indicating High Performance Liquid Chromatographic Assay for the Simultaneous Determination of Atenolol and Lercanidipine Hydrochloride in Tablets

A simple, rapid, precise and accurate isocratic reversed phase stability indicating HPLC method was developed and validated for the simultaneous determination of atenolol and lercanidipine hydrochloride in commercial tablets. The chromatographic separation was achieved on phenomenex Gemini C18 (250×4.6 mm, 5 μm) column using a mobile phase consisting of acetonitrile and buffer (20 mM potassium dihydrogen phosphate pH 3.5) in the ratio of (55:45, v/v) at a flow rate of 1.0 ml/min and UV detection at 235 nm. The linearity of the proposed method was investigated in the range of 40-160 μg/ml (r²=0.9995) for atenolol and 8-32 μg/ml (r²=0.9993) for lercanidipine. Degradation products produced as a result of stress studies did not interfere with the detection of atenolol and lercanidipine and the assay can thus be considered stability-indicating.

The solution, solid state stability and kinetic investigation in degradation studies of lercanidipine: study of excipients compatibility of lercanidipine

The objectives of this research were to evaluate the stability of lercanidipine in solution state and solid state and explore the compatibility of drug with oils, surfactants and cosurfactants as excipients. The effect of pH on the degradation in solution state was studied through pH-rate profile of lercanidipine in constant ionic strength buffer solutions in pH range 1-8 which gives the pH of maximum stability. Powdered lercanidipine was stored under 40°C/0%~75% relative humidities (RH) or 0% RH/5~50°C to study the influence of RH and temperature on the stability of lercanidipine in solid state. Binary mixtures of lercanidipine and different excipients were stored at 40°C/75% RH, 40°C and at room temperature for excipient compatibility evaluation. The degradation of lercanidipine at different pH appears to fit a typical first-order reaction, but in solid state, it does not fit any obvious reaction model. Moisture content and temperature both play important roles affecting the degradation rate. Lercanidipine exhibits good compatibility with surfactants, cosurfactants and oils as excipients under stressed conditions of different storage temperature in a 3-week screening study. Moreover, the proposed high-performance liquid chromatography method was utilized to investigate the kinetics of the acidic and alkaline degradation processes of lercanidipine at different temperatures.

Investigation on the photochemical stability of lercanidipine and its determination in tablets by HPLC–UV and LC–ESI–MS/MS

The photostability of lercanidipine, a dihydropyridine calcium-channel blocker used in the treatment of the hypertension, was studied. Drug substance and its solutions and formulations were exposed to UV-A radiations (solar simulator) and the photodegradation process was monitored by UV spectrophotometry, HPLC and HPLC-mass spectrometry. The effect of the solvent (ethanol and ethanol/PBS 1:1 v/v) on the photodegradation pathway and kinetic was evaluated. Lercanidipine and its photodegradation products were separated by a selective reversed-phase HPLC method and the main photoproducts were characterized by HPLC-MS/MS analysis, using an electrospray ionization source (ESI) and an ion trap analyzer. Photochemical reactions, involved in the photodegradation of lercanidipine, include aromatisation of the dihydropyridine moiety, formation of nitrosoderivatives and N-dealkylation in the side chain. The developed stability-indicating HPLC method was then applied to the quality control of commercially available lercanidipine formulations (tablets).

Ultra-performance liquid chromatography/tandem mass spectrometry method for the determination of lercanidipine in human plasma

A simple, sensitive and rapid ultra-performance liquid chromatography/positive electrospray ionization tandem mass spectrometry (UPLC/ESI-MS/MS) method has been developed and validated for the determination of lercanidipine in human plasma. Lercanidipine and the internal standard, nicardipine, were extracted from plasma by liquid-liquid extraction using tert-butyl methyl ether as the extraction solvent. UPLC analysis was performed isocratically on an AcQuity UPLC BEH C18 analytical column (2.1 x 50.0 mm i.d., particle size 1.7 microm). The mobile phase consisted of 70% acetonitrile in water containing 0.2% v/v formic acid and pumped at a flow rate of 0.30 mL/min. ESI in positive ion mode, with multiple reaction monitoring (MRM), was chosen for the detection of the analytes. The assay was linear over a concentration range of 0.05-30 ng/mL for lercanidipine with a limit of quantitation of 0.05 ng/mL. Quality control samples (0.05, 0.15, 15 and 25 ng/mL) in five replicates from five of analytical runs demonstrated intra-assay precision (% CV < or =7.3%), inter-assay precision (% CV < or =6.1%) and an overall accuracy (% relative error) of less than 6.2%. A run time of less than 1.0 min for each sample made it possible to analyze a large number of human plasma samples per day. The method can be used to quantify lercanidipine in human plasma covering a variety of pharmacokinetic or bioequivalence studies.