HPLC-UV method development and validation for the quantification of ropinirole in new PLGA multiparticulate systems: Microspheres and nanoparticles

Method development and validation for simultaneous determination of Eletriptan hydrobromide and Itopride hydrochloride from fast dissolving buccal films by using RP-HPLC

One of the most effective, rapid, and simple methods reversed-phase high-performance liquid chromatography (RP-HPLC) was used for simultaneous development and validation of Eletriptan hydrobromide (ELE HBR) and Itopride hydrochloride (ITP HCL) in combination. The method was validated based on the regulations of United States Pharmacopeia (USP) and International Conference on Harmonization (ICH) guidelines. Separation of both drugs was achieved within approximately 5 min by using a mobile phase made up of a 70:30 ratio of phosphate buffer and acetonitrile having a flow rate of 1 mL min−1. Furthermore, a comprehensive study was conducted on precision, accuracy, linearity, inter-day, intra-day studies, an assay of formulated films, and stability studies of combined prepared film. Co-efficient of correlation ranged between 0.9993, and 0.9965 for ELE HBR and ITP HCL respectively. The accuracy of the developed method was accurate as drug recoveries in both cases of ITP HCL, and ELE HBR falls between (99.87, 99.96, and 99.84%) to (99.81, 99.12, and 98.44%) respectively having a concentration range of solutions between 10, 30 and 50 μg mL−1 dilution. Films developed by using both drugs in combination were then validated for assay studies, and it was found that substantial results of 99.05%, and 99.87% were found in the case of ITP HCL and ELE HBR respectively. The stability of the solution and mobile phase showed the method's accuracy as the results were 97% for ITP HCL and 99% for ELE HBR. The proposed method developed for simultaneous determination of ITP HCL and ELE HBR was developed and validation and no interaction of any excipient were found.

Polyethylenimine/cGAMP Nanocomplexes for STING-Mediated Cancer Immunotherapy: Formulation and Characterization Using Orthogonal Techniques

Cyclic GMP-AMP (cGAMP) has lately been extensively investigated in cancer immunotherapy due its activation of the innate immunity stimulation of interferon genes (STING) pathway within antigen presenting cells (APC) leading to an increase in tumor specific CD8+ T cells. As negatively charged dinucleotides are prone to enzymatic degradation before being taken up by APC, there is a need for an appropriate carrier. Therefore, polyethylenimine (PEI), a gold standard for oligonucleotide delivery, was selected. Molecular weight, type of PEI and N/P ratio between PEI/cGAMP were investigated in terms of toxicity, efficacy and physicochemical properties of the nanocomplexes (NCs) such as size, zeta potential and shape. Due to lack of nano-medicine regulations and the need for a case-by case assessment, here we examine these parameters by several orthogonal methods, such as dynamic light scattering (DLS), nanoparticle tracking analysis (NTA) and online asymmetric flow field flow fractionation (AF4) connected to DLS. N/P ratio of 2/1 ratio using linear PEI 25 kDa resulted in larger, positively charged particles of elongated shape, which were shown to have the best toxicity/efficacy ratio among different PEIs and ratios tested.

Validation of a Rapid and Easy-to-Apply Method to Simultaneously Quantify Co-Loaded Dexamethasone and Melatonin PLGA Microspheres by HPLC-UV: Encapsulation Efficiency and In Vitro Release

This paper discusses the development and validation of a rapid method for the reversed phase HPLC-UV quantification of biodegradable poly(D,L-lactic-co-glycolic) acid (PLGA) microspheres co-loaded with two neuroprotective agents (dexamethasone and melatonin) (DX-MEL-MSs) to be intravitreally administered as a promising glaucoma treatment. The study was performed to validate two procedures that quantify the content of the two active substances entrapped into the polymer matrix during an encapsulation efficiency assay and the amount of drugs liberated over time during the in vitro release assay. The reversed-phase method allowed for the simultaneous determination of dexamethasone and melatonin, which were respectively detected at 240.5 and 222.7 nm. Chromatographic separation was performed using an Ascentis^® C18 HPLC Column (25 cm × 4.6 mm, 5 µm) with an isocratic mobile phase composed of methanol-water (70:30, v/v) with 1.0 mL min⁻¹ flow rate. The two procedures were validated analytically in terms of system suitability testing, specificity, linearity, precision, accuracy, sensitivity, and robustness. Both the validated procedures were applied to characterize DX-MEL-MSs and were found appropriate to quantify the drug quantities encapsulated and estimate their release profile over 10 days. The validation study designed in this work can be helpful for planning any other protocols that refer to the quantification of PLGA based drug delivery systems.

Ropinirole silver nanocomposite attenuates neurodegeneration in the transgenic Drosophila melanogaster model of Parkinson's disease

Parkinson's disease (PD) is a progressive neurodegenerative disease due to the degeneration of dopaminergic neurons in substantia nigra pars compacta of the mid brain. The present study investigates the neuro-protective role of synthesized ropinirole silver nanocomposite (RPAgNC) in Drosophila model of PD. α-synuclein accumulation in the brain of flies (PD flies) leads to the damage of dopaminergic neurons, dopamine depletion, impaired muscular coordination, memory decline and increase in oxidative stress. Ingestion of the RPAgNC by Drosophila significantly prevented the neuronal degeneration compared to only ropinirole. The results confirm that the RPAgNC exerts more neuro-protective effect compared to dopamine agonist i.e. ropinirole as such drug in experimental PD flies. This article is part of the special issue entitled 'The Quest for Disease-Modifying Therapies for Neurodegenerative Disorders'.

Development and validation of RP-HPLC method for simultaneous estimation of docetaxel and ritonavir in PLGA nanoparticles

OBJECTIVES

The main objective of the present study was to develop and validate simple, precise, sensitive and accurate RP-HPLC method for the simultaneous estimation of docetaxel (DTX) and ritonavir (RTV) in PLGA nanoparticles (PLGA-NPs).

METHODS

The DTX and RTV co-loaded PLGA-NPs were developed by the nanoprecipitation technique. The RP-HPLC method was developed by using (Agilent Compact LC-1220) and Zorbax Eclipse plus C18 column (150×4.6mm, 3.5μm, Agilent). Finally, the developed method was validated according to the international conference on harmonization (ICH) guidelines.

RESULTS

The chromatographic separations of DTX and RTV with good resolutions have been achieved by using the mobile phase Acetonitrile: Water (60:40 v/v) containing 0.1% v/v of orthophosphoric acid at a flow rate of 1.0mL/min, injection volume of 25μL, and at 239nm wavelengths. The validated method found to be linear in the range of 0.001-100μg/mL for DTX and RTV. Detection and quantification limits for DTX were found to be 0.7 and 2.31μg/mL respectively and for RTV it is 0.3 and 2.87μg/mL respectively. The % RSD was found to be less than 2% revealing the precision of the developed method. Besides, the recovery rate was observed close to 100% for both the drugs confirming the accuracy of the method. Minor alterations in the chromatographic conditions have revealed robustness and ruggedness of the developed method.

CONCLUSION

The developed analytical method is simple, precise, sensitive, and reproducible which can be used for the simultaneous estimation of DTX and RTV in the PLGA-NPs.

Developing an Improved UHPLC Method for Efficient Determination of European Pharmacopeia Process-Related Impurities in Ropinirole Hydrochloride Using Analytical Quality by Design Principles

This article presents the development of a reversed-phase ultra-high-performance liquid chromatographic method for determining process-related impurities in ropinirole hydrochloride drug substance applying the analytical quality by design approach. The current pharmacopeial method suffers from selectivity issues due to two coelutions of two pairs of impurities. The development of a new method began with preliminary experiments, based on which the Acquity UPLC BEH C8 was selected as the most appropriate column. The effects of six different critical method parameters (CMPs) were then investigated using a fractional factorial screening design. Column temperature, the ratio of methanol in mobile phase B, and gradient slope turned out to be highly significant CMPs in achieving critical resolutions, and they were further evaluated using a central composite face-centered response-surface design. Mathematical models were created by applying a multiple linear regression method. Based on the elution order of an unknown degradation impurity and impurity C, two design spaces were established, and for each design space an optimal combination of CMPs was determined. The method developed was validated for precision, accuracy, linearity, and sensitivity, and it was proven suitable for determining nine process-related impurities of ropinirole.

Neuroprotective Effect of Ropinirole Lipid Nanoparticles Enriched Hydrogel for Parkinson's Disease: In Vitro, Ex Vivo, Pharmacokinetic and Pharmacodynamic Evaluation

Parkinson’s disease (rp) is a progressive neurodegenerative disorder. Ropinirole (RP) is a newer generation dopamine agonist used for the treatment of PD. It is prescribed as oral dosage form. However, limited oral bioavailability and frequent dosing limits the RP usage. The objective of the current investigation was to develop, optimize, evaluate pharmacokinetic (PK) and pharmacodynamic (PCD) activity of RP loaded solid lipid nanoparticles (RP-SLNs) and nanostructured lipid carriers (RP-NLCs) and containing hydrogel (RP-SLN-C and RP-NLC-C) formulations for improved oral and topical delivery. RP loaded lipid nanoparticles were optimized and converted to hydrogel using carbopol 934 as the gelling polymer. PK and PCD studies in haloperidol-induced PD were conducted in male Wistar rats. In vitro and ex vivo permeation studies showed sustained release profile and enhanced permeation compared with control formulations. Differential scanning calorimeter and X-ray diffraction studies revealed amorphous transformation; scanning electron microscope showed the spherical shape of RP in lipid nanoparticles. PK studies showed 2.1 and 2.7-folds enhancement from RP-SLN and RP-NLC from oral administration, 3.0 and 3.3-folds enhancement from RP-SLN-C and RP-NLC-C topical administration, compared with control formulations, respectively. RP-SLN-C and RP-NLC-C showed 1.4 and 1.2-folds topical bioavailability enhancement compared with RP-SLN and RP-NLC oral administration, respectively. PCD studies showed enhanced dopamine, glutathione, catalase levels and reduced lipid peroxidation levels, compared with the haloperidol-induced PD model. Overall, the results demonstrated that lipid nanoparticles and corresponding hydrogel formulations can be considered as an alternative delivery approach for the improved oral and topical delivery of RP for the effective treatment of PD.

Degradation kinetics study of 1-palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol (PLAG) by a validated stability-indicating RP-HPLC method

The chemical stability of 1-palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol (PLAG), a therapeutic agent for neutropenia, was investigated using a validated stability-indicating reversed phase high-performance liquid chromatographic (RP-HPLC) method. The forced degradation of PLAG was carried out under the stress conditions of hydrolysis (alkaline, acidic and various pH buffers), oxidation, photolysis and heat. A simple, sensitive, specific, robust, precise and accurate RP-HPLC method was developed and validated for evaluating the degradation kinetics of PLAG. The chromatographic validation of various parameters, such as system suitability, detection limit, quantification limit, linearity, accuracy, precision, specificity, robustness and stability, was achieved. The method was validated for linearity, accuracy and precision over the concentration range of 0.7813-100μg/mL (r²=0.9999). The proposed method provided excellent stability study of PLAG indicated by the resolution of degradation products from the drug. Degradation of PLAG provided first order kinetics under all experimental conditions. PLAG was catalysed more rapidly in alkaline and acidic conditions than in neutral conditions. PLAG was relatively stable in photolytic and oxidative conditions compared to hydrolysis and thermal conditions, although this drug was not also stable in these conditions. Exposed to high temperature, PLAG was more rapidly catalysed. The activation energy evaluated from the Arrhenius plot was about 110kJ/mol in the thermal conditions. Additionally, PLAG with a t_1/2 of about 400h was very stable at room temperature. Therefore, PLAG was considerably influenced by alkaline and acidic hydrolysis, and thermal degradation.

Nanotechnology-based drug delivery of ropinirole for Parkinson's disease

A new drug delivery system is developed for ropinirole (RP) for the treatment of Parkinson's disease (PD) consisting of biodegradable poly (D,L-lactide-co-glycolide) (PLGA) nanoparticles (NPs). The formulation selected was prepared with 8 mg RP and 50 mg PLGA 502. This formulation exhibited mean encapsulation efficiency of 74.8 ± 8.2%, mean particle size lower than 155 nm, the zeta potential of -14.25 ± 0.43 mV and zero-order in vitro release of RP (14.13 ± 0.17 μg/h/10 mg NPs) for 5 d. Daily doses of the neurotoxin rotenone (2 mg/kg) given i.p. to male Wistar rats induced neuronal and behavioral changes similar to those of PD. Once neurodegeneration was established (15 d) animals received RP in saline (1 mg/kg/d for 35 d) or encapsulated within PLGA NPs (amount of NPs equivalent to 1 mg/kg/d RP every 3 d for 35 d). Brain histology and immunochemistry (Nissl-staining, glial fibrillary acidic protein and tyrosine hydroxylase immunohistochemistry) and behavioral testing (catalepsy, akinesia, rotarod and swim test) showed that RP-loaded PLGA NPs were able to revert PD-like symptoms of neurodegeneration in the animal model assayed.