Nanocrystals of Mangiferin Using Design Expert: Preparation, Characterization, and Pharmacokinetic Evaluation.

Making nanoscale drug carriers could boost the bioavailability of medications that are slightly water soluble. One of the most promising approaches for enhancing the chemical stability and bioavailability of a variety of therapeutic medicines is liquid nanocrystal technology. This study aimed to prepare nanocrystals of mangiferin for sustained drug delivery and enhance the pharmacokinetic profile of the drug. The fractional factorial design (FFD) was used via a selection of independent and dependent variables. The selected factors were the concentration of mangiferin (A), hydroxypropyl methyl cellulose (HPMC) (B), pluronic acid (C), tween 80 (D), and the ratio of antisolvent to solvent (E). The selected responses were the particle size, polydispersity index (PDI), zeta potential, and entrapment efficiency. The nanocrystals were further evaluated for mangiferin release, release kinetics, Fourier transforms infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), X-ray diffraction (XRD), particle size, zeta potential, and scanning electron microscopy (SEM). The stability studies of developed nanocrystals were performed for 6 months and pharmacokinetics on albino rabbits. The value of entrapment efficiencies ranged from 23.98% to 86.23%. The percentage release of mangiferin varied from 62.45 to 99.02%. FTIR and DSC studies showed the stability of mangiferin in the nanocrystals. The particle size of the optimized formulation was almost 100 nm and -12 mV the value of the zeta potential. The results of stability studies showed that the nanocrystals of mangiferin were stable for a period of six months. The peak plasma concentration of mangiferin from nanocrystals and suspension of mangiferin were 412 and 367 ng/mL, respectively. The value of AUC0-t of nanocrystals and suspension of mangiferin was 23,567.45 ± 10.876 and 18,976.12 ± 9.765 µg×h/mL, respectively, indicating that the nanocrystals of mangiferin showed greater availability of mangiferin compared to the suspension of the formulation. The developed nanocrystals showed a good release pattern of mangiferin, better stability studies, and enhanced the pharmacokinetics of the drug.

A Hematological and Histopathological Study on Diphenhydramine Nasal Nano-gel and Nano-emulgel for the Management of Allergic Rhinitis in Animal Model.

The study aims to determine histamine efficacy on hematologic values in experimental animal model, under physiological and pathological conditions after inducing diphenhydramine-formulated nasal nano-gel/nano-emulgel in comparison with conventional nasal spray regime. In this study, we conducted experiment on New Zealand white male rabbits to prove our hypothesis that nasal diphenhydramine nano-gel and nano-emulgel can penetrate the nasal mucosa faster to show drug response and subside histaminic symptoms than market nasal spray (as reference). Blood samples from 48 New Zealand white male rabbits, under both experimental conditions (physiological and pathological) divided into four groups for each (n = 6) were investigated after inducing each dosage form intranasally. Hematologic parameters (WBCs, RBCs, HGB, PLTs, lymphocytes, monocytes, eosinophils, granulocyte counts) were analyzed in whole blood samples, collected at different time intervals. ANOVA and completely randomized design (CRD) were applied for statistical analysis. Histopathologically, nasal tissues of all groups were analyzed to see intramucosal surface changes. Data of descriptive statistics of hematological parameters analyzed at confidence level 95% showed that under physiological condition, hematological parameters of all groups were lying in normal range, whereas under pathological condition, low values of all hematological parameters were observed in all groups due to allergenic condition. The groups B (allergenic rabbits treated with formulated diphenhydramine nasal nano-gel) and C (allergenic rabbits treated with formulated diphenhydramine nasal nano-emulgel) have shown good changes in the treatment of allergenic rabbits as compared to group D (allergenic rabbits treated with formulated diphenhydramine nasal spray). The completely randomized ANOVA and Tukey HSD all-pairwise comparison tests of hematological parameters were applied that showed all groups in both studies were significantly different from each other. It was observed after histopathological study of nasal membrane tissues that change in mucosa has occurred due to the passage of drug. In summary, hematological profile and histopathological study have demonstrated the comparable results with conventional diphenhydramine nasal spray and formulated diphenhydramine nasal nano-gel/nano-emulgel which can exhibit considerable drug delivery dosage forms in the management of allergic rhinitis in animal model.

Formulation Development and Evaluation of Diphenhydramine Nasal Nano-Emulgel.

The aim of present study is to formulate diphenhydramine nasal nano-emulgels, having lipophilic nano-sized interior droplets, with better penetration for targeted controlled delivery to mucous membrane. Different diphenhydramine (DPH) nasal nano-emulgels were developed having propylene glycol and olive oil (as permeation enhancers) by using RSM for optimization and then evaluated for physico-chemical characteristics and thermal stability. In-vitro drug release through cellophane membrane was conducted and results were analyzed statistically. Further, gelation, mucoadhesive stress, and ex-vivo and histopathological studies were performed on optimized formulation by using goat nasal membrane. Among all formulations, E2 showed maximum DPH release at higher concentration olive oil (4%) and lower concentration propylene glycol (PG) (25%) within 4 h. All formulations have followed first-order kinetics and drug release mechanism was Fickian diffusion. Analysis of variance (ANOVA) and multiple linear regression analysis (MLRA) were used to compare results among formulations and 3D surface plots were constructed also. Optimized formulation showed immediate prolong gelation in artificial nasal mucosa and excellent mucoadhesive property (72.5 ± 1.5 dynes/cm2). Approximately 97.1% optimized formulation was permeated through membrane within 4 h, having a high flux rate (33.19 ± 0.897 µg/cm2/min) with diffusion coefficient (0.000786 ± 4.56 × 10-5 cm2/min) while drug contents remained on mucosal membrane for 24 h. Histopathologically, change on intra-mucosal surface of excised membrane was observed due to passage of drug through it. In summary, combination of PG and olive oil in nasal DPH nano-emulgel can be utilized successfully for targeted controlled delivery. The optimized formulation has excellent permeability and prolonged residence time on mucosal surface, which prove its good anti-histaminic activity in case of allergic rhinitis.

MICROWAVE RADIATION INDUCED SYNTHESIS OF HYDROXYPROPYL METHYLCELLULOSE-GRAFT- (POLYVINYLALCOHAL-CO-ACRYLIC ACID) POLYMERIC NETWORK AND ITS IN VITRO EVALUATION.

A microwave induced irradiation synthesis, was proposed for the preparation of hydroxypropyl methylcellulose-graft-(polyvinylalcohal-co-acrylic acid) hydrogels. The hydrogels were separately synthesized by using microwave irradiation method and conventional water bath heating method. Moreover, the prepared hydrogels were loaded with an antihypertensive drug, captopril. Chemical groups, thermal stability and surface morphology of these hydrogels were characterized by FT-IR, DSC and SEM. Swelling ratios of the gels were measured gravimetrically at'pH 1.2 and 7.4. Results showed that micrographs obtained from scanning electron microscopy (SEM), revealed that gels synthesized using microwave irradiation had more uniformly porous network structures. The uniformity in porosity was due to rapid and instantaneous penetration of microwave energy throughout the surface and they had higher swelling ratios in comparison to hydrogels synthesized by water bath method. Thermal analysis (DCS and TGA) depicted that crosslinked polymers were more stable. FT-IR analysis had confirmed the formation of the new polymeric network. X-ray diffractogram revealed that crystallinity of HPMC was reduced in hydrogel prepared by microwave radiation. It had also been observed that high crosslinking density diminish swelling of hydrogel. A stable network of hydroxypropyl methylcellulose (HPMC), poly(vinylalcohal) (PVA) and acrylic acid was developed in shorter time period under influence of microwave radiations.

Formulation, Evaluation and release rate characteristics of medicated jelly of vitamin C.

Medicated jelly formulations are patient friendly dosage form for pediatric, geriatric and dysphagic patients. These formulations offer rapid dissolution and absorption of drugs through oral mucosa therefore show the early onset of action. The objective of the study was to develop and evaluate oral jelly formulations of vitamin C. Slurry method was adopted using glucose 103gm, sugar 67gm, gelatin 10gm and sorbitol 6.56gm. Preformulation studies were performed including the organoleptic profile, pH, and solubility of both drugs. The medicated jelly of Vitamin C was prepared and evaluated for physical characteristics, weight variation, syneresis, pH, taste and palatability, drug content, release rate characteristics and stability studies. All the jellies were found to have patient welcoming taste and were palatable. All formulations showed more than 50% drug release within 15 minutes, while 93% drug was released in 30 minutes. The results of release kinetics showed that the formulation followed the zero order release kinetics. Thus the drug was released at constant rate independent of the drug concentration involved in the process. All the medicated jellies were found to remain stable stored for 60 days at different temperatures. The present study revealed that medicated jellies of vitamin C could be employed orally in an effective form as an alternative solid oral dosage form for special population such as pediatrics, geriatrics and patients with dysphagia.

DEVELOPMENT AND CHARACTERIZATION OF SMART DRUG DELIVERY SYSTEM.

Present work concerned with development and evaluation of an innovative drug carrier, as smart drug delivery system for highly acid labile drug. Free radical polymerization technique was employed to develop pH sensitive drug delivery system by using carboxymethyl cellulose (polymer), methacrylic acid (monomer), potassium persulfate (initiator) and N,N methylene bisacrylamide (crosslinker). Prepared crosslinked polymer was characterized by swelling analysis at acidic and basic pH to evaluate pH responsive swelling, instrumental analysis (SEM, FIIR and thermal analysis) and pH responsive release of model drug rabeprazole sodium. Characterization of smart drug delivery concluded that pH responsive swelling and drug release parameters were directly related with methacrylic acid concentration in the crosslinked polymer. It was observed that by raising methacrylic acid contents swelling at basic pH enhanced and crosslinker contents increment reduce swelling. Among nine formulations with varying formulation contents, CMA2 exhibited more pH sensitive swelling and cumulative drug release at alkaline pH. Results of investigation recommended that CMA2 can be a best crosslinked polymer as smart drug carrier.

Rutin-Nickel Complex: Synthesis, Characterization, Antioxidant, DNA Binding, and DNA Cleavage Activities.

The rutin-nickel (II) complex (RN) was synthesized and characterized by elemental analysis, UV-visible spectroscopy, IR, mass spectrometry, 1H NMR, TG-DSC, SEM, and molar conductivity. The low molar conductivity value investigates the non-electrolyte nature of the complex. The elemental analysis and other physical and spectroscopic methods reveal the 1:2 stoichiometric ratio (metal/ligand) of the complex. An antioxidant study of rutin and its metal complex against DPPH radical showed that the complex has more radical scavenging activity than free rutin. The interaction of complex RN with DNA was determined using fluorescence spectra and agarose gel electrophoresis. The results showed that RN can intercalate moderately with DNA, quench a strong intercalator ethidium bromide (EB), and compete for the intercalative binding sites. The complex showed significant cleavage of pBR 322 DNA from supercoiled form (SC) to nicked circular form (NC), and these cleavage effects were dose-dependent. Moreover, the mechanism of DNA cleavage indicated that it was a hydrolytic cleavage pathway. These results revealed the potential nuclease activity of the complex to cleave DNA.

Polymer blend: a new approach for eliminating curing effect of aqueous dispersion coatings

The aim of present work was to investigate blends of Eudragit® NE 30D with Aquacoat® ECD using different ratios to eliminate curing effect associated with individual polymers. Propranolol HCl 10% w/w was layered onto sugar cores using 5% w/w HPMC as a binder. Drug-layered-cores were coated either with pure or blends of Aquacoat® ECD: Eudragit® NE 30D in a fluidized bed coater to obtain 20% w/w coating level. Talc 35% w/w was used as anti-tacking agent. The pellets were characterized for in vitro dissolution studies, morphology, water uptake-weight loss, osmolality and adhesion of coating after curing at 60 °C or 60 °C/75% RH for 24 h. The findings revealed that Aquacoat® ECD coated pellets showed curing effect due to further gradual coalescence of polymeric particles which resulted into better film formation upon curing. In contrast, the curing effect of Eudragit® NE 30D coated pellets was caused by decrease in adhesion of coatings after curing which provided entirely different swelling behavior of uncured (localized swelling) and cured (uniform swelling) pellets. The undesired curing effect of individual polymers was eliminated by using their blends in appropriate ratio.