Smart nanocrystal of indomethacin: Nanonization and characterization through top down method of media milling.

Indomethacin is potent and effective drug belongs to NSAID group having low bioavailability. To address this issue the novel method is Nanosuspensions which can be achieved through bottom up and top down methods. The drug concentration, batch size and crystallinity retention are the problems associated with bottom up method consequently top down method was applied. In current project batch size of 350 ml was prepared by mixing 3.5% of Indomethacin with polymer solution. Then it was introduced into Dena⌖ having 0.2µm yttrium reinforced zirconium beads. The effect of milling time was observed for sixty minutes. Stable nanocrystals with particle size of 161nm ±1.90 with PDI of 0.229 ±0.06 were produced. The DSC and PXRD confirmed the crystallinity of created nanocrystals. The pattern of particle size reduction was initially abrupt and then gradual. The two months Stability studies at 4°C and at 25°C revealed that polymers combination (PVP-K30, HPMC-6cps, SDS) were effective in marinating the stability. The SEM and TEM studies unfastened that nanocrystals were homogenously distributed with discrete crystalline morphology. The fabricated nanocrystals demonstrated marked dissolution rate compared to the raw and marketed formulations. It is demonstrated that it is useful for industry due to high drug concentration, large batch size and retention of distinct characteristics.

Enhanced dissolution rate of Ketoprofen by fabricating into smart nanocrystals.

The low bioavailability of Ketoprofen is associated with its hydrophobic nature that can be solved by nanonization. For this purpose, a polymeric solution with drug concentration of 3.5% w/w was formulated. The produced solution was milled for 60 minutes in DENA® mill which contains 0.2µ m yttrium reinforced zirconium beads. The Physicochemical properties, characterization including stability studies of the prepared nanoparticles were carried out using pharmacopeial techniques of zeta potential, PXRD, DSC, SEM and TEM. Results suggest that stable crystalline nanocrystals with a size of 169±1.98nm with PDI of 0.194±0.04 and zeta potential of -22.0±2.25mV were produced. Moreover, enhances in-vitro release rate of 78.6% for the processed Ketoprofen was achieved in first 5 min as compared to raw form and marketed drug which released only 22.9% and 33.1% of drug respectively. The 60 days stability studies at 4oC & 25°C revealed that polymers PVP-K30-HPMC-6cps-SDS were effective in stabilizing the nanocrystals. Comparatively stable ketoprofen nanocrystals were successfully produced by DENA® mill with marked enhanced dissolution rate. It proved a useful for commercialization technique due to high drug concentration and retention of distinct characteristics at large scale.

COLOCASIA ESCULENTA CORMS MUCILAGE-ALGINATE MICROSPHERES OF OXCARBAZEPINE: DESIGN, OPTIMIZATION AND EVALUATION.

The present investigation was undertaken with an objective of formulating sustained release microspheres of oxcarbazepine (OXC), an anti-epileptic drug, to overcome poor patient compliance and exposure to high doses associated with currently marketed OXC dosage forms. Ionic gelation technique was used to prepare OXC microspheres by using sodium alginate along with rate controlling polymer Colocasia esculenta mucilage (CEM) matrix as well coated form. The microspheres have been characterized by differential scanning calorimetry (DSC) for understanding thermal stability and Fourier transform infrared (FT-IR) spectroscopy to investigate the chemical interaction as well as to assess the structure of drug-loaded formulation. Surface morphology of the microspheres was investigated by scanning electron microscope (SEM). The size distribution of OXC microspheres as studied by optical microscopy was in the range of 394-575 pm. The microspheres exhibited encapsulating efficiency from 75 to 92%. The release of drug from the microspheres at pH 1.2 is negligible. Under neutral conditions, the microspheres were swell and release was attributed mainly to polymer relaxation. The release pattern from microspheres followed Korsmeyer-Peppas model and the value of n > 1 showed that drug released by anomalous (non-Fickian) diffusion. The data obtained thus suggest that a microparticulate system can be successfully designed by using CEM with alginate for sustained delivery of OXC.

APPLICATION OF VARIOUS POLYMERS AND POLYMERS BASED TECHNIQUES USED TO IMPROVE SOLUBILITY OF POORLY WATER SOLUBLE DRUGS: A REVIEW.

Solubility is concerned with solute and solvent to form a homogenous mixture. If solubility of a drug is low, then usually it is difficult to achieve desired therapeutic level of drug. Most of the newly developed entities have solubility problems and encounter difficulty in dissolution. Basic aim of solubility enhancement is to achieve desired therapeutic'level of drug to produce required pharmacological response. Different techniques are being used to enhance the solubility of water insoluble drugs. These techniques include particle size reduction, spray drying, kneading method, solvent evaporation method, salt formation, microemulsions, co-solven- cy, hydrosols, prodrug approach, supercritical fluid process, hydrogel micro particles etc. Selection of solubility improving method depends on drug properties, site of absorption, and required dosage form characteristics. Variety of polymers are also used to enhance solubility of these drugs like polyethylene glycol 300, polyvinyl pyrrolidone, chitosan, ß-cyclodextrins etc.

Formulation and in vitro evaluation of nateglinide microspheres using HPMC and carbopol-940 polymers by ionic gelation method.

This study involves the design and characterization of Nateglinide (NAT) microspheres to enhance patient compliance. Ionic gelation technique was used to prepare Nateglinide Microspheres by using rate controlling polymers Carbopol-940 and Hydroxypropylmethyl cellulose (HPMC). Shape and surface were evaluated with Scanning electron microscopy (SEM). Percentage Yield, Particle size analysis, Encapsulating Efficiency, Micromeritic analysis, Fourier Transform Infra-Red Spectroscopy (FTIR), Differential Scanning Colorimetry (DSC) were done for characterization of Microspheres. Drug release studies were performed at pH 1.2 and 7.2 using USP dissolution type-II apparatus and release rates were analyzed by the application of different pharmacokinetic models. The size of microspheres was found to be varied from 781µm to 853µm. Rheological studies proved excellent flow behavior while percentage yield was found to be varied from 72% to 79%. Absence of drug-polymers interactions was confirmed from FTIR and DSC results. The microspheres prepared with sodium alginate showed cracks while microspheres obtained from blend of Carbopol-940 plus sodium alginate were smooth and spherical. Maximum entrapment efficiency (71.4%) was achieved for Microspheres with Carbopol-940. The greater retardation in drug release was observed for microspheres containing Carbopol-940 and release pattern followed Higuchi kinetics model and negligible drug release was observed at pH 1.2.

Taro-corms mucilage-alginate microspheres for the sustained release of pregabalin: In vitro &in vivo evaluation.

Taro corms mucilage (TCM)-alginate microspheres had been prepared using TCM and alginate as blend and coated form in various ratios through inotropic gelation approach. The prepared microspheres have been of sphere-formed having coarse surface with average particle size within the range 498 µm ±â€¯0.17 to 715 µm ±â€¯0.34. The drug entrapment efficiency was 74.33 ±â€¯0.04% to 89.63 ±â€¯0.01% and swelling of microspheres followed the pattern (blended >coated >plain). FTIR research showed that there had been no interactions among pregabalin and polymers used; these microspheres were further characterized by DSC and XRD. The in vitro drug release followed sustained release (Korsmeyer-Peppas model) pattern (R2 = 0.9552-0.9906) and value of n > 1 showed that drug released by means of anomalous (non-Fickian) diffusion. The in vivo research established that there were highly significant difference with p < 0.001 within the pharmacokinetic parameters (Cmax, t½, AUC0-∞, Ke), while pregabalin microspheres in comparison to pure drug. Therefore, it is concluded that blended microspheres has greater bioavailability for pregabalin with sustained release effect. This evolved that TCM has been proved to be emerging potential pharmaceutical excipient for sustained release drug delivery systems.

Utilization of green formulation technique and efficacy estimation on cell line studies for dual anticancer drug therapy with niosomes.

The aim of the present study was to prepare niosome formulations for the simultaneous encapsulation, dual drug therapy, of two anticancer drugs by the ecological probe sonication method. Poloxamer and sorbitan monostearate were used as surface active agents in niosomes, and the water soluble doxorubicin and poorly-water soluble paclitaxel were used as anticancer drugs. Thorough physicochemical analysis were performed for the niosomes, and their cytotoxicity and activity were evaluated on MCF-7 and PC3-MM2 cancer cell lines. Prepared niosomes were small in size with sizes ranging from 137 nm to 893 nm, and entrapment efficiencies were high, ranging from 91.24% to 99.99%. During the four weeks stability testing, the particle size remained stable. The niosomal formulations showed in vitro sustained drug release profiles for doxorubicin and clearly increased the dissolution rate of poorly water soluble paclitaxel. The incorporation of both the drugs into niosomes improved cell penetration and antiproliferative activity of the drugs PC3-MM2 cell lines. As a conclusion, doxorubicin and paclitaxel loaded niosome formulations resulted in relatively stable, small sized niosomes with improved drug release profiles, low toxicity, better cell penetration and antiproliferative activity. The niosomes showed synergistic effect due to the presence of both drugs, which can overcome multidrug resistance.

Fabrication and characterization of dexibuprofen nanocrystals using microchannel fluidic rector.

PURPOSE: Dexibuprofen is an enantiomer of ibuprofen with low bioavailability which results from its hydrophobic nature. Nanosuspensions have developed a podium to solve the in vitro dissolution problem that frequently occurs in current research. MATERIALS AND METHODS: The drug and polymer solutions were mixed in a microchannel fluid reactor and the successive embryonic nanosuspension was decanted into a vial having the polymer solution. The impact of different process and formulation parameters including inlet angle, antisolvent and solvent flow rate(s), mixing time, drug concentration, polymer type and concentration was evaluated. RESULTS AND DISCUSSION: Stable dexibuprofen nanocrystals with a particle size of 45±3.0 nm and polydispersity index of 0.19±0.06 were obtained. Differential scanning calorimetry and powder X-ray diffraction confirmed the crystallinity. The key parameters observed were inlet angle 10°, antisolvent to solvent volume of 2.0/0.5 mL/min, 60 minutes mixing with 5 minutes sonication, Poloxamer-407 with a concentration of 0.5% w/v and drug concentration (5 mg/mm). The 60-day stability studies revealed that the nanocrystals were stable at 4°C and 25°C. The scanning electron microscopy and transmission electron microscopy images showed crystalline morphology with a homogeneous distribution. CONCLUSION: Stable dexibuprofen nanocrystals with retentive distinctive characteristics and having marked dissolution rate compared to raw and marketed formulations were efficiently fabricated. In future perspectives, these nanocrystals could be converted to solid dosage form and the process can be industrialized by chemical engineering approach.

Polymeric microspheres of okra mucilage and alginate for the controlled release of oxcarbazepine: In vitro &in vivo evaluation.

Oxcarbazepine-loaded alginate/okra pods mucilage microspheres were prepared through inotropic gelation technique for the sustained release of oxcarbazepine. The drug encapsulating efficiency of these microspheres was found 76.22 ±â€¯0.01% to 90.57 ±â€¯0.02% and their average particle sizes were 496 µm ±â€¯0.41 to 692 µm ±â€¯0.22. These microspheres were characterized in terms of swelling capacity, FTIR, DSC and SEM analysis. The in vitro drug release from these microspheres was followed sustained release (Korsemeyer - Peppas model) pattern (R2 = 0.9552-0.9906) and value of n > 1 showed that drug released by anomalous (non-Fickian) diffusion. The in vivo studies showed that there were highly significant difference with p < 0.001 in the pharmacokinetic parameters (Cmax, t½, AUC0-∞, Ke), when oxcarbazepine was formulated in form of polymeric microspheres as compared to pure drug.

Liposomal co-delivered oleanolic acid attenuates doxorubicin-induced multi-organ toxicity in hepatocellular carcinoma.

Doxorubicin in combination with other cytotoxic drugs has clinical advantages. However, doxorubicin-induced cardiotoxicity negatively impacts clinical utility and outcomes. Cardiotoxicity can result from increased oxidative stress or from a local cytochrome P450 mediated increase in 20-hydroxy-5, 8, 11, 14-eicosatetraenoic acid (20-HETE). Oleanolic acid (OA) is a natural pentacyclic triterpenoid with free radical scavenging, cardioprotective, and P450-mediated cyclooxygenase-upregulating properties. We investigated co-delivery of liposomal OA and doxorubicin in a HepG2 model of hepatocellular carcinoma (HCC). OA attenuated the cardiotoxicity induced by doxorubicin without compromising its anticancer activity. Apoptosis assays revealed that co-delivery of DOX and OA produced a synergistic anticancer effect. However, the drugs had antagonistic effects on cardiomyocytes. Female BALB/c nude mice treated with OA- and DOX-loaded liposomes (ODLs) exhibited reduced tumor growth, stable body weight, and stable organ indices. Reduced 20-HETE production suggested ODLs had limited cardiotoxicity. No changes in biochemical or histopathological markers were observed in mice treated with ODLs. Tailored co-delivery of OA and DOX may thus be an effective therapeutic strategy for treating HCC.

Linseed hydrogel-mediated green synthesis of silver nanoparticles for antimicrobial and wound-dressing applications.

Polysaccharides are being extensively employed for the synthesis of silver nanoparticles (Ag NPs) having diverse morphology and applications. Herein, we present a novel and green synthesis of Ag NPs without using any physical reaction conditions. Linseed hydrogel (LSH) was used as a template to reduce Ag+ to Ag0. AgNO3 (10, 20, and 30 mmol) solutions were mixed with LSH suspension in deionized water and exposed to diffused sunlight. Reaction was monitored by noting the change in the color of reaction mixture up to 10 h. Ag NPs showed characteristic ultraviolet-visible (UV/Vis) absorptions from 410 to 437 nm in the case of sunlight and 397-410 nm in the case of temperature study. Transmission electron microscopy images revealed the formation of spherical Ag NPs in the range of 10-35 nm. Face-centered cubic array of Ag NPs was confirmed by characteristic diffraction peaks in powder X-ray diffraction spectrum. Ag NPs were stored in LSH thin films, and UV/Vis spectra recorded after 6 months indicated that Ag NPs retained their texture over the storage period. Significant antimicrobial activity was observed when microbial cultures (bacteria and fungi) were exposed to the synthesized Ag NPs. Wound-healing studies revealed that Ag NP-impregnated LSH thin films could have potential applications as an antimicrobial dressing in wound management procedures.

Acute toxicity study of a polysaccharide based hydrogel from linseed for potential use in drug delivery system

ABSTRACT Linseed hydrogel (LSH) was evaluated by acute toxicity for its potential application in oral drug delivery design. White albino mice and rabbits were divided in four groups (I-IV) and different doses of LSH (1, 2 and 5 g/kg body weight) were given except to the control group (I) that was left untreated. Rabbits were monitored for eye irritation, acute dermal toxicity and primary dermal irritation, whereas, body weight, food and water consumption, hematology and clinical biochemistry, gross necropsy and histopathology of vital organs were scrutinized in mice. LSH was considered safe after eye irritation test as no adverse signs or symptoms were seen in the eye. In dermal toxicity and irritation study, skin of treated rabbits was found normal in color without any edema or erythema. After oral administration, there was no sign of any abnormalities in treated group animals (II-IV). The hematology and clinical biochemistry of treated group animals was comparable with the control group. Histopathology of vital organs has not shown any lesion or abnormalities. In the light of these outcomes, it can be concluded that LSH is not a hazardous biomaterial and could be incorporated as an excipient in oral and dermal preparations.

Green synthesis and characterization of polymer-stabilized silver nanoparticles.

Silver nanoparticles (Ag-NPs) were synthesized using a facile green chemistry synthetic route. The reaction occurred at ambient temperature with four reducing agents introduced to obtain nanoscale Ag-NPs. The variables of the green synthetic route, such as acidity, concentration of starting materials, and molar ratio of reactants were optimized. Dispersing agents were employed to prevent Ag-NPs from aggregating. Advanced instrumentation techniques, such as X-ray powder diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible spectroscopy (UV-vis), and phase analysis light scattering technique (ZetaPALS) were applied to characterize the morphology, particle size distribution, elemental composition, and electrokinetic behavior of the Ag-NPs. UV-vis spectra detected the characteristic plasmon at approximately 395-410 nm; and XRD results were indicative of face-centered cubic phase structure of Ag. These particles were found to be monodispersed and highly crystalline, displaying near-spherical appearance, with average particle size of 10.2 nm using citrate or 13.7 nm using ascorbic acid as reductants from particle size analysis by ZetaPALS, respectively. The rapid electrokinetic behavior of the Ag was evaluated using zetapotential (from -40 to -42 mV), which was highly dependant on nanoparticle acidity and particle size. The current research opens a new avenue for the green fabrication of nanomaterials (including variables optimization and aggregation prevention), and functionalization in the field of nanocatalysis, disinfection, and electronics.