In-vivo Pharmacokinetic Study Research Articles

Oral bioavailability enhancement of raloxifene by developing microemulsion using D-optimal mixture design: optimization and in-vivo pharmacokinetic study

The objective of this work was to utilize a potential of microemulsion for the improvement in oral bioavailability of raloxifene hydrochloride, a BCS class-II drug with 2% bioavailability. Drug-loaded microemulsion was prepared by water titration method using Capmul MCM C8, Tween 20, and Polyethylene glycol 400 as oil, surfactant, and co-surfactant respectively. The pseudo-ternary phase diagram was constructed between oil and surfactants mixture to obtain appropriate components and their concentration ranges that result in large existence area of microemulsion. D-optimal mixture design was utilized as a statistical tool for optimization of microemulsion considering oil, Smix, and water as independent variables with percentage transmittance and globule size as dependent variables. The optimized formulation showed 100 ± 0.1% transmittance and 17.85 ± 2.78 nm globule size which was identically equal with the predicted values of dependent variables given by the design expert software. The optimized microemulsion showed pronounced enhancement in release rate compared to plain drug suspension following diffusion controlled release mechanism by the Higuchi model. The formulation showed zeta potential of value −5.88 ± 1.14 mV that imparts good stability to drug loaded microemulsion dispersion. Surface morphology study with transmission electron microscope showed discrete spherical nano sized globules with smooth surface. In-vivo pharmacokinetic study of optimized microemulsion formulation in Wistar rats showed 4.29-fold enhancements in bioavailability. Stability study showed adequate results for various parameters checked up to six months. These results reveal the potential of microemulsion for significant improvement in oral bioavailability of poorly soluble raloxifene hydrochloride.

Brain Targeting of 1,9-Pyrazoloanthrone an c-Jun-N-terminal Kinase Inhibitor Using Liposomes for Effective Management of Parkinson's Disease.

The major challenge to treat Parkinson's disease (PD) is penetration of target molecule into the brain to improve the efficacy of drugs. To achieve better brain penetration and targeted delivery, 1,9-Pyrazoloanthrone (1,9-P) loaded liposomes were developed by solvent injection technique using ultrasonication and evaluated for particle size, morphology, entrapment efficiency, FT-IR, and in-vitro drug release studies. The potential of 1,9-Pyrazoloanthrone (1,9-P), a c-Jun-N-terminal Kinase (JNK-3) inhibitor which could stop or retard the rate of apoptosis of neuronal cells was also evaluated. In-vivo pharmacokinetic and brain uptake studies of liposomes were performed to investigate the bioavailability and brain distribution of 1,9-P. Cytotoxicity and neuroprotection were done on SH-SY5Y cell line using MTT and AO/EB apoptosis assay. The optimized batch of liposomes showed an average size of 112.33 ± 0.84 nm with a zeta potential value of -19.40 mV and 78.96 ± 0.28% drug entrapment efficiency. The in-vitro release studies demonstrated the sustained release profile of liposome up to 24 h. The pharmacokinetic data in Wistar rats over the period of 12 h demonstrated 4.82-folds greater AUC(0-12 h) for liposome in brain compared with 1,9-P suspension. Cytotoxicity assay showed no sign of toxicity, whereas apoptosis assay revealed a neuroprotective action of liposomes. The results demonstrated successful targeting of the 1,9-P, to brain as a novel strategy having significant therapeutic potential to treat PD.

Design, Development and Invivo Pharmacokinetic Evaluation of Cardiovascular Drug Loaded Nano Structured Lipid Carrier System

The Present investigation is to design, develop and optimize the Nanostructured Lipid Carrier (NLC) containing cardiovascular drug by various independent variables like formulation variables (concentration of phospholipids, surfactants, co-surfactant) and process variables (homogenization time and ultrasonication time). The objective of this research is to choose the suitable and reproducible technique for the formulation of NLC based on dependent variables like Particle Size (PS) in nm, Polydispersity Index (PDI), Zeta potential (ZP) in mV and Entrapment efficiency (EE%) by applying Box Behnken design utilizing - Multiple linear regression method (Design expert 9 software, stat-ease, Inc. USA) and another objective is to prove the enhancement of bioavailability of drug in developed NLC. Comparative invivo pharmacokinetic studies was carried out to determine AUC, Cmax, Tmax , Ke, Vd between drug loaded NLC and commercially available dosage form to prove the enhancement of bioavailability in NLC. From the results obtained, it was concluded that hot homogenization was an optimized technique for the preparation of NLC containing carvedilol and NLC shows better bioavailability when compare to commercial formulation. This data was related to the research project sanctioned by Department of science and technology (DST) entitled “Development of Lipid Nanoparticles Enriched Hydrogels for Transdermal Drug Delivery: Formulation, In vitro Characterization and Pharmacodynamic studies in Animals”

Fabrication and in-vivo evaluation of lipid nanocarriers based transdermal patch of colchicine

The present study deals with the formulation and evaluation of Solid Lipid Nanoparticles (SLNs) based transdermal patch of colchicine. Colchicine loaded SLNs (C-SLNs) were prepared by ultrasonication method and optimized with respect to the concentration of lipid and surfactant by 32 full factorial design. Properties like particle size, shape, zeta potential, polydispersity index and percentage entrapment efficiency were determined. The transdermal potential of C-SLNs was evaluated by ex-vivo drug permeation using Wistar rat skin and fluorescence microscopy. The optimized formulation was fabricated into the transdermal patch and in-vivo pharmacokinetic and pharmacodynamic study (subcutaneous air pouch model) was carried out. Particle size, zeta potential and entrapment efficiency of the optimized formulation were found to be 107 nm, (−) 17.4 mV and 37.25% respectively. Formulation F5 showed highest transdermal flux (8.76 μg/cm2/hrs). Fluorescence study confirms that SLNs have more penetration potential through the skin. AUC0→∞ of C-SLNs patch was improved by 2.84 times more than colchicine patch. Significant (p < 0.001) reduction in exudate volume, leukocyte count, and collagen deposition was observed in animals treated with C-SLNs transdermal patch. Thus, SLNs based transdermal patch of colchicine could be a promising approach for the treatment of gout.

Efavirenz loaded nanostructured lipid carrier engineered for brain targeting through intranasal route: In-vivo pharmacokinetic and toxicity study

Intranasal delivery is a potential platform that can be employed in targeting the antiretrovirals (ARVs) to reach HIV that harbors in the central nervous system. The objective of the study was to develop an optimized efavirenz (EFV) loaded nanostructured lipid carrier (ENLC) and deliver it through intranasal route for brain targeting. Factorial design (23) was used to identify the key formulation variables influencing particle size and percent drug encapsulation of efavirenz in the NLC. Optimised ENLC-6 batch exhibited a spherical morphology with a mean particle size of 162nm, high drug encapsulation of 95.78±0.42% and in-vitro drug release of 92.45% at the end of 24h. Single dose in-vivo pharmacokinetic studies revealed significant therapeutic concentration of the drug in the CNS following IN administration with a Cmax value of 31.45±0.75 and T1/2 of 11.14h. A 10 fold increase (p<0.001) in% drug targeting efficiency (DTE) and 4.5 fold increase (p<0.001) in % drug targeting potential (DTP) for ENLC-6 was observed as compared to pure EFV. Sub-acute 28day IN toxicity in experimental animals indicated non-toxicity of encapsulated efavirenz over pure drug. Based on the findings we conclude that the intelligent choice of the lipdic carrier along with the strategic use of excipients can prove helpful for the efficient brain targeting of the encapsulated efavirenz which is devoid of toxicity. This may prove useful in the management of neuro-AIDS.

Formulation and characterization of chitosan encapsulated phytoconstituents of curcumin and rutin nanoparticles

Curcumin and Rutin are natural polyphenolic molecules exhibits several pharmacological actives like antibacterial, anticancer, antioxidant, chemo-preventive and anti-inflammatory properties. However till date, no studies have been reported on their combination efficacy, especially in treating multi-drug resistance of cancers because of their poor solubility and bioavailability. Hence in the present study, an attempt has been made to load both these drugs into a single nanoparticlulate system to enhance their bioavailability and efficacy. This novel formulation was prepared by solvent evaporation technique and was evaluated for particle size and shape using Zeta Sizer, Scanning Electron Microscopy (SEM) and Fourier Transform Infra Red (FT-IR) Spectroscopy. The optimized formulation was further subjected to in vitro and in vivo evaluations. The prepared nanoparticles were in the size range of 25–100nm and the release profile was found to be Non −Fickian transport. In-vivo pharmacokinetic studies were carried in rabbits and the pharmacokinetic profile was studied. The results indicate that oral bioavailability of Curcumin and Rutin has been increased to 3.06 and 4.24 folds respectively when compared to their pure drugs. This data suggest that the present novel nanoparticles loaded with these combinational drugs may have better therapeutic potential in treating drug resistant cancers.

Zero order controlled release delivery of cholecalciferol from injectable biodegradable microsphere: In-vitro characterization and in-vivo pharmacokinetic studies

Poly(lactic-co-glycolic acid) microspheres loaded with cholecalciferol (CL), more bioactive form of vitamin D was developed as an injectable controlled drug release system and was evaluated for its feasibility of once a month delivery. The CL loaded microspheres (CL-MS) were prepared by simple oil in water (O/W) emulsion–solvent evaporation technique incorporated with a stabilizer, Tocopherol Succinate (TS). Different formulation as well as process parameters were investigated namely concentration of emulsifier, concentration of stabilizer and drug: polymer mass ratios. The prepared CL-MS were evaluated for particle size, drug loading, in-vitro drug release and in-vivo pharmacokinetics in rats. The optimized formulation was found to have a mean particle size of 28.62±0.26μm, Encapsulation Efficiency (EE) of 94.4±5.4% and drug loading of 5.19±0.29% with CL:TS ratio of 2:1. It was found that the EE drastically decreased (26±5.9%) in the absence of stabilizer (TS) indicating its role in stabilization of CL during formulation. DSC and XRD studies indicated that CL existed in an amorphous structure in the polymer matrix. SEM of the CL-MS revealed the spherical morphology and confirmed the particle size. In-vitro release showed that the CL release from CL-MS followed near zero–order drug release kinetics over nearly 1month. In-vivo pharmacokinetic study of CL-MS showed higher t1/2 (239±27.5h) compared to oily CL depot (32.7±4.8h) with sustained release of CL plasma concentration for 1month. The labile CL could thus be effectively encapsulated and protected against degradation during microspheres formulation, storage and release in presence of stabilizer. This novel CL loaded PLGA MS is stable and may have great potential for clinical use.

Effect of micro-environment modification and polymer type on the in-vitro dissolution behavior and in-vivo performance of amorphous solid dispersions

This study investigates the effects of micro-environment modification and polymer type on the in-vitro dissolution behavior and in-vivo performance of micro-environment pH modifying solid dispersions (pHM-SD) for the poorly water-soluble model drug Toltrazuril (TOL). Various pHM-SDs were prepared using Ca(OH)2 as a pH-modifier in hydrophilic polymers, including polyethylene glycol 6000 (PEG6000), polyvinylpyrrolidone k30 (PVPk30) and hydroxypropyl methylcellulose (HPMC). Based on the results of physicochemical characterizations and in-vitro dissolution testing, the representative ternary (Ca(OH)2:TOL:PEG6000/HPMC/PVPk30=1:8:24, w/w/w) and binary (TOL:PVPk30=1:3, w/w) solid dispersions were selected and optimized to perform in-vivo pharmacokinetic study. The micro-environment pH modification improved the in-vitro water-solubility and in-vivo bioavailability of parent drug TOL. Furthermore, the addition of alkalizers not only enhanced the release and absorption of prototype drug, but also promoted the generation of active metabolites, including toltrazuril sulfoxide (TOLSO) and toltrazuril sulfone (TOLSO2). The in-vitro dissolution profiles and in-vivo absorption, distribution and metabolism behaviors of the pHM-SDs varied with polymer type. Moreover, in-vivo bioavailability of three active pharmaceutical ingredients increased with an increase in in-vitro dissolution rates of the drug from the pHM-SDs prepared with various polymers. Therefore, a non-sink in-vitro dissolution method can be used to predict the in-vivo performance of pHM-SDs formulated with various polymers with trend consistency. In-vitro and in-vivo screening procedures revealed that the pHM-SD composed of Ca(OH)2, TOL and PVPk30 at a weight ratio of 1:8:24, of which the safety was adequately proved via histopathological examination, may be a promising candidate for providing better clinical outcomes.

NOVEL CHRONOTHERAPEUTIC MULTIPARTICULATE DRUG DELIVERY SYSTEM OF FELODIPINE: AN EFFECTIVE TREATMENT FOR CARDIAC ARRHYTHMIA

Arrhythmia follows chronobiology, thus necessitating development of time-dependent formulation for its treatment. The aim of the current work was to develop a solubility-enhanced chronotherapeutic system of felodipine, a widely prescribed anti-arrhythmic. Systematically optimized hot-melt extrusion process was employed to formulate solubility-enhanced extrudates. Film-casting method was adopted for the selection of polymers. Drug released at 5, 15, 30min was taken as response variables in 3 2 face-centered cube design. Nearly 10-fold increase was observed in the solubility of the optimized extrudates in comparison to pure drug. Physical characterization of the extrudates depicted complete amorphization of drug. Sequential coating was performed on to the extrudates to enable a time-dependent release. In-vitro studies clearly demonstrated that 25% of drug was available rapidly within 10 min of administration. The remaining 75% of drug was available over a period of 4, 8 and 12h. Stability studies performed for 6 months at accelerated conditions depicted no significant change in the physicochemical characteristics of the optimized formulation. In-vivo pharmacokinetic studies conducted in beagle dogs ratified the results of in-vitro studies where a sequential time dependent absorption of felodipine was observed over a period of 12h. Concisely, the studies demonstrated successful development of solubility-enhanced chronotherapeutic system of felodipine.

Formulation by design based risperidone nano soft lipid vesicle as a new strategy for enhanced transdermal drug delivery: In-vitro characterization, and in-vivo appraisal

The present study was designed to formulate and optimize transdermal risperidone soft lipid vesicles. The formulation optimized with phospholipid, safranal and ethanol were incorporated as permeation and absorption enhancers. The optimized risperidone soft lipid vesicle was further evaluated for skin irritation study, in-vivo pharmacokinetic study and locomotor activity. Three factor three level Box–Behnken design (BBD) was used to statistically optimize soft lipid vesicle using safranal (A), ethanol (B)and phospholipid (C) as independent variable, while their effect was observed for vesicle size (Y1), entrapment efficiency (Y2) and flux (Y3). The optimized risperidone soft lipid vesicle (Ris-opt) showed nanometric vesicle size, high entrapment efficiency and marked enhancement in transdermal flux. The extent of absorption from Ris-opt was greater when compared to oral suspension with relative bioavailability of 177%. The histopathological evaluation revealed developed formulation did not showed skin irritation compared to standard irritant. The significant findings presented here encourage further studies with risperidone soft lipid vesicles for treatment of schizophrenia.

Systematic Approach for the Formulation and Optimization of Solid Lipid Nanoparticles of Efavirenz by High Pressure Homogenization Using Design of Experiments for Brain Targeting and Enhanced Bioavailability.

The nonnucleoside reverse transcriptase inhibitors, used for the treatment of HIV infections, are reported to have low bioavailability pertaining to high first-pass metabolism, high protein binding, and enzymatic metabolism. They also show low permeability across blood brain barrier. The CNS is reported to be the most important HIV reservoir site. In the present study, solid lipid nanoparticles of efavirenz were prepared with the objective of providing increased permeability and protection of drug due to biocompatible lipidic content and nanoscale size and thus developing formulation having potential for enhanced bioavailability and brain targeting. Solid lipid nanoparticles were prepared by high pressure homogenization technique using a systematic approach of design of experiments (DoE) and evaluated for particle size, polydispersity index, zeta potential, and entrapment efficiency. Particles of average size 108.5 nm having PDI of 0.172 with 64.9% entrapment efficiency were produced. Zeta potential was found to be −21.2 mV and the formulation was found stable. The in-vivo pharmacokinetic studies revealed increased concentration of the drug in brain, as desired, when administered through intranasal route indicating its potential for an attempt towards complete eradication of HIV and cure of HIV-infected patients.

In vitro and in vivo effects of morin on the intestinal absorption and pharmacokinetics of olmesartan medoxomil solid dispersions

Purpose: In-situ evaluation to corroborate morin effects on the intestinal absorption and pharmacokinetic behavior of freeze-dried OLM-loaded solid dispersions with Caco-2 and in-vivo studiesMethods: Intestinal transport and absorption studies were examined by Caco-2 permeability, in-situ single pass perfusion and closed-loop models along with in-vivo pharmacokinetic studies to evaluate and confirm the effect of P-gp-mediated activity of morin. We evaluated the intestinal membrane damage in the presence of morin by measuring the release of protein and lactate dehydrogenase (LDH) followed by using qualitative and quantitative morphometric analysis to describe the surface characteristics of intestinal epithelium.Results: Morin showed the highest Peff value 13.8 ± 0.34 × 10−6 cm/s in jejunum than ileum (p < .01) at 100 µM with absorption enhancement of 1.31-fold together with enhanced (p < .01) secretory transport of 6.27 ± 0.27 × 10 −6 cm/s in Caco-2 monolayer cells. Our findings noticed 2.37 (in-situ); 2.39 (in-vivo) and 1.43 (in-situ); 1.36 (in-vivo) fold increase in AUC0–t with elevated Cmax and shortened Tmax for freeze-dried solid dispersion in the presence of morin as compared to pure OLM and freeze-dried solid dispersions without morin, respectively.Conclusions: Our study demonstrated that increased solubilization through freeze-dried OLM-loaded solid dispersion together with efflux inhibition improved intestinal permeability to one system that might lead to novel solubilization and efflux pump inhibition as a novel alternative potential to increase oral absorption and bioavailability of OLM.

Special remarks: Alcoholic pancreatitis in the modern era

The present work evaluates the synergistic anticancer efficacy of bioactive Hydroxyapatite (HA) nanoparticles (HA NPs) loaded with Bendamustine HCl. Hydroxyapatite is a material with an excellent biological compatibility, a well-known fact which was also supported by the results of the Hemolytic studies and a high IC50 value observed in the MTT assay. HA NPs were prepared by the chemical precipitation method and loaded with the drug via physical adsorption. In-vitro release study was performed, which confirmed the sustained release of the drug from the drug loaded HA NPs. MTT assay, Cell Uptake and FACS studies on JURKAT E6.1 cell line and in-vivo pharmacokinetic studies in Wistar rats revealed that the drug loaded HA NPs could be easily internalized by the cells and release drug in a sustained manner. The drug loaded HA NPs showed cytotoxicity similar to the drug solution at 1/10th of the drug content, which indicates a possible synergism between the activity of the anticancer drug and calcium ions derived from the carrier. An increase in intracellular Ca2+ ions is reported to induce apoptosis in cells. Tumor regression study in Balb/c mice Ehrlich⿿s ascites model presented a similar synergistic efficacy. The drug solution was able to decrease the tumor volume by half, while the drug loaded HA NPs reduced the tumor size by 6 times.

Synergistic anticancer efficacy of Bendamustine Hydrochloride loaded bioactive Hydroxyapatite nanoparticles: In-vitro, ex-vivo and in-vivo evaluation

The present work evaluates the synergistic anticancer efficacy of bioactive Hydroxyapatite (HA) nanoparticles (HA NPs) loaded with Bendamustine HCl. Hydroxyapatite is a material with an excellent biological compatibility, a well-known fact which was also supported by the results of the Hemolytic studies and a high IC50 value observed in the MTT assay. HA NPs were prepared by the chemical precipitation method and loaded with the drug via physical adsorption. In-vitro release study was performed, which confirmed the sustained release of the drug from the drug loaded HA NPs. MTT assay, Cell Uptake and FACS studies on JURKAT E6.1 cell line and in-vivo pharmacokinetic studies in Wistar rats revealed that the drug loaded HA NPs could be easily internalized by the cells and release drug in a sustained manner. The drug loaded HA NPs showed cytotoxicity similar to the drug solution at 1/10th of the drug content, which indicates a possible synergism between the activity of the anticancer drug and calcium ions derived from the carrier. An increase in intracellular Ca2+ ions is reported to induce apoptosis in cells. Tumor regression study in Balb/c mice Ehrlich⿿s ascites model presented a similar synergistic efficacy. The drug solution was able to decrease the tumor volume by half, while the drug loaded HA NPs reduced the tumor size by 6 times.

Bioavailability enhancement and pharmacokinetic profile of an anticancer drug ibrutinib by self-nanoemulsifying drug delivery system.

The current studies were undertaken to enhance dissolution and bioavailability/pharmacokinetic profile of a newly approved anticancer drug ibrutinib (IBR) via encapsulation of drug into self-nanoemulsifying drug delivery system (SNEDDS). Various SNEDDS formulations of IBR were developed by aqueous phase titration method using Capryol-PGMC (oil phase), Tween-20 (surfactant), Carbitol (cosurfactant) and water (aqueous phase). Developed SNEDDS of IBR was evaluated in vitro for various physicochemical properties and drug release profile. Based on lowest droplet size (28.7 ± 3.2 nm), least polydispersity (0.123), optimal values of zeta potential (-32.8 mV) and refractive index (1.336), highest % transmittance (98.7 ± 0.2%), highest drug release profile via dialysis membrane (98.9 ± 8.2% after 48 h) and the presence of lowest concentration of Capryol-PGMC (12% w/w), SNEDDS I1 was selected for in-vivo pharmacokinetic/bioavailability studies in female Wistar rats. In-vivo pharmacokinetic studies in rats showed that optimized SNEDDS I1 controlled the absorption of IBR compared with IBR suspension. The bioavailability of IBR from optimized SNEDDS I1 was enhanced around 2.64 times in comparison with IBR suspension. These results indicated the potential of developed SNEDDS as an alternative drug delivery system for IBR to enhance its bioavailability and anticancer efficacy.

Revisiting bone targeting potential of novel hydroxyapatite based surface modified PLGA nanoparticles of risedronate: Pharmacokinetic and biochemical assessment

Hydroxyapatite based biodegradable mPEG-PLGA nanoparticles of risedronate (mPEG-PLGA-RIS-HA) were prepared by water miscible dialysis method for synergistic treatment of osteoporosis. The bone targeting potential of prepared nanoparticles was evaluated by performing the cell viability study and protein estimation in pre-osteoblast cell line (MC3T3E1). Biochemical and in-vivo pharmacokinetic studies on osteoporotic rat model treated with different formulations were performed. Under the biochemical study ALP, TRAP, HxP and Calcium levels were determined. Osteoporotic model treated with prepared nanoparticles indicated significant effect on bone. Pharmacokinetic studies revealed 6-fold and 4-fold increase in the relative bioavailability after intravenous and oral administration of nanoparticles respectively as compared to marketed formulation confirming better effective drug transport. Biochemical investigations also showed a significant change in biomarker level which ultimately lead to bone formation/resorption. A stability analysis has also been carried out according to ICH guidelines (Q1AR2) and shelf life was found to be 1year and 4 months for the prepared formulation. Thus the results of present studies indicated that mPEG-PLGA-RIS-HA NPs has a great potential for sustained delivery of RIS for the treatment and prevention of osteoporosis and to minimize the adverse effects of RIS typically induced by its oral administration.

Artificial Neural Network Analysis of Pharmacokinetic and Toxicity Properties of Lead Molecules for Dengue Fever, Tuberculosis and Malaria.

Poor pharmacokinetic and toxicity profiles are major reasons for the low rate of advancing lead drug candidates into efficacy studies. The In-silico prediction of primary pharmacokinetic and toxicity properties in the drug discovery and development process can be used as guidance in the design of candidates. In-silico parameters can also be used to choose suitable compounds for in-vivo testing thereby reducing the number of animals used in experiments. At the Novartis Institute for Tropical Diseases, a data set has been curated from in-house measurements in the disease areas of Dengue, Tuberculosis and Malaria. Volume of distribution, half-life, total in-vivo clearance, in-vitro human plasma protein binding and in-vivo oral bioavailability have been measured for molecules in the lead optimization stage in each of these three disease areas. Data for the inhibition of the hERG channel using the radio ligand binding dofetilide assay was determined for a set of 300 molecules in these therapeutic areas. Based on this data, Artificial Neural Networks were used to construct In-silico models for each of the properties listed above that can be used to prioritize candidates for lead optimization and to assist in selecting promising molecules for in-vivo pharmacokinetic studies.

Highly water-soluble mast cell stabiliser-encapsulated solid lipid nanoparticles with enhanced oral bioavailability

Cromolyn sodium (CS), a mast cell stabiliser, is widely employed for the prevention and treatment of allergic conditions. However, high hydrophilicity and poor oral permeability hinder its oral clinical translation. Here, solid lipid nanoparticles (SLNs) have been developed for the purpose of oral bioavailability enhancement. The CS–SLNs were engineered by double emulsification method (W1/O/W2) and optimised by using Box–Behnken experimental design. The surface and solid-state characterisations revealed the presence of CS in an amorphous form without any interactions inside the spherical-shaped SLNs. The in-vitro release study showed an extended release up to 24 hr by diffusion controlled process. Ex-vivo and in-vivo intestinal permeation study showed ∼2.96-fold increase in permeability of CS by presentation as SLNs (p < 0.05). Further, in-vivo pharmacokinetic study exhibited ∼2.86-fold enhancements in oral bioavailability of CS by encapsulating inside SLNs, which clearly indicate that SLNs can serve as the potential therapeutic carrier system for oral delivery of CS.

Clinical research on double- “U” embedding and pursestring suture and bind style pancreaticojejunostomy for the prevention of pancreatic leakage

The present work evaluates the synergistic anticancer efficacy of bioactive Hydroxyapatite (HA) nanoparticles (HA NPs) loaded with Bendamustine HCl. Hydroxyapatite is a material with an excellent biological compatibility, a well-known fact which was also supported by the results of the Hemolytic studies and a high IC50 value observed in the MTT assay. HA NPs were prepared by the chemical precipitation method and loaded with the drug via physical adsorption. In-vitro release study was performed, which confirmed the sustained release of the drug from the drug loaded HA NPs. MTT assay, Cell Uptake and FACS studies on JURKAT E6.1 cell line and in-vivo pharmacokinetic studies in Wistar rats revealed that the drug loaded HA NPs could be easily internalized by the cells and release drug in a sustained manner. The drug loaded HA NPs showed cytotoxicity similar to the drug solution at 1/10th of the drug content, which indicates a possible synergism between the activity of the anticancer drug and calcium ions derived from the carrier. An increase in intracellular Ca2+ ions is reported to induce apoptosis in cells. Tumor regression study in Balb/c mice Ehrlich⿿s ascites model presented a similar synergistic efficacy. The drug solution was able to decrease the tumor volume by half, while the drug loaded HA NPs reduced the tumor size by 6 times.

Biological evaluation of PEG modified nanosuspensions based on human serum albumin for tumor targeted delivery of paclitaxel

Since its approval by the FDA, Abraxane™ has been established as a clinical standard of paclitaxel (PTX)-based therapy against a variety of cancers. Despite success, Abraxane™ is still limited by suboptimal biodistribution, unfavorable pharmacokinetics and chronic toxicities from chloroform used during preparation. Accordingly, a PTX-loaded nanosuspension based on human serum albumin (HSA) with PEG modifiers (PTX-PEG-HSA) has been developed to optimize the in-vivo biodistribution, pharmacokinetics and safety of PTX over traditional PTX-HSA nanosuspensions prepared using the accepted method for Abraxane™. Results of in-vivo pharmacokinetic (PK) studies indicated PTX-PEG-HSA achieved prolonged blood circulation, illustrated by an 8.8-fold and 4.8-fold increase in area-under-the-curve (AUC) of PTX over Taxol® and PTX-HSA, while the mean residence time (MRT) of PTX in PTX-PEG-HSA was increased by 3.2-fold and 1.5-fold, respectively. HSA mediated active targeting further suppressed non-specific distribution of PTX to normal tissues, which permitted enhanced antitumor efficacy in S180 mice over Taxol® and PTX-HSA. Safety of intravenously administered PTX-PEG-HSA was confirmed through lower hemolytic activity, a 2.2-fold and 1.2-fold increase in LD50 (113.4mg/kg) over Taxol® and PTX-HSA alongside the absence of local venous irritation. Studies herein suggest the therapeutic and clinical applicability of PTX-PEG-HSA for tumor specific therapy.