Co-delivery of gemcitabine and simvastatin through PLGA polymeric nanoparticles for the treatment of pancreatic cancer: in-vitro characterization, cellular uptake, and pharmacokinetic studies.

Despite the ongoing extensive research, cancer therapeutics still remains an area with unmet needs which is hampered by shortfall in the development of newer medicines. The present study discusses a nano-based combinational approach for treating solid tumor. Dual-loaded nanoparticles encapsulating gemcitabine HCl (GM) and simvastatin (SV) were fabricated by double emulsion solvent evaporation method and optimized. Optimized nanoparticles showed a particle size of 258 ± 2.4 nm, polydispersity index of 0.32 ± 0.052, and zeta potential of -12.5 mV. The size and the morphology of the particles wee further confirmed by transmission electron microscopy (TEM) and scanning electron microscopy, respectively of the particles. The entrapment efficiency of GM and SV in the nanoparticles was 38.5 ± 4.5% and 72.2 ± 5.6%, respectively. The in vitro release profile was studied for 60 h and showed Higuchi release pattern. The cell toxicity was done using MTT assay and lower IC50 was obtained with the nanoparticles as compared to the pure drug. The bioavailability of GM and SV in PLGA nanoparticles was enhanced by 1.4-fold and 1.3-fold respectively, compared to drug solution. The results revealed that co-delivery of GM and SV could be used for its oral delivery for the effective treatment of pancreatic cancer.

Preparation and Preclinical Evaluation of Inhalable Particles Containing Rapamycin and Anti-Tuberculosis Agents for Induction of Autophagy.

PURPOSE: Mycobacterium tuberculosis (Mtb) inhibits host defense mechanisms, including autophagy. We investigated particles containing rapamycin (RAP) alone or in combination with isoniazid (INH) and rifabutin (RFB) for: targeting lung macrophages on inhalation; inducing autophagy; and killing macrophage-resident Mtb and/or augmenting anti-tuberculosis (TB) drugs. METHODS: PLGA and drugs were spray-dried. Pharmacokinetics, partial biodistribution (LC-MS/MS) and efficacy (colony forming units, qPCR, acid fast staining, histopathology) in mice following dry powder inhalation were evaluated. RESULTS: Aerodynamic diameters of formulations were 0.7-4.7 µm. Inhaled particles reached deep lungs and were phagocytosed by alveolar macrophages, yielding AUC0-48 of 102 compared to 0.1 µg/ml × h obtained with equivalent intravenous dose. RAP particles induced more autophagy in Mtb-infected macrophages than solutions. Inhaled particles containing RAP alone in daily, alternate-day and weekly dosing regimens reduced bacterial burden in lungs and spleens, inducing autophagy and phagosome-lysosome fusion. Inhalation of particles containing RAP with INH and RFB cleared the lungs and spleens of culturable bacteria. CONCLUSIONS: Targeting a potent autophagy-inducing agent to airway and lung macrophages alone is feasible, but not sufficient to eliminate Mtb. Combination of macrophage-targeted inhaled RAP with classical anti-TB drugs contributes to restoring tissue architecture and killing Mtb.

Fusion and self-assembly of biodegradable polymer particles into scaffoldlike and membranelike structures at room temperature for regenerative medicine.

We report here a novel surfactant mediated fusion of polylactide particles into scaffoldlike structures at room temperature. In the presence of ethanol, evenly spread surfactant coated polylactide particles fused immediately into membranelike structures. Polymer scaffolds of the desired shape and size could be fabricated from polylactide particles using this fusion process. Desorption of surfactant molecules from the surface of the particles during ethanol treatment and the degree of solubility of the polymer in alcohol were found to be the main reasons for the fusion of particles into a scaffold at room temperature. TGA and DSC studies of the polylactide particles showed that the particles were stable at room temperature, and FTIR studies showed that there was no change in characteristics of the polymer after the fusion of particles into a scaffold-type structure. These scaffolds supported three-dimensional growth of animal cells in vitro and release model protein in a sustained manner for a long period of time. In an experimental animal wound model, the polylactide membranes showed faster wound closure, indicating its use as a passive dressing material. This polymer particle fusion process thus provides a novel method of scaffold fabrication for various biomedical applications.

Development of enteric submicron particles formulation of α-amylase for oral delivery.

Enteric submicron particles (SPs) formulations of α-amylase were prepared by w/o/w emulsion solvent evaporation using hydroxypropyl methylcellulose phthalate (HPMCP) and Eudragit L 100, to avoid gastric inactivation of α-amylase. Smaller internal and external aqueous phase volume provided maximum encapsulation efficiency (71.92-73.40%), least particle size (546.4-595.4 nm) and 23-26% loss of enzyme activity. Release studies in 0.1 N HCl confirmed the gastro-resistance of formulations. The anionic SPs aggregated in 0.1 N HCl (i.e. gastric pH 1.2), due to protonation of carboxylic groups of enteric polymer. The aggregates being < 500 µm size would not impede gastric emptying. However, at pH >5.0 (duodenal pH), SPs showed de-aggregation due to restoration of surface charge. HPMCP and Eudragit L 100 SPs facilitated almost complete release of α-amylase within 30 min at pH 6.0 and 6.8, respectively, following Higuchi kinetics. PXRD and DSC indicated amorphous character and scanning electron microscope showed spherical shape of SPs. In simulated gastro-intestinal pH condition, HPMCP and Eudragit L 100 SPs showed good digestion of cooked rice and could serve as potential carrier for oral enzyme delivery. Stability studies indicated the formulations as quite stable to ensure 2 years shelf life at room temperature.

Immunogenicity Evaluation of Thermostable Microparticles Entrapping Receptor Binding Domain of SARS-CoV-2 by Single Point Administration.

Receptor binding domain (RBD) of SARS-CoV-2 is a prime vaccine target against which neutralizing antibody responses are directed. Purified RBD as a vaccine candidate warrants administration of multiple doses along with adjuvants and use of delivery systems to improve its immunogenicity. The present investigation examines the immunogenicity of RBD delivered by biodegradable polymer particles from single dose administration. Mice upon single point immunization of RBD entrapped microparticles generated improved antibody response. The polymer microparticles showed better temperature stability and could be stored at 37 degrees for one month without any considerable loss of immunogenicity. Further, immunization with microparticles could elicit memory antibody response upon challenge after four months of single dose administration. Thus, using microparticles entrapping RBD as a vaccine candidate confer improved immunogenicity, temperature stability and recall response. These thermostable microparticles seem to be a potentially cost-effective approach which can help in dose reduction, provide a wider access of vaccines and accelerate the end of global pandemic.

Controlled release of bioactive recombinant human growth hormone from PLGA microparticles.

Controlled release formulation of recombinant human growth hormone (r-hGH) was achieved using poly lactide-co-glycolide (PLGA) polymer. Denaturation of r-hGH by dichloromethane during primary emulsification step of particle preparation was minimized by using human serum albumin whereas inclusion of sucrose and sodium bicarbonate helped in reducing protein denaturation during lyophilization and polymer particle degradation. Encapsulation efficiency of r-hGH entrapped in PLGA particles (size approximately 30 microm) was around 45% with protein load 20 microg of r-hGH/mg of polymer particles. Porous particles showed quick release of r-hGH in comparison to non-porous particles in vitro. More than 10 ng/mL of bioactive r-hGH was found in the serum of the experimental animals observed for a 30-day period after a single intramuscular injection of the polymeric formulation. Incorporation of optimal stabilizers is thus essential for the development of a stable, month long controlled release of polymer particle based r-hGH formulation.

Design, in vitro and in vivo evaluation of glipizide Eudragit microparticles.

Glipizide microparticles made with Eudragit (RS 100 and RL 100), prepared by emulsion solvent evaporation technique were evaluated for various in-vitro properties viz. encapsulation efficiency, particle size and surface morphology, drug release pattern and in-vivo hypoglycaemic activity. The optimized formulation parameters were used to prepare smooth and spherical microparticles (2-32 microm) with higher entrapment efficiency (67-89%). Drug release patterns of glipizide microparticles of Eudragit RS 100 and Eudragit RL 100 with drug-to-polymer ratio of 1 : 4 (i.e. EGM14 and ELGM14) have shown gradual and extended release for 24 h with cumulative release of glipizide to the extent of 72.3% and 83.9%, respectively. However, EGM14 showed a significant in-vivo hypoglycaemic effect up to 12 h in rabbits while ELGM14 showed for 9 h. Hence, glipizide microparticles of Eudragit RS 100 (glipizide: polymer 1 : 4) is better suited for oral sustained release formulation.

Formulation, characterization and evaluation of rotavirus encapsulated PLA and PLGA particles for oral vaccination.

Polylactide (PLA) and polylactide-co-glycolide (PLGA) particles entrapping rotavirus (strain SA11) were formulated using a solvent evaporation technique. To minimize denaturation of viral antigen during the emulsification process, serum albumin was used as a stabilizer. Use of NaHCO(3) and sucrose during the primary emulsification step resulted in uniform stabilized particles entrapping rotavirus. Sonication during the primary emulsion and homogenization during the secondary emulsion process resulted in particles of sizes 2-8 microm, whereas nanoparticles were formed when sonication was used during both primary and secondary emulsion processes. Scanning electron and atomic force microscopy showed uniform pores and roughness throughout the polymer particle surface. Single dose oral immunization with 20 microg of antigen entrapped in PLA particles elicited improved and long-lasting IgA and IgG antibody titer in comparison to the soluble antigen. The study shows results illustrating the usefulness of polymeric microparticles as a potential oral delivery system for rotavirus vaccine.

Gemcitabine and betulinic acid co-encapsulated PLGA-PEG polymer nanoparticles for improved efficacy of cancer chemotherapy.

The present study demonstrated the development of gemcitabine and betulinic acid co-encapsulated PLGA-PEG polymer nanoparticles for enhancing the chemotherapeutic response. This combinatorial PLGA-PEG nanoparticle was formulated using double emulsion and had size <200 nm. The developed nanoparticles were characterized using dynamic light scattering and transmission electron microscopy for their size and shape, respectively. The in vitro release of the drugs from combinatorial nanoparticles was predominantly followed by Fickian diffusion phenomenon. Study on hemocompatibilty approved the administration of this combinatorial nanoparticle for animal study. In vitro cytotoxicity study on Panc1 cells using MTT assay, reactive oxygen species production and cellular apoptotic assay demonstrated that combinatorial nanoparticle was more cytotoxic compared to native drugs solution. Furthermore, the combinatorial nanoparticle suppressed tumor growth more efficiently in Ehrlich (solid) tumor model than the native gemcitabine and betulinic acid at the same concentrations. These findings indicated that PLGA-PEG nanoparticle might be used to co-deliver multiple chemotherapeutic drugs with different properties for enhancing antitumor efficacy.

Improved bioavailability of orally delivered insulin using Eudragit-L30D coated PLGA microparticles.

Large porous microparticles of PLGA entrapping insulin were prepared by solvent evaporation method and evaluated in diabetes induced rat for its efficacy in maintaining blood sugar level from a single oral dose. Incorporation of Eudragit L30D (0.03% w/v) in the external aqueous phase resulted in formation of pH responsive enteric coated polymer particles which release most of the entrapped insulin in alkaline pH. At acidic pH, release of insulin from uncoated PLGA microparticles and Eudragit L30D coated PLGA microparticles was 31.62 +/- 1.8% and 17.5 +/- 1.29%, respectively, for initial 30 min. However, in 24 h, in vitro released insulin from uncoated PLGA and Eudragit coated particles was 96.29 +/- 1.01% and 88.30 +/- 1%, respectively. Released insulin from composite polymer particles were mostly in monomer form without aggregation and was stable for a month at 37 degrees C. Oral administration of insulin loaded PLGA (50 : 50) and Eudragit L30D coated PLGA (50 : 50) microparticles (equivalent to 25 IU insulin/kg of animal weight) in alloxan induced diabetic rats resulted in 37.3 +/- 11% and 62.7 +/- 3.8% reduction in blood glucose level, respectively, in 2 h. This effect continued up to 24 h in the case of Eudragit L30D coated PLGA microparticles. Results demonstrate that use of stabilizers during PLGA particle formulation, large porous particle for quick release of insulin and coating with Eudragit L30D resulted in a novel oral formulation for once a day delivery of insulin.

Highly Biocompatible, Fluorescence, and Zwitterionic Carbon Dots as a Novel Approach for Bioimaging Applications in Cancerous Cells.

Highly biocompatible, excellently photostable, nitrogen- and sulfur-containing novel zwitterionic carbon dots (CDs) were synthesized by microwave-assisted pyrolysis. The size of CDs were 2-5 nm, with an average size of 2.61 ± 0.7 nm. CDs were characterized by UV/vis spectroscopy, fluorescence spectroscopy, zeta potential, Fourier-transform infrared spectroscopy, X-ray diffraction, and time-resolved fluorescence spectroscopy. CDs were known to emit blue fluorescence when excited at 360 nm, that is, UV region, and emit in the blue region of visible spectrum, that is, at 443 nm. CDs showed excitation-independent photoluminescence behavior and were highly fluorescent even at lower concentration under UV light. These CDs were highly fluorescent in nature, with the quantum yield being as high as 80%, which is comparable to that of organic dyes. The CDs were further used to image two different oral cancer cell lines, namely, FaDu (human pharyngeal carcinoma) and Cal-27 (human tongue carcinoma). The cell viability assay demonstarted that CDs were highly biocompatible, which was further confirmed by the side scattering studies as no change in the granularity was observed even at the highest concentration of 1600 µg/mL. The generation of reactive oxygen species (ROS) was also investigated and negligible generaton of ROS was detected. In addition to that, the uptake phenomenon, cell cycle analysis, exocytosis, and cellular uptake at 4 °C and in the presence of ATP inhibitor were studied. It was found that CDs easily cross the plasma membrane without hampering the cellular integrity.

Formulation and optimization of topotecan nanoparticles: In vitro characterization, cytotoxicity, cellular uptake and pharmacokinetic outcomes.

The study focuses on widening up the therapeutic perspective of anti-cancer therapy by entrapping a hydrophilic anticancer drug, topotecan hydrochloride (TOPO) in biodegradable poly (lactide-co-glycolide) (PLGA) matrix to form topotecan nanoparticles (TOPO NPs) by a double emulsion solvent evaporation technique. Statistical optimization using Box-Behnken design showed that sonication time of primary emulsion for 120 s, drug: polymer ratio of 1:12.65, organic phase: external aqueous phase ratio of 1:2.82 and 0.5% w/v of polyvinyl alcohol in the drug containing phase produced TOPO NPs with a size of 243.2 ±â€¯4 nm and an entrapment efficiency of 60.9 ±â€¯2.2%. TOPO NPs illustrated sustained release of TOPO for a week in phosphate buffer saline (PBS) at simulating physiological (pH 7.4) and acidic tumor microenvironmental (pH 6.5) conditions. A dramatic increase in cellular uptake with a corresponding enhanced cytotoxic potency was also displayed by TOPO NPs against human ovarian cancer cells (SKOV3) over time as compared to native drug, TOPO. These findings were further supported by the enhancement of bioavailability (13.05 fold) conferred by TOPO NPs from the in vivo pharmacokinetic study. The study represents a logistic approach for formulating TOPO NPs which can be used as an effective drug delivery system for the treatment of ovarian cancer.

CD44 targeted PLGA nanomedicines for cancer chemotherapy.

In recent years scientific community has drawn a great deal of attention towards understanding the enigma of cluster of differentiation-44 (CD44) in order to deliver therapeutic agents more selectively towards tumor tissues. Moreover, its over-expression in variety of solid tumors has attracted drug delivery researchers to target this receptor with nanomedicines. Conventional nanomedicines based on biodegradable polymers such as poly(lactide-co-glycolide) (PLGA) are often associated with insufficient cellular uptake by cancer cells, due to lack of active targeting moiety on their surface. Therefore, to address this limitation, CD44 targeted PLGA nanomedicines has gained considerable interest for enhancing the efficacy of chemotherapeutic agents. In this review, we have elaborately discussed the recent progress in the design and synthesis of CD44 targeted PLGA nanomedicines used to improve tumor-targeted drug delivery. We have also discussed strategies based on co-targeting of CD44 with other targeting moieties such as folic acid, human epidermal growth factor 2 (HER2), monoclonal antibodies using PLGA based nanomedicines.

Interactions of antigen-loaded polylactide particles with macrophages and their correlation with the immune response.

Size of the polymeric particulate antigen delivery system and its interactions with antigen-presenting cells (APCs) influence the immune response both qualitatively and quantitatively. In this paper, we report that antigen-loaded polymeric microparticles elicit antibody titers without being phagocytosed by macrophages; and size of the antigen-loaded particles modulates immune response from single-point immunization. Antibody titers varied significantly from single-point immunization with different sized polylactide (PLA) particles entrapping hepatitis B surface antigen. Nanoparticles (200-600 nm) were efficiently taken up by macrophages and elicited lower antibody titers in comparison to microparticles (2-8 microm). PLA microparticles that elicited highest and long-lasting antibody titers from single-point immunization were not taken up by the macrophages and found attached to the surface of the macrophages. Immunization with nanoparticles (200-600 nm) was associated with higher levels of IFN-gamma production, upregulation of MHC class I molecules along with antibody isotypes favoring Th1-type immune response. Immunization with microparticles (2-8 microm size) promoted IL-4 secretion, upregulated MHC class II molecules and favored Th2-type immune response. Western blot analysis showed that release of HBsAg from surface-attached microparticles into macrophages increased with time, but was more or less constant in case of nanoparticles. Our results suggest that continuous release of high concentration of antigen from cell surface-attached PLA microparticles into APCs results in improved antibody response from single-point immunization. It also offers an exciting possibility of designing size-based polymer particle delivery system to modulate immune response.

Design and evaluation of antibiotic releasing self- assembled scaffolds at room temperature using biodegradable polymer particles.

Biodegradable polymer-based drug-eluting implants offer many advantages such as predictable drug release kinetics, safety, and acceptable drug loading under ambient conditions. Herein, we describe fabrication and evaluation of antibiotic loaded scaffolds for localized delivery and tissue engineering applications. PDLLA particles entrapping gentamycin were formulated using solvent evaporation method and used for scaffold fabrication. Optimization of formulation parameters such as pH of the internal aqueous phase and combination of excipients like glycerol, polyvinyl alcohol (PVA) resulted in high entrapment efficiencies up to 96% of gentamicin in particles with drug load of 16-18µg/mg of polymer particles. These microparticles were fused in presence of methanol at ambient temperatures to form scaffolds of different geometry having reasonable mechanical strength. Porosity of these scaffolds was found to be more than 80%. Antibiotic released from the scaffolds was found to be bioactive as tested against Staphylococcus aureus and the release pattern was biphasic over a period of one week. The scaffolds were found to be non-toxic to murine fibroblasts cultures in vitro as well as to mice upon subcutaneous implantation. This method provides a novel and easy way of fabricating antibiotic loaded polymer scaffolds for varieties of applications.

Development and evaluation of long-circulating nanoparticles loaded with betulinic acid for improved anti-tumor efficacy.

The clinical application of betulinic acid (BA), a natural pentacyclic triterpenoid with promising antitumor activity, is hampered due to its extremely poor water solubility and relatively short half-life in the systemic circulation. In order to address these issues, herein, we developed betulinic acid loaded polylactide-co-glycolide- monomethoxy polyethylene glycol nanoparticles (PLGA-mPEG NPs). The PLGA-mPEG co-polymer was synthesized and characterized using NMR and FT-IR. BA loaded PLGA-mPEG NPs were prepared by an emulsion solvent evaporation method. The developed nanoparticles had a desirable particle size (∼147nm) and exhibited uniform spherical shape under transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The PLGA-mPEG NPs were able to decrease the uptake by macrophages (i.e. J774A.1 and Raw 264.7 cells) as compared to PLGA nanoparticles. In vitro cytotoxicity in MCF7 and PANC-1 cells demonstrated enhanced cytotoxicity of BA loaded PLGA-mPEG NPs as compared to free BA. The cellular uptake study in both the cell lines demonstrated time dependent uptake behavior. The enhanced cytotoxicity of BA NPs was also supported by increased cellular apoptosis, mitochondrial membrane potential loss, generation of high reactive oxygen species (ROS) and cell cycle arrest. Further, intravenous pharmacokinetics study revealed that BA loaded PLGA-mPEG NPs could prolong the circulation of BA and remarkably enhance half-life by ∼7.21 folds. Consequently, in vivo studies in Ehrlich tumor (solid) model following intravenous administration demonstrated superior antitumor efficacy of BA NPs as compared to native BA. Moreover, BA NPs treated Ehrlich tumor mice demonstrated no biochemical, hematological and histological toxicities. These findings collectively indicated that the BA loaded PLGA-mPEG NPs might serve as a promising nanocarrier for improved therapeutic efficacy of betulinic acid.

Influences of excipients on in vitro release and in vivo performance of tetanus toxoid loaded polymer particles.

Protein instability during microencapsulation has been one of the major hurdles of biodegradable polymer particles-based vaccine delivery systems. In the present work, effect of serum albumin, sucrose and sodium bicarbonate on surface morphology, entrapment efficiency, in vitro release and in vivo performance tetanus toxoid (TT) loaded PLA particles were investigated. Use of serum albumin as well as high concentration of protein antigen ( approximately 60mg/ml) helped in protecting the immunoreactivity of the antigen during primary emulsification step of particle formulation. Incorporation of sucrose in the internal aqueous phase led to the reduction in encapsulation efficiency of TT from 43.8+/-4.3% to 27.3+/-3.6% in PLA particles and resulted with formation of particles having irregular surface characteristics. Addition of sodium bicarbonate along with sucrose during primary emulsion led to slight improvement in encapsulation efficiency of TT (34.3+/-3.2%) but affected the in vivo performance in terms of serum anti-TT antibody titers from single point immunization. Restoration of osmotic balance by adding equivalent amount of sucrose in external aqueous phase helped in preventing multiple emulsion instability and subsequently improved the encapsulation efficiency of TT to 63.1+/-4.2%. Maximum entrapment efficiency of TT up to 69.2+/-5.1% was achieved when serum albumin, sucrose and sodium bicarbonate were used in internal aqueous phase and sucrose was used in the external aqueous phase. Polymer particles entrapping tetanus toxoid along with optimal stabilizers showed burst release of immunoreactive antigen (>40% in early period) and elicited high and sustained anti-TT antibody titers from single point intramuscular immunization. Anti-TT antibody titers were further enhanced upon immunization of admixture of PLA particles and alum. Choice and use of stabilizers during particle formulation thus need careful considerations not only to protect the immunoreactivity of the antigen, but also to produce stable, uniform particles for optimal in vivo performances.

Investigation of imatinib loaded surface decorated biodegradable nanocarriers against glioblastoma cell lines: Intracellular uptake and cytotoxicity studies.

Overexpression of P-glycoprotein (P-gp) efflux transporter in glioma cells thwarts the build-up of therapeutic concentration of drugs usually resulting into poor therapeutic outcome. To surmount aforesaid challenge, Imatinib (IMM) loaded Poly-lactide-co-glycolic acid nanoparticles (IMM-PLGA-NPs) were developed and optimized by Box Behnken Design as a new treatment stratagem in malignant glioma. Optimized NPs were functionalized with Pluronic(®) P84, P-gp inhibitor (IMM-PLGA-P84-NPs) which showed size, PDI, zeta potential, drug loading, 182.63±13.56nm, 0.196±0.021, -15.2±1.49mV, 40.63±2.04µg/mg, respectively. Intracellular uptake study conducted on A172, U251MG and C6 glioma cells demonstrated significantly high uptake of IMM through NPs when compared with IMM solution (IMM-S), p<0.001. IMM-PLGA-P84-NPs showed better uptake in P-gp expressing cell line (U251MG and C6) while uncoated NPs showed higher uptake in non-P-gp expressing cell line (A-172). Cytotoxicity studies demonstrated significantly low IC50 for both IMM-PLGA-NPs and IMM-PLGA-P84-NPs when compared with IC50 of IMM-S. IMM-PLGA-P84-NPs showed a significantly low IC50 against P-gp overexpressing cell lines when compared with IC50 of IMM-PLGA-NPs. In contrary, IMM-PLGA-NPs showed lower IC50 against non P-gp expressing cell line. This study demonstrated the feasibility of targeting surface decorated NPs to multidrug resistant gliomas. However, to address its clinical utility extensive in vivo studies are required.

Improved oral efficacy of epirubicin through polymeric nanoparticles: pharmacodynamic and toxicological investigations.

Epirubicin (EPI) elicits poor-oral bioavailability hence commercially available as injection for intravenous administration which follows a rapid increase and fast decay in plasma drug concentration often needs a frequent dosing that may lead to serious side effects. Aim of the present study is to develop a nanoparticulate system which could deliver epirubicin effectively via oral administration and could eventually promote new concept "chemotherapy at home." In this perspective, epirubicin loaded Poly-lactide-co-glycolic acid nanoparticles (EPI-NPs) were developed by double emulsion evaporation techniques and evaluated for its safety and efficacy against Ehrlich's Ascites (EAT) induced tumor in balb/c mice. In vivo fate of nanoparticles after oral administration in Albino wistar rats was also studied. EPI-NPs showed marked reduction in tumor size ∼40% while tumor size was increased 3.55 and 3.28 folds in control as well as in group treated orally with free epirubicin solution (EPI-S), respectively. Furthermore, toxicological evaluation demonstrated insignificant difference in levels of biomarkers including MDA, CAT, SOD, LDH, CK-MB, AST and ALT when EPI-NPs-oral treatment was compared with control group while levels of these biomarkers were found extremely significant in group treated with EPI-S (i.v). and demonstrated increment in LDH (p < 0.001), CK-MB (p < 0.001), AST (p < 0.001), ALT (p < 0.001) and MDA levels (p < 0.001) and reduction in SOD (p < 0.001) and CAT levels (p < 0.001) thus confirmed better safety profile of EPI-NPs oral than EPI-S i.v. Biodistribution study demonstrated the presence of NPs in different body organs and blood which suggests probability of NPs translocation across intestine thus at the tumor site.

Surface decorated nanoparticles as surrogate carriers for improved transport and absorption of epirubicin across the gastrointestinal tract: Pharmacokinetic and pharmacodynamic investigations.

Epirubicin (EPI) is a P-gp substrate antracycline analogue which elicits poor oral bioavailability. In the present work, EPI loaded poly-lactide-co-glycolic acid nanoparticles (PLGA-NPs) were prepared by double emulsion approach and superficially decorated with polyethylene glycol (EPI-PNPs) and mannosamine (EPI-MNPs). Average hydrodynamic particle size of EPI-PNPs and EPI-MNPs was found 248.63 ± 12.36 and 254.23 ± 15.16 nm, respectively. Cytotoxicity studies were performed against human breast adenocarcinoma cell lines (MCF-7) confirmed the superiority of EPI-PNPs and EPI-MNPs over free epirubicin solution (EPI-S). Further, confocal laser scanning microscopy (CLSM) and flow cytometric analysis (FACS) demonstrated enhanced drug uptake through EPI-PNPs and EPI-MNPs and elucidated dominance of caveolae mediated endocytosis for NPs uptake. Cellular transport conducted on human colon adenocarcinoma cell line (Caco-2) showed 2.45 and 3.17 folds higher permeability of EPI through EPI-PNPs and EPI-MNPs when compared with EPI-S (p<0.001) while permeability of EPI was found 5.23 and 5.67 folds higher across rat ileum, respectively. Furthermore, pharmacokinetic studies demonstrated 4.7 and 5.57 folds higher oral bioavailability through EPI-PNPs and EPI-MNPs when compared with EPI-S. In addition, both, EPI-PNPs and EMNPs showed tumor suppression comparable to indicated route (i.v. injection). EPI-MNPs showed 1.18 folds higher bioavailability and better tumor suppression than EPI-PNPs.