Externally triggered smart drug delivery system encapsulating idarubicin shows superior kinetics and enhances tumoral drug uptake and response.

Rationale: Increasing the bioavailable drug level in a tumor is the key to enhance efficacy of chemotherapy. Thermosensitive smart drug delivery systems (SDDS) in combination with local hyperthermia facilitate high local drug levels, thus improving uptake in the tumor. However, inability to rapidly and efficiently absorb the locally released drug results in reduced efficacy, as well as undesired redistribution of the drug away from the tumor to the system. Methods: Based on this paradigm we propose a novel approach in which we replaced doxorubicin (DXR), one of the classic drugs for nanocarrier-based delivery, with idarubicin (IDA), a hydrophobic anthracycline used solely in the free form for treatment hematologic cancers. We established a series of in vitro and in vivo experiments to in depth study the kinetics of SDDS-based delivery, drug release, intratumor biodistribution and subsequent cell uptake. Results: We demonstrate that IDA is taken up over 10 times more rapidly by cancer cells than DXR in vitro. Similar trend is observed in in vivo online imaging and less drug redistribution is shown for IDA, together resulting in 4-times higher whole tumor drug uptake for IDA vs. DXR. Together his yielded an improved intratumoral drug distribution for IDA-SDDS, translating into superior tumor response compared to DXR-SDDS treatment at the same dose. Thus, IDA - a drug that is not used for treatment of solid cancers - shows superior therapeutic index and better outcome when administered in externally triggered SDDS. Conclusions: We show that a shift in selection of chemotherapeutics is urgently needed, away from the classic drugs towards selection based on properties of a chemotherapeutic in context of the nanoparticle and delivery mode, to maximize the therapeutic efficacy.

Clinoptilolite Microparticles as Carriers of Catechin-Rich Acacia catechu Extracts: Microencapsulation and In Vitro Release Study.

The main goal of the present study was to investigate the microencapsulation, in vitro release capacity and efficiency of catechin-rich Acacia catechu extract by Clinosorbent-5 (CLS-5) microparticles by in-depth detailed analyses and mathematical modelling of the encapsulation and in vitro release kinetics behaviour of the polyphenol-mineral composite system. The bioflavanol encapsulation and release efficiency on/from the mineral matrix were assessed by sorption experiments and interpretative modelling of the experimental data. The surface and spectral characteristics of the natural bioactive substance and the inorganic microcarrier were determined by Fourier Transform Infrared Spectroscopy (FTIR) and Ultraviolet/Visible (UV/Vis) spectrophotometric analyses. The maximum extent of catechin microencapsulation in acidic medium was 32%. The in vitro release kinetics study in simulated enzyme-free gastric medium (pH = 1.2) approved 88% maximum release efficiency achieved after 24 h. The in vitro release profile displayed that the developed bioflavanol/clinoptilolite microcarrier system provided sustained catechin in vitro release behaviour without an initial burst effect. Thus, the results from the present study are essential for the design and development of innovative catechin-CLS-5 microcarrier systems for application in human and veterinary medicine.

Construction of Surface-Modified Polydopamine Nanoparticles for Sequential Drug Release and Combined Chemo-Photothermal Cancer Therapy.

Single chemotherapy often causes severe adverse effects and drug resistance to limit therapeutic efficacy. As a noninvasive approach, photothermal therapy (PTT) represents an attractive option for cancer therapy due to the benefits of remote control and precise treatment methods. Nanomedicines constructed with combined chemo-photothermal properties may exert synergistic effects and improved antitumor efficacy. In this study, we developed polydopamine (PDA)-coated nanoparticles grafted with folic acid (FA) and polyethylene glycol to transport doxorubicin (DOX) for targeted cancer therapy. The results showed that this delivery vehicle has a nanoscale particle size and narrow size distribution. No particle aggregation or significant drug leakage was observed during the stability test. This system presented excellent photothermal conversion capability under near-infrared light (NIR) laser irradiation due to the PDA layer covering. In vitro dissolution profiles demonstrated that sequential and triggered DOX release from nanoparticles was pH-, NIR irradiation-, and redox level-dependent and could be best fitted with the Ritger-Peppas equation. FA modification effectively promoted the intracellular uptake of nanoparticles by HepG2 cells and therefore significantly inhibited cell recovery and induced tumor cell apoptosis. Compared to the free DOX group, nanoparticles reduced the DOX concentration in the heart to avoid drug-related cardiotoxicity. More importantly, the in vivo antitumor efficacy results showed that compared with the single chemotherapy strategy, the nanoparticle group exerted combined and satisfactory tumor growth inhibition effects with good biocompatibility. In summary, this nanocarrier delivery system can organically combine chemotherapy and PTT to achieve effective and precise cancer treatment.

Evaluation of hyaluronic acid nanoparticle embedded chitosan-gelatin hydrogels for antibiotic release.

The development of chitosan-gelatin (CS-G) hydrogels embedded with ampicillin-loaded hyaluronic acid nanoparticles (HA-NPs) for wound dressing is proposed. It was aimed to provide controlled ampicillin delivery by incorporation of HA-NPs into biocompatible CS-G hydrogel structure. According to in vitro ampicillin release studies, 55% of ampicillin was released from CS-G/HA-NPs hydrogels after 5 days. Antibacterial performance of CS-G/HA-NPs hydrogels was proven with agar disc diffusion test. For cytotoxicity assay, fibroblast cell viability increased in CS-G/HA-NPs hydrogels compared with CS-G group after 24 hr incubation. Consequently, the potential ability of CS-G/HA-NPs hydrogels as a controlled drug delivery system has been verified.

Folic Acid-Modified Erythrocyte Membrane Loading Dual Drug for Targeted and Chemo-Photothermal Synergistic Cancer Therapy.

To overcome the challenges of systemic toxicity and weak tumor selectivity caused by traditional antitumor drugs, numerous nanocarrier systems have been developed in recent decades, and their therapeutic effect has been improved to varying degrees. However, because of the drug resistance effect and metastasis involved in tumor recurrence, a single chemotherapy can no longer satisfy the diversified treatment needs. Recently, the application of chemotherapy in combination with thermotherapy as a synergistic approach has been proven to be more effective, and it provides a new strategy for cancer therapy. In this work, by utilizing the unique properties of erythrocytes, a surface-modified erythrocyte membrane was constructed as a novel nanocarrier system (DOX and ICG-PLGA@RBC nanoparticles, DIRNPs for short) for the simultaneous transportation of chemotherapeutic drugs (doxorubicin, DOX) and photothermal agents (indocyanine green, ICG) to achieve the effects of long-term circulation, active tumor targeting, and triggered drug release. The results indicated that DIRNPs have a nanoscale particle size of 158.4 nm with a narrow size distribution and a negative surface charge of -5.79 mV. No particle aggregation or remarkable drug leakage was observed during the 30 day storage test, and because of the excellent photothermal conversion ability of ICG, the local temperature of DIRNPs could dramatically increase from 33.7 to 49.8 °C in 10 min under near-infrared (NIR) laser irradiation. The in vitro drug dissolution data demonstrated that the DOX release from the DIRNPs was pH-dependent and NIR-triggered. Folic acid modifications of the erythrocyte membrane effectively facilitated the intracellular uptake of DIRNPs by HepG2 cells and, as a result, it significantly inhibited tumor cell growth, promoted reactive oxygen species levels, induced cell apoptosis, and restricted cell recovery and migration. In vivo pharmacokinetics and biodistribution studies indicated that the DIRNPs prolonged the half-life of DOX from 6.03 to 17.6 h and remarkably reduced the DOX level in the heart to avoid drug-related cardiotoxicity. More importantly, the DIRNPs exerted excellent in vivo antitumor efficacy against H22 tumors with superior safety. In conclusion, utilizing the advantageous properties of erythrocytes to construct a tumor-targeted biomimetic nanocarrier for codelivery of chemotherapeutics and photothermal agents to produce synergistic effects is considered an effective method for cancer therapy.

Formulation and evaluation of niosomal vesicles containing ondansetron HCL for trans-mucosal nasal drug delivery.

Ondansetron HCl is a (5-HT3) serotonin receptor antagonist, used as anti-emetic drug in combination with anticancer agents. Conventional dosage forms have poor bioavailability and patient compliance. These problems can be reduced by the use of nasal niosomal thermo-reversible in situ gelling system. Niosomes were formulated using various surfactants (Span 60, Span 80, Tween 20, and Tween 80) in different ratios using the thin-film hydration technique. Niosomes were evaluated for particle size, zeta potential, transmission electron microscopy (TEM) imaging, drug entrapment efficiency, and in vitro drug release. Niosomes prepared using Span 60 and cholesterol in the ratio 1:1 (F5) showed higher entrapment efficiency (76.13 ± 1.2%) and in vitro drug release (91.76%) after 12 h was optimized. The optimized niosomes were developed into thermo-reversible in situ gel, composed of Poloxamer 407 and sodium carboxymethyl cellulose, prepared by cold method technique. Compatibility study (FTIR, DSC) was made for drugs and excipients that showed no significant interaction. The gel formulation G5 showed the most suitable gelation temperature (31 °C), viscosity (1250 mpoise), bioadhesion force (5860 ± 28 dyne/cm2), and in vitro drug release (70.6%) after 12 h. Comparative in vivo pharmacokinetic study on rabbits showed a sustained release and higher relative bioavailability of the prepared nasal in situ gel compared to similar dose of oral tablets (202.4%) which make ondansetron HCl niosomal nasal thermo-sensitive in situ gel a more convenient dosage form for the administration of ondansetron HCl than oral tablets.

A metal-phenolic network-based multifunctional nanocomposite with pH-responsive ROS generation and drug release for synergistic chemodynamic/photothermal/chemo-therapy.

Developing multifunctional nanomaterials with chemodynamic therapy (CDT)-based combination therapy has increasingly become a promising strategy for cancer treatment. Herein, a metal-phenolic network-based multifunctional nanocomposite (PID@Fe-TA) via the noncovalent interaction of multiple nontoxic raw materials has been designed to integrate the synergistic effect of CDT, photothermal therapy (PTT) and chemotherapy into one nanoplatform for breast cancer treatment. Benefiting from the pH-responsive properties and the assistance of near infrared (NIR) laser irradiation, the outer shell Fe3+-tannic acid (TA) complexes of PID@Fe-TA can be easily degraded into Fe3+ and TA as well as to release chemotherapeutic drugs (doxorubicin, DOX) and photothermal transforming agents (indocyanine green, ICG) in a tumor microenvironment (TME) or cancer cells. The released TA can accelerate the reduction of Fe3+ to Fe2+ for ensuring effective conversion of hydrogen peroxide (H2O2) into a highly toxic hydroxyl radical (˙OH) via the Fenton reaction. The exposed DOX can enter the cell nucleus to induce chemotherapy. The released ICG can locate the distribution of nanocomposites in the body. Besides, the heat generated from PID@Fe-TA after NIR laser irradiation can further promote the therapeutic effect of PPT-enhanced CDT. Importantly, an excellent therapeutic efficacy is achieved both in in vitro and in vivo via the CDT/PTT/chemotherapy combination based on this "all-in-one" nanoplatform, providing a good paradigm for effective cancer eradication.

Novel pH-sensitive alginate hydrogel delivery system reinforced with gum tragacanth for intestinal targeting of nutraceuticals.

The present study utilizes the novel combination of Gum tragacanth (GT) and sodium alginate (SA) to reinforce SA hydrogel beads. The composite hydrogel beads were encapsulated with phenolic compounds extracted from Basella sps. The rheological studies conferred increased elastic property of GT incorporated formulations. Higher swelling behavior was observed in simulated intestinal fluid (SIF) with increasing GT content in SA formulations. SA-GT composite hydrogels revealed increased encapsulation efficiency with sustained release of phenolic compounds in SIF. GT incorporated hydrogel beads exhibited increased biodegradation (up to 82% weight loss) in biodegradation media (in vitro). FTIR study found no molecular interaction between SA and GT. TGA analysis revealed that GT incorporation did not affect the thermal behavior of SA. Furthermore, SA-GT encapsulated hydrogels showed remarkable cytotoxicity against osteosarcoma cells. Thus our findings suggest SA-GT gel formulation could be used as a promising delivery system for drugs and nutraceutical compounds.

Mucoadhesive films based on gellan gum/pectin blends as potential platform for buccal drug delivery.

Films of gellan gum:pectin blends were prepared by solvent casting method. Gellan gum:pectin mass ratios were varied (4:1; 1:1; 1:4) at different concentrations (3% or 4%) and glycerol was used as plasticizer (1 or 2%). The films were thin (18-30 µm), translucent, flexible, and homogeneous. The surface pH was suitable for buccal application. All films reached high mechanical resistance and the mucoadhesive ability of them was evidenced. High ratio of gellan gum improved the mechanical resistance and the mucoadhesion of the films as well as the control of drug release rates. The films did not disintegrate in simulate saliva up to 24 h and curcumin release could be sustained up to 12 h. The set of data evidence that the films designed in this work represent a potential platform for buccal drug delivery.

Cross-linked pH-sensitive pectin and acrylic acid based hydrogels for controlled delivery of metformin.

The purpose of present study is to load Metformin HCl into pH-sensitive hydrogels to have sustained release over a period of time. The hydrogel was synthesized from naturally occurring polysaccharide pectin and monomer acrylic acid (AA) using ethylene glycol dimethacrylate (EGDMA) as cross-linker under controlled conditions for polymerization at 45°C for one hr, 50°C for two hrs, 55°C for three hrs, 60°C for four hrs and finally 65˚C for 12 hrs. Hydrogels were characterized for dynamic/equilibrium swelling, sol-gel fraction analysis, diffusion coefficient and percentage porosity. Hydrogels were tested by FTIR, XRD and SEM for structure and surface morphology respectively. Experimental in-vitro drug release data was applied to kinetic models. Formation of strong bonding between pectin and AA was supported by FTIR. The intensity of XRD peaks was reduced in non-loaded and loaded hydrogels compared to active drug substance. The non-loaded hydrogel showed discrete porous structure whereas loaded hydrogels were fibrous and smooth. Hydrogels showed higher swelling in the solutions of pH 6.5 and 7.5 as compared to in the solutions of pH 1.2 and 5.5. The diffusion coefficient decreases with the increase of AA and pectin concentrations. It was observed upon increasing the EGDMA concentration porosity decreases. The release of drug from all compositions of hydrogels took place through non-Fickian diffusion mechanism.

A near-infrared light-controlled smart nanocarrier with reversible polypeptide-engineered valve for targeted fluorescence-photoacoustic bimodal imaging-guided chemo-photothermal therapy.

Despite burgeoning development of nanoplatform made in the past few years, it remains a challenge to produce drug nanocarrier that enables requested on/off drug release. Thus, this study aimed to develop an ideal near-infrared light-triggered smart nanocarrier for targeted imaging-guided treatment of cancer that tactfully integrated photothermal therapy with chemotherapy to accurately control drug release time and dosage. Methods: This delivery system was composed of Ag2S QD coating with dendritic mesoporous silica (DMSN), which acted as nanocarrier of doxorubicin localized inside pores. To provide the nanocarrier with controlled release capability, a polypeptide-engineered that structure was reversible to photothermal effect of Ag2S QD, was covalently grafted to the external surface of drug-loaded DMSN. Results: This nanocarrier with the size of 40~60 nm had satisfactory biocompatibility and photothermal conversion efficiency up to 28.35%. Due to acidity-triggered charge reversal of polypeptide, which significantly extended circulation time and improved targeting ability, fluorescence and photoacoustic signals were still obvious at tumor site post-24 h by tail vein injection and chemo-photothermal synergistic therapy obviously enhanced antitumor efficacy. Mild PTT with multiple short-term exposures not only reduced the side effect of overdose drug but also avoided skin damage caused by long-term irradiation. Conclusion: By adjusting irradiation time and on/off cycle, multiple small amount local drug release reduced the side effect of overdose drug and skin damage. This novel approach provided an ideal near-infrared light-triggered nanocarrier with accurate control of area, time, and especially dosage.

NIR-Triggered Multifunctional and Degradable Nanoplatform Based on an ROS-Sensitive Block Copolymer for Imaging-Guided Chemo-Phototherapy.

Imaging-guided chemo-phototherapy based on multifunctional nanocarriers has emerged as a promising and high-efficient cancer treatment because of the inevitable limitations of single therapy. Herein, a near-infrared (NIR) light-activated degradable polymeric nanoplatform was fabricated for chemo-phototherapy. An NIR photosensitizer, IR780, and a chemotherapeutic drug, doxorubicin (DOX), were efficiently coloaded within a reactive oxygen species (ROS)-sensitive polymeric micelle based on an amphiphilic copolymer with degradable thioketal (TK) linkages. The obtained spherical nanoparticles (denoted as (IR780/DOX)@PTK) exhibited a notable photodynamic and photothermal effect upon NIR light exposure. Furthermore, due to the rapid cleavage of TK linkers induced by ROS generated from NIR-activated IR780, (IR780/DOX)@PTK also showed an NIR light-induced degradable feature, which can be used for light-triggered tumor-specific drug release and lead to ignorable systematic toxicity after biodegradation and drug delivery. Under the guidance of NIR fluorescence and photothermal dual modal imaging, (IR780/DOX)@PTK exhibited excellent tumor accumulation after intravenously injection into 4T1-tumor-bearing mice. As verified in both in vitro and in vivo study, (IR780/DOX)@PTK presented a significant tumor suppression effect by synergistic chemo-phototherapy.

PEGylated graphene oxide-capped gold nanorods/silica nanoparticles as multifunctional drug delivery platform with enhanced near-infrared responsiveness.

In this paper, near infrared (NIR)-responsive core-shell gold nanorods/mesoporous silica nanoparticles capped with PEGylated graphene oxide (GNRs/SiO2/GO-PEG) were prepared via electrostatic and physical absorption interactions. Hybrid nanoparticles display distinct photothermal stability in physiological environment and acidic media because of the introduction of biocompatible GO-PEG. In addition, due to the high specific surface area of GO-PEG and synergistically enhanced photothermal effect between GO-PEG and GNRs, GNRs/SiO2/GO-PEG nanoparticles exhibit excellent drug loading efficiency and superior photothermal conversion efficiency (39.53%). More importantly, significant pH-/NIR- dual responsive drug release upon NIR irradiation could be observed from GNRs/SiO2/GO-PEG nanoparticles due to the π-π cooperative interaction between GO-PEG and doxorubicin hydrochloride (DOX), and synergistically enhanced NIR-responsiveness derived from GNRs/GO-PEG. The present paper furnishes a green and feasible method to prepare smart core/shell hybrid nanoparticles with high drug loading efficiency and excellent photothermal conversion efficiency, which possess great perspectives as a multifunctional platform for remotely controllable drug delivery.

Albumin-bioinspired iridium oxide nanoplatform with high photothermal conversion efficiency for synergistic chemo-photothermal of osteosarcoma.

Protein-based nanocarriers with inherent biocompatibility have been widely served as building blocks to construct versatile therapeutic nanoplatforms. Herein, bovine serum albumin-iridium oxide nanoparticles (denoted BSA-IrO2 NPs) are successfully synthesized via one-step biomineralization approach. The BSA-IrO2 NPs exhibits uniform size (40 nm), superb biocompatibility and high drug loading capacity for doxorubicin (27.4 wt%). Under near-infrared (NIR) laser irradiation, the as-prepared BSA-IrO2 NPs exhibited high photothermal conversion ability (54.3%) and good photostability. The in vitro drug release experiments displayed pH and NIR laser -triggered DOX release profiles, which could enhance the therapeutic anticancer effect. By utilizing this DOX loaded nanoplatform, effective synergistic chemo-photothermal therapy against human osteosarcoma can be realized, which has been systematically verified both in vitro and in vivo. Notably, in vivo pharmacokinetics studies showed that BSA-IrO2@DOX had prolonged blood circulation time due to the BSA component can improve the stealthiness of the nanoparticles during the blood circulation. Meanwhile, in vitro and in vivo toxicity studies demonstrated that the BSA-IrO2 NPs can act as biocompatible agents for drug delivery and cancer therapy. Therefore, this work presents a biomineralized iridium-based NPs with remarkable features and be used as a very potential therapeutic nanoplatform for cancer treatment.

Nanoscale Hybrid Coating Enables Multifunctional Tissue Scaffold for Potential Multimodal Therapeutic Applications.

Through a nature-inspired layer-by-layer assembly process, we developed a unique multifunctional tissue scaffold that consists of porous polyurethane substrate and nanoscale chitosan/graphene oxide hybrid coating. Alternative layers of drug-laden chitosan and graphene oxide nanosheets were held together through strong electrostatic interaction, giving rise to a robust multilayer architecture with control over structural element orientation and chemical composition at nanoscale. Combined pH-controlled co-delivery of multiple therapeutic agents and photothermal therapy has been achieved by our scaffold system. The new platform technology can be generalized to produce other tissue scaffold systems and may enable potential multimodal therapeutic applications such as bone cancer managements.

Design of selegiline-loaded bio-nanosuspension for the management of depression using novel bio-retardant from Manilkara zapota.

Objective: Depression is one of the most frequent psychiatric and potentially life-threatening disorders. This research work can offer a potential for delivery of selegiline moiety via ocular route in bio-nanosuspension mode for the effective management of depression after preclinical performance screening. Methods: The selegiline-loaded bio-nanosuspension was prepared using novel bio-retardant isolated from fruit pulp of Manilkara zapota (Sapodilla) by sonication solvent evaporation method with different ratios (0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, and 1%) and with standard polymer HPMC (0.1%, 0.2%, 0.3%, 0.4%, and 0.5%). The prepared formulations were evaluated for pH stability studies, %entrapment efficiency, in vitro drug release, particle size, polydispersity index (PDI), zeta potential, and stability studies. Results: The prepared bio-nanosuspension was subjected to the best formulation based on comparison of above-mentioned evaluation parameters, so Fb2 (0.1%) formulation was found to be the best formulation showing an R2 value of 0.9814, T50% of 29.7 h, and T80% of 65.25 h. According to the release kinetics, the best fit model was found to be the Korsmeyer-Peppas with the Fickian diffusion (Higuchi matrix) as the mechanism of drug release. Manilkara zapota (Sapodilla) provided excellent stability for the formulation and resulting particle size for the best formulation was found to be 252 nm. The bio-nanosuspension had PDI of 0.35 with zeta potential of -8.91 mV. Conclusion: The prepared bio-nanosuspension was found to be safe and compatible with the ophthalmic delivery for treatment of depression.

Preparation and Evaluation of Mosapride Citrate Dual-Release Dry Suspension.

In this paper, a novel formulation of dual-release dry suspension of mosapride citrate (DRDS-MC) was designed which can be quickly released in the stomach while having sustained-release effect. Co-grinding mixture of mosapride citrate (MC) together with L-HPC as hydrophilic excipient was prepared in order to improve the solubility of MC. The co-grinding mixture was characterized by solubility studies, DSC, X-RD, SEM, FTIR, and size distribution before the preparation of the DRDS-MC. Then, the co-grinding mixture was used to prepare DRDS-MC via wet granulation method. The evaluation of DRDS-MC was focused on physicochemical properties, intestinal absorption, and pharmacokinetics. The results of DSC, X-RD, SEM, FTIR, and size distribution indicated that MC resides in co-grinding mixture with no crystalline changes, hydrogen bonds made L-HPC greatly improving the solubility of MC. Then, the dissolution of DRDS-MC reached 70% in pH 1.2 within 2 h, and the 12-h dissolution of MC in pH 6.8 was nearly 80%. The sedimentation volume after 3 h was 0.94 and redispersibility was good. The linear regression equation between in vitro release of DRDS-MC and intestinal absorption fraction in rats was: Y = 29.215 + 47.535*X (r = 0.952). At last, pharmacokinetic studies in beagle dogs demonstrated that DRDS-MC has prolonged effect compared with commercial formulation Gasmotin as a reference. All results indicated that the DRDS-MC could be quickly released in the stomach while having sustained-release effect.

Clove oil based co-surfactant free microemulsion of flurbiprofen: Improved solubility with ameliorated drug-induced gastritis.

Flurbiprofen, an NSAID, is a water insoluble drug that is also notorious for gastric irritation and inflammation. This study was aimed at using a natural gastrprotective oil as the internal phase to develop flurbiprofen micro emulsion (ME) to improve it solubility and ameliorate its gastric side effects. Upon screening of ME components for drug solubility, clove oil, tween 80 and transcutol were identified as the oil, surfactant and co surfactant, respectively, with higher flurbiprofen solubility. Pseudo-ternary phase diagrams revealed that the ME made with surfactant only and without co-surfactant displayed the similar ME region as made with the mixture of surfactant and co-surfactant. Furthermore, drug loaded oil was also used to draw pseudo-ternary phase diagram and a very little decrease in the ME region was observed. Therefore, co-surfactant free flurbiprofen loaded ME was developed to avoid side effects associated with the use of excessive surfactant quantities. ME were found to possess size in the range of 11-41 nm with PDI <0.5 and a slightly negative charge. Conductivity, pH and refractive indices of the selected MEs were well in the range. Drug release studies indicated maximum drug release from MEs within 5 min. Analysis of the gastric mucosa of rats after oral administration of drug solution and drug loaded ME confirmed that clove oil based ME provided significant protection against the NSAIDs induced gastric damage.

Preparation and Characterization of Resveratrol Loaded Pectin/Alginate Blend Gastro-Resistant Microparticles.

BACKGROUND: The use of resveratrol as a dietary supplement is limited because it is easily oxidized and, after oral ingestion, it is metabolized into enterocytes and hepatocytes. Thus, new formulations are needed in order to improve its oral bioavailability. OBJECTIVE: The objective of this study was to develop and characterize a gastro-resistant formulation of resveratrol for oral administration as a dietary supplement. METHOD: Resveratrol was encapsulated in Eudragit-coated pectin-alginate microparticles. RESULTS: The microparticle size was about 1450 µm, with an encapsulation efficiency of 41.72% ± 1.92%. The dissolution assay conducted, as specified in the European Pharmacopoeia for delayed-release dosage forms, revealed that our microparticles were gastro-resistant, because the resveratrol percentage released from microparticles in acid medium was less than 10%. In addition, the high-performance liquid chromatographic (HPLC) method developed for resveratrol content quantification in the microparticles was validated according to International Council for Harmonisation (ICH) Q2 (R1) guidelines. Finally, the biological activity of resveratrol was investigated in 3T3-L1 mature adipocytes, concluding that the encapsulation process does not affect the activity of resveratrol. CONCLUSION: In summary, the gastro-resistant microparticles developed could represent a suitable method of including resveratrol in dietary supplements and in functional foods used in obesity therapy.

Development, optimization and evaluation of curcumin loaded biodegradable crosslinked gelatin film for the effective treatment of periodontitis.

OBJECTIVE: Aim of the present study was to prepare curcumin (CUR) loaded biodegradable crosslinked gelatin (GE) film to alleviate the existing shortcomings in the treatment of periodontitis. SIGNIFICANCE: Gelatin film was optimized to provide anticipated mucoadhesive strength, mechanical properties, folding endurance, and prolonged drug release over treatment duration, for successful application in the periodontitis. METHODS: The film was developed by using solvent casting technique and "Design of Experiments" approach was employed for evaluating the influence of independent variables on dependent response variables. Solid-state characterization of the film was performed by FTIR, XRD, and SEM. Further, prepared formulations were evaluated for drug content uniformity, surface pH, folding endurance, swelling index, mechanical strength, mucoadhesive strength, in vitro biodegradation, and in vitro drug release behavior. RESULTS: Solid state characterization of the formulation showed that CUR is physico-chemically compatible with other excipients and CUR was entrapped in an amorphous form inside the smooth and uniform film. The optimized film showed degree of crosslinking 51.04 ± 2.4, swelling index 138.10 ± 1.25, and folding endurance 270 ± 3 with surface pH around 7.0. Crosslinker concentrations positively affected swelling index and biodegradation of film due to altered matrix density of the polymer. Results of in vitro drug release demonstrated the capability of the developed film for efficiently delivering CUR in a sustained manner up to 7 days. CONCLUSIONS: The developed optimized film could be considered as a promising delivery strategy to administer medicament locally into the periodontal pockets for the safe and efficient management of periodontitis.