Emulsification Diffusion Research Articles

Microencapsulation of rifampicin for the prevention of endophthalmitis: In vitro release studies and antibacterial assessment

Rifampicin encapsulated microparticles were designed for intraocular injection after cataract surgery to prevent postoperative endophthalmitis. Microparticles were formulated by emulsification diffusion method using poly(lactic acid-co-glycolic acid) (PLGA) as polymer in order to propose a new form of rifampicin that overcome its limitations in intraocular delivery. Depending on processing formulation, different types of microparticles were prepared, characterized and evaluated by in vitro release studies. Two types of microparticles were selected to get a burst release of rifampicin, to reach minimal inhibitory concentrations to inhibit 90% of Staphylococcus epidermidis mainly involved in postoperative endophthalmitis, combined with a sustained release to maintain rifampicin concentration over 24h. The antibacterial activity and antiadhesive property on intraocular lenses were evaluated on S. epidermidis. Microparticles, with a rapid rifampicin release profile, showed an effect towards bacteria development similar to free rifampicin over 48h. However, slow-release profile microparticles exhibited a similar antibacterial effect during the first 24h, and were able to destroy all the S epidermidis in the medium after 30h. The association of the two formulations allowed obtaining interesting antibacterial profile. Moreover, rifampicin-loaded microparticles have shown a very efficient anti-adherent effect of S. epidermidis on intraocular lenses at 24h. These results propose rifampicin microparticles as suitable for antibioprophylaxis of the postoperative endophthalmitis.

Development and assessment of kerateine nanoparticles for use as a hemostatic agent

Uncontrolled bleeding frequently occurs in some emergencies which can result in severe injury and even death. Keratin hydrogel has been found that it had good ahemostatic efficacy in the previous studies. However, an ideal hemostatic agent should not require mixing or preparation in advance, and hydrogel is not easy to store and carry. In the present study, the kerateine was firstly extracted from human hair, and then was prepared nanoparticles by a modified emulsion diffusion method. The synthesized nanoparticles showed spherical morphology with an average diameter of approximately 200nm. The results of Fourier transform infrared spectroscopy and X-ray diffraction indicated that the chemical structure of kerateine did not change but the crystal form may be transformed in the nanoparticles. In addition, kerateine nanoparticles displayed a faster clotting time in vitro study than the kerateine extracts. Furthermore, kerateine nanoparticles significantly reduced the blood loss and coagulation time in the liver puncture and tail amputation in rat models. Our results indicated that kerateine nanoparticles could quickly form a high viscosity gel onto the wound and accelerate the blood coagulation based on their high specific surface area. Therefore, kerateine nanoparticles have great potential for hemostatic application.

Treatment of bleomycin-induced pulmonary fibrosis by inhaled tacrolimus-loaded chitosan-coated poly(lactic-co-glycolic acid) nanoparticles.

Pulmonary fibrosis is a chronic lung disease characterized by inflammation and collagen deposition, with an estimated mortality rate exceeding 70%. Here, we evaluated the therapeutic effectiveness of inhaled tacrolimus-loaded chitosan-coated poly(lactic-co-glycolic acid) nanoparticles (chitosan TAC PLGA-NPs) in a bleomycin-induced pulmonary fibrosis mouse model. Chitosan TAC PLGA-NPs were fabricated using an o/w emulsification diffusion method, and uncoated TAC PLGA-NPs and chitosan TAC PLGA-NPs were spherical with approximate diameters of 320 and 441 nm, respectively. The zeta potential of chitosan TAC PLGA-NPs (+13.6 mV) was increased significantly by chitosan-coating versus uncoated TAC PLGA-NPs (-28.3 mV). The incorporation efficiency of tacrolimus was 37.7%, and the tacrolimus was gradually released until about 5 day. Direct inhalation of chitosan TAC PLGA-NPs (TAC 180 μg/mouse) twice a week produced marked anti-fibrotic efficacy in mice with bleomycin-induced pulmonary fibrosis, which was much better than the efficacy resulting from daily oral administration (TAC 300 μg/mouse) on the basis of hematoxylin/eosin and Masson's trichrome staining assessments. Imaging of lung deposition showed that chitosan TAC PLGA-NPs were located well in the lungs and gradually faded over 96 h. The pulmonary delivery of tacrolimus could be therapeutically efficacious for treating pulmonary fibrosis. TAC-loaded PLGA nanoparticles should be considered to be an efficient sustained-release type inhalation system that reduces administration frequency and relevant side effects.

Drug nanoparticles by emulsion-freeze-drying via the employment of branched block copolymer nanoparticles

A large percentage of drug compounds exhibit low water solubility and hence low bioavailability and therapeutic efficacy. This may be addressed by preparation of drug nanoparticles, leading to enhanced dissolution rate and direct use for treatment. Various methods have been developed to produce drug nanocrystals, including wet milling, homogenization, solution precipitation, emulsion diffusion, and the recently developed emulsion freeze-drying. The drawback for these methods may include difficult control in particles size, use of surfactants & polymer, and low ratio of drug to stabilizer. Here, biocompatible branched block copolymer nanoparticles with lightly-crosslinked hydrophobic core and hydrophilic surface groups are synthesized by the direct monomer-to-particle methodology, characterized, and then used as scaffold polymer/surfactant to produce drug nanoparticles via the emulsion-freeze-drying approach. This method can be used for model organic dye and different poorly water-soluble drugs. Aqueous drug nanoparticle dispersions can be obtained with high ratio of drug to stabilizer and relatively uniform nanoparticle sizes.

Melatonin releasing PLGA micro/nanoparticles and their effect on osteosarcoma cells

Melatonin loaded poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles and microparticles in the diameter of ∼200 nm and 3.5 μm, respectively, were prepared by emulsion–diffusion–evaporation method. Melatonin entrapment into the particles was significantly improved with the addition of 0.2% (w/v) melatonin into the aqueous phase and encapsulation efficiencies were found as 14 and 27% for nanoparticles and microparticles, respectively. At the end of 40 days, ∼70% of melatonin was released from both of particles, with high burst release. Both blank and melatonin loaded PLGA nanoparticles caused toxic effect on the MG-63 cells due to their uptake by the cells. However, when 0.05 mg microparticle that is carrying ∼1.7 μg melatonin was added to the cm2 of culture, inhibitory effect of melatonin on the cells were obviously observed. The results would provide an expectation about the usage of melatonin as an adjunct to the routine chemotherapy of osteosarcoma by encapsulating it into a polymeric carrier system.

Co-delivery of siRNA and hypericin into cancer cells by hyaluronic acid modified PLGA-PEI nanoparticles

Context: Malignant tumors cause more death because of the resistance of the hypoxic cancer cell toward radiotherapy. Targeting for hypoxic cancer area and gene silencing to overcome the hypoxia are two kinds of important therapeutic strategies for treating tumors.Objective: In order to explore the combined effects of gene therapy and hypericin (Hy) on tumor cells, hypoxia-inducible factor 1 alpha (HIF-1α) small interfering ribonucleic acid (siRNA) was transfected into the hypoxic human nasopharyngeal carcinoma (CNE2) cells using Hy-encapsulated nanocomplexes (Hy-HPP NPs) as a carrier which would achieve dual targeting to the tumor necrosis area.Materials and methods: NPs were prepared by emulsion–diffusion–evaporation method. Formulations were evaluated by conducting in vitro physicochemical studies, electrophoresis, in vivo study, and biochemical studies.Results and discussions: Hy-loaded nanoparticles with a mean size of around 160 nm was able to enhance the accumulation in the tumors by enhanced permeability and retention effect. The electrophoresis confirmed the good stability of siRNA/Hy-HPP NPs in the presence of phosphate-buffered saline (pH 7.4), competitive heparin, and RNase. The results of transfection showed that the uptake of siRNA was significantly increased up to 50% in CNE2 cells. The level of the HIF-1α with Hy-encapsulated nanocomplexes was significantly reduced to 30% in the transfected CNE2 cells. In vivo studies, the carrier exhibited higher intensity at the tumor tissue cells and higher affinity toward the necrotic tumor tissue.Conclusion: Results demonstrated that Hy-HPP NPs could significantly enhance the tranfection efficiency of siRNA, suggesting Hy-encapsulated nanoparticle as an efficient gene carrier. The co-delivery of HIF-1α siRNA (siHIF-1α) and Hy could efficiently decrease the level of HIF-1α and increase the affinity toward necrotic tissues. Hence, this is a promising strategy for further application in radiotherapy.

Temperature-responsive polymeric nanospheres containing methotrexate and gold nanoparticles: A multi-drug system for theranostic in rheumatoid arthritis

Inflammation plays a crucial role in rheumatoid arthritis progress. In the present work, a novel stealth polymeric nanospheres platform able to carry anti-inflammatory drugs and an imaging agent was developed. Incorporation of gold nanoparticles will allow photoacoustic imaging and near infra-red photothermal application. Through emulsion–diffusion evaporation technique methotrexate and gold nanoparticles were incorporated in the pegylated-poly(dl-lactic-co-glycolic acid) nanospheres. In vitro drug release assays revealed pH and temperature-dependence on gold nanoparticles. Blank nanospheres exhibited negligible in vitro cytotoxicity, while methotrexate-loaded nanospheres hampered monocytes and macrophages viability at a higher level than free methotrexate. Confocal fluorescent microscopy and flow cytometry revealed effective nanospheres internalization, and that their cellular uptake was energy dependent mediated by caveolae and clathrin-endocytosis mechanism. Finally, MTX-loaded multifunctional nanospheres containing gold lead to a significant reduction of IL-1β, IL-6 and TNF-α inflammatory cytokines produced by monocytes and macrophages upon in vitro inflammatory stimulation, suggesting a favorable anti-inflammatory activity. These results confirm that the multifunctional nanospheres represent a promising theranostic platform for RA diagnosis and intracellular treatment, by combining methotrexate and gold nanoparticles for a highly effective targeted chemo-photothermal therapy.

Preparation and Characterization of Poly L-Lactide/Triclosan Nanoparticles for Specific Antibacterial and Medical Applications

This work aims at preparation of poly-L-lactide (PLLA)/triclosan nanoparticles as antibacterial products used in some specific medical applications. PLLA was synthesized by the reaction extrusion via the ring opening polymerization of L-lactide using a continuous single-stage process, which is a fast and easy method. The PLLA triclosan nanoparticles were prepared by the emulsification–diffusion process with few modifications. Chloroform was used for the surface reaction of triclosan without any chemical shifts. The resulting nanoparticles with various triclosan quantities were fully characterized. The release as well as its kinetics was studied using the UV-visible spectroscopy. All the results confirmed the high stability and process efficiency of molecular dispersion and attachment of triclosan to PLLA. The sample containing 30% triclosan showed the best form among the others with the highest encapsulation efficiency. The synthesized nanoparticles with the controlled antibacterial activity could be considered as an appropriate alternative for application as antibacterial agent in the implantable surgical products as well as the drug delivery and wound-dressing applications.

Haloperidol Loaded Solid Lipid Nanoparticles for Nose to Brain Delivery: Stability and In vivo Studies

In the present study, Haloperidol loaded solid lipid nanoparticles were prepared to enhance its uptake to brain via intranasal route. SLNs were prepared by modified emulsification diffusion technique. For optimization, a three factors and three levels Box - Behnken design was applied to study the effect of independent variables (factors) i.e. drug to lipid ratio (A), surfactant concentration (B) and stirring speed (C) on dependent variables (responses) i.e. particles size (Y1), entrapment efficiency (Y2), and drug loading (Y3). The value of optimized variables for HP-SLNs was 1:2 (drug to lipid ratio), 1.625% (surfactant concentration) and 3000 rpm (stirring speed). The optimized HP-SLNs formulation was evaluated for stability and in vivo studies. Stability studies revealed no significant (P<0.5) change was observed in particle size, zeta potential, entrapment efficiency and drug loading of optimized HP-SLNs formulation when it was stored at 4 ± 2°C (refrigerator) and 25 ± 2°C/60 ± 5% RH up to six months, but the size of particles was increased significantly (P<0.001) when the optimized formulation was stored at 40 ± 2°C/75 ± 5% RH. A significant drop (P<0.001) in zeta potential was also observed at 40 ± 2°C/75 ± 5% RH after 3 months. In vivo studies were performed on albino Wistar rats and various pharmacokinetic and brain targeting parameters were determined. The pharmacokinetic parameters in brain after i.n. administration of HP-SLNs were found to be, Tmax 2 h, Cmax 329.17 ± 20.89 ng/mL, AUC0 - ∞ 2389.17 ± 78.82 ng.h/mL, Ke 0.079 ± 0.0065 h-1 and MRT 12.60 ± 0.99 h. The value of brain targeting parameters like drug targeting index, drug targeting efficiency and nose to brain direct transport were found to be 23.62, 2362.43% and 95.77% and 11.28, 1128.61% and 91.14% for HP-SLNs i.n. and HP Sol i.n. respectively.

Solid lipid nanoparticles for nose to brain delivery of haloperidol: in vitro drug release and pharmacokinetics evaluation

In the present study, haloperidol (HP)-loaded solid lipid nanoparticles (SLNs) were prepared to enhance the uptake of HP to brain via intranasal (i.n.) delivery. SLNs were prepared by a modified emulsification–diffusion technique and evaluated for particle size, zeta potential, drug entrapment efficiency, in vitro drug release, and stability. All parameters were found to be in an acceptable range. In vitro drug release was found to be 94.16±4.78% after 24h and was fitted to the Higuchi model with a very high correlation coefficient (R2=0.9941). Pharmacokinetics studies were performed on albino Wistar rats and the concentration of HP in brain and blood was measured by high performance liquid chromatography. The brain/blood ratio at 0.5h for HP-SLNs i.n., HP sol. i.n. and HP sol. i.v. was 1.61, 0.17 and 0.031, respectively, indicating direct nose-to-brain transport, bypassing the blood–brain barrier. The maximum concentration (Cmax) in brain achieved from i.n. administration of HP-SLNs (329.17±20.89ng/mL, Tmax 2h) was significantly higher than that achieved after i.v. (76.95±7.62ng/mL, Tmax 1h), and i.n. (90.13±6.28ng/mL, Tmax 2h) administration of HP sol. The highest drug-targeting efficiency (2362.43%) and direct transport percentage (95.77%) was found with HP-SLNs as compared to the other formulations. Higher DTE (%) and DTP (%) suggest that HP-SLNs have better brain targeting efficiency as compared to other formulations.

Stealth Amphotericin B nanoparticles for oral drug delivery: In vitro optimization

PurposeAmphotericin B (AmB) is an effective anti-fungal and anti-leishmanial agent. However, AmB has low oral bioavailability (0.3%) and adverse effects (e.g., nephrotoxicity). The objectives of this study were to improve the oral bioavailability by entrapping AmB in pegylated (PEG) poly lactide co glycolide copolymer (PLGA–PEG) nanoparticles (NPs). The feasibility of different surfactants and stabilizers on the mean particle size (MPS) and entrapment efficiency were also investigated. Materials and methodsNPs of AmB were prepared by a modified emulsification diffusion method employing a vitamin E derivative as a stabilizer. Physicochemical properties and particle size characterization were evaluated using Fourier Transform Infra-Red spectroscopy (FTIR), differential scanning calorimetry, scanning electron microscopy and transmission electron microscopy. Moreover, in vitro dissolution profiles were performed for all formulated AmB NPs. ResultsMPS of the prepared spherical particles of AmB ranged from 26.4±2.9 to 1068±489.8nm. An increased stirring rate favored AmB NPs with a smaller MPS. There was a significant reduction in MPS, drug content and drug release, when AmB NPs were prepared using the diblock polymer PLGA–PEG with 15% PEG. Addition of three emulsifying agents poly vinyl pyrrolidone (PVP), Vitamin E (TPGS) and pluronic F-68 to AmB formulations led to a significant reduction in particle size and increase in drug entrapment efficiency (DEE) compared to addition of PVP alone. FTIR spectroscopy demonstrated a successful loading of AmB to pegylated PLGA–PEG copolymers. PLGA–PEG copolymer entrapment efficiency of AmB was increased up to 56.7%, with 92.7% drug yield. After a slow initial release, between 20% and 54% of AmB was released in vitro within 24h phosphate buffer containing 2% sodium deoxycholate and were best fit Korsmeyer–Peppas model. In conclusion, PLGA–PEG diblock copolymer with 15% PEG produced a significant reduction (>70%) in MPS with highest drug content. The percentage of PEG in the copolymer and the surfactant/stabilizer used had a direct effect on AmB release in vitro, entrapment efficiency and MPS. These developed formulations are feasible, effective and improved alternatives to other carriers for oral delivery of AmB.

Preparation of polyamide nanocapsules of Aloe vera L. delivery with in vivo studies.

Aloe vera is the oldest medicinal plant ever known and the most applied medicinal plant worldwide. The purpose of this study was to prepare polyamide nanocapsules containing A. vera L. by an emulsion diffusion technique with in vivo studies. Diethyletriamine (DETA) was used as the encapsulating polymer with acetone ethyl acetate and dimethyl sulfoxide (DMSO) as the organic solvents and Tween and gelatin in water as the stabilizers. Sebacoyl chloride (SC) monomer, A. vera L. extract, and olive oil were mixed with the acetone and then water containing DETA monomer was added to the solution using a magnetic stirrer. Finally, the acetone was removed under vacuum, and nanocapsules were obtained using a freeze drier. This study showed that the size of the nanocapsule depends on a variety of factors such as the ratio of polymer to oil, the concentration of polymers, and the plant extract. The first sample is without surfactant and the size of nanocapsules in the sample is 115 nm. By adding surfactant, nanocapsules size was reduced to 96 nm. Nanocapsules containing A. vera were administered to rats and the effects were compared with a normal control group. The results showed that in the A. vera group, the effect is higher. The nanocapsules were identified by scanning electron microscopy (SEM), zeta potential sizer (ZPS), and Fourier-transform infrared spectroscopy (FT-IR).

Formulation and in vitro evaluation of mucoadhesive microspheres of pioglitazone hydrochloride

The work was aim to formulate and evaluate mucoadhesive microspheres of Pioglitazone Hydrochloride for treatment of diabetes type-2 by combining the pote ntial advantages of mucoadhesion with controlled dr ug delivery using various ratio of polymers. Mucoadhesive microspheres were prepared by emulsion diffusion solvent evaporation technique. Microspheres were found to be discrete, spherical and free flowing. They range d in particle size from 73-125 µm , drug release shown was 73.39-91% and mucoadhesiveness was 68-84%. Mainly in this Stirring speed affects particle size, Concentration of HPMC K100 affects drug release and concentration of Carbopol 934 affects mucoadhesiveness The microspheres exhibits good mucoadhesive property in in-vitr o wash off test and showed high drug entrapment efficiency. Pioglitazone Hydrochloride release from these mic rospheres was slowed, extended and depended on the type of polymer used. The work has demonstrated that among all the formulations of microspheres, particularly those of formulation F8 are promising candidates for the su stained release of Pioglitazone Hydrochloride .

Targeting liver cancer via ASGP receptor using 5-FU-loaded surface-modified PLGA nanoparticles

Context: Liver cancer is widespread liver malignancy in the world, for an estimated one million deaths annually. Objective: In present work, lactobionic acid conjugated PLGA nanoparticles (LDNPs) bearing 5-Fluorouracil (5-FU) were developed for targeted delivery to hepatocellular carcinoma. Materials and methods: Lactobionic acid conjugated PLGA was used to prepare LDNPs using modified emulsion diffusion method. Results: They were characterised for particle morphology, particle size (below 150 nm), zeta potential and polydispersity index (PDI ∼0.35), entrapment efficiency (∼60.23%), and cumulative percent drug release. Discussion: LDNPs in ex-vivo cell line studies on human cancer cell line HepG2 exhibited significantly higher cytotoxicity compared to 5-FU and DNPs (unconjugated PLGA NPs) with growth inhibition 50% (GI50) of 66.7 µg/mL, 50.2 µg/mL and 35.5 µg/mL, respectively. In vivo studies exhibited higher drug concentration about 37.52 ± 0.68% in liver as compared to other organs and plasma. Conclusion: Thus, LDNPs showed high drug loading, specificity, biocompatibility and efficacy in treatment of liver cancer.

Preparation of polyamide nanocapsules of Elaeagnus angustifolia L. delivery with in vivo studies

The purpose of this study is to prepare polyamide nanocapsules containing Elaeagnus angustifolia L. using an emulsion diffusion technique with in vivo studies. Diethylenetriamine (DETA) was used as the encapsulating polymer in acetone ethyl acetate (EA) and dimethyl sulfoxide (DMSO) as the organic solvents, Tween 80, Tween 60, Tween 20, Gelatin, and sodium lauryl sulfate (SLS), in water as the stabilizers. Two ratios of organic to aqueous phases were used with each solvent and stabilizer. The nanocapsule E. angustifolia were obtained with a mean diameter of 60–180nm, zeta potential of −11.3mV, Particles Dispersion Index (PDI) of 0.2, and a high encapsulation efficiency of 0.98%. Acetone was superior to EA and DMSO, and Tween 20 was superior to Tween 80, Tween 60, Gelatin and SLS in obtaining smaller nanocapsules. An organic of aqueous phase ratio of 1:5 was shown to be more suitable for the smaller nanocapsules. Finally, nanocapsules containing E. angustifolia and calcium carbonate as well as calcium tablets available on the market, were administered to rats for 3 weeks, and the calcium levels were measured in their blood as well as compared to a normal control group. The results showed that the E. angustifolia group has a higher level of calcium in their blood.

Development of Piroxicam loaded SLN-based Hydrogel for Transdermal Delivery

The aim of present study was to construct and investigate the efficacy of solid lipid nanoparticles (SLNs) based hydrogel for transdermal delivery of non-steroidal anti-inflammatory drug (NSAID) piroxicam. Solid lipid nanoparticles (SLNs) of piroxicam were produced by solvent emulsification diffusion method in a solvent saturated system. The SLNs were composed of tripalmitin lipid, polyvinyl alcohol (PVA) as stabilizer, and solvent ethyl acetate. All the formulations were subjected to particle size analysis, zeta potential, drug entrapment efficiency, percent drug loading determination and in-vitro release studies. The SLNs formed were in nano-size range with maximum entrapment efficiency of 88.50±0.92. Further, Carbopol-934 was used as a gel matrix for preparation of hydrogel for improving the penetration rate across the skin and viscosity of piroxicam loaded SLNs for transdermal drug administration. The drug release behaviors from piroxicam loaded SLNs based hydrogel exhibited long duration and constant rate of drug release over 24 hr. Skin penetration of piroxicam loaded SLNs based hydrogel was assessed by confocal laser scanning microscopy (CLSM).

Formulation and Evaluation of Mefloquine Hydrochloride Nanoparticles

The present study deals with the formulation and evaluation of mefloquine hydrochloride nanoparticles. Mefloquine is a blood schizonticidal quinoline compound, which is indicated for the treatment of mild-to-moderate acute malarial infections caused by mefloquine-susceptible multi-resistant strains of P. falciparum and P. vivax. The purpose of the present work is to minimize the dosing frequency, taste masking toxicity and to improve the therapeutic efficacy by formulating mefloquine HCl nanoparticles. Mefloquine nanoparticles were formulated by emulsion diffusion method using polymer poly(ε-caprolactone) with six different formulations. Nanoparticles were characterized by determining its particle size, polydispersity index, drug entrapment efficiency, drug content, particle morphological character and drug release. The particle size ranged between 100 nm to 240 nm. Drug entrapment efficacy was &gt;95%. The in-vitro release of nanoparticles were carried out which exhibited a sustained release of mefloquine HCl from nanoparticles up to 24 hrs. The results showed that nanoparticles can be a promising drug delivery system for sustained release of mefloquine HCl.

Development and characterization of nanoparticles for the delivery of gemcitabine hydrochloride.

Gemcitabine (2,2-difluorodeoxycytidine) is a deoxycytidine analog, currently being used as a first-choice drug in pancreatic metastatic cancer. Gemcitabine is administered weekly as 30-minute infusion with starting dose ranging from 800 to 1250 mg/m2. The aim of the present work was to develop starch nanoparticles (NPs) for the delivery of gemcitabine hydrochloride that could reduce its dose related side effects and may prolong its retention time (24 hrs) for the treatment of pancreatic cancer. Nanoparticles were prepared by emulsification diffusion method with slight modifications. Size and morphology of nanoparticles were investigated. Particles were spherical in shape with slightly rough surfaces. Particle size and polydispersity index were 231.4 nm and 1.0, respectively while zeta potential of blank NPs and drug loaded NPs were found to be −11.8 mV and −9.55 mV, respectively. Percent entrapment efficiency of different formulations was around ∼54% to 65%. In vitro release profile studies showed that around 70%–83% of drug was released from different formulations. Anticancerous cell line studies were also performed in human pancreatic cell lines (MIA-PA-CA-2).

The effect of nano-coatings with α-tocopherol and xanthan gum on shelf-life and browning index of fresh-cut “Red Delicious” apples

The objective of this study was to prepare nanoparticles and nanocapsules using the emulsification–diffusion method, and then evaluate the effectiveness of several systems made with dl-α-tocopherol on the browning index and firmness in fresh-cut apples. Poly-ε-caprolactone was used as a biopolymer to form the membrane of nanocapsules and the matrix of nanospheres. To provide greater functionality to the coating, xanthan gum was added to some of the systems tested. Changes in the treated fruit were monitored during 18 days of cold storage. The micrographs obtained give evidence of the presence of capsular entities. Particle size was 174 to 240 nm, and the zeta potential was − 44 to − 56 mV, which indicates that the systems were stable. With respect to the browning index, nanocapsules proved to be the most effective system, followed by nanospheres. Firmness changes were reduced by applying nanocapsules and nanospheres, both of which limited variations in firmness to below 15% (6.1 and 6.3 N, respectively). These results confirm that the use of nanoparticle systems does indeed help maintain the quality of fresh-cut apples. This study shows the advantages of using edible coatings containing nanosystems to preserve fresh cut fruits in particular the apple. The results show clearly that nanotechnological coatings decrease the browning index and preserve the firmness by longer times compared with the xanthan gum and control. Nanocapsules containing dl-α-tocopherol were the best system followed by nanoemulsions and nanospheres. The systems were prepared by the emulsion–diffusion method from acceptable food materials. This process is efficient, versatile and of simple implementation to industrial level. On the other hand, the nanosystems can be easily applied by dipping or spraying as conventional coatings in production lines, and they do not require special equipment. Apparently the effect of nanosystems is attributed to their high superficial area and the modification of membrane permeability due to their lipophilic nature. Furthermore, the food industry is continuously growing, so that the application of antioxidants in a nanocapsule form is a choice of easy application, in accordance with current systems of conservation of fresh-cut fruit, helping to increase the shelf life of apples and other products of high marked demand, thereby reducing product losses.

Glyceryl monostearate based nanoparticles of mefenamic acid: Fabrication and in vitro characterization

ObjectiveThe aim of present research work was to fabricate and evaluate the Mefenamic acid (MF) loaded Solid lipid nanoparticles (SLNs) using Glyceryl monostearate as lipid and tween 80 as surfactant. MethodMF loaded SLNs were prepared by Solvent Emulsification diffusion technique. Various batches were prepared by hit and trial method varying drug to lipid ratio and surfactant concentration and evaluated for particle size & distribution, particle morphology, zeta potential, percent drug loading and percent drug entrapment efficiency. ResultAmong various lipids like Glyceryl monostearate, Stearic acid and Palmitic acid, GMS was selected for the fabrication of SLNs it was due to the highest solubility of MF in GMS as compared to other above mentioned lipids. Particle size, polydispersity index (PDI), zeta potential, percent drug loading and percent drug entrapment efficiency were found to be 109.7 nm, 0.34, −20.3 mV, 43.00 and 75.45 respectively. Morphologically the SLNs were found to be spherical with rough surfaces. The optimized formulation exhibited 93.28% cumulative drug release after 24 h, while the release mechanism was found to be Fickian diffusion type. ConclusionIt is concluded that Solvent Emulsification diffusion technique is suitable for fabrication of MF loaded SLNs. All evaluating parameters of optimized SLNs were found to be in acceptable range.