Chitosan films incorporated with nettle (Urtica Dioica L.) extract-loaded nanoliposomes: II. Antioxidant activity and release properties

Chitosan films were loaded with NE nettle (Urtica dioica L.) extract (NE) at concentrations of 0, 0.5, 1 and 1.5%w/w in the free or nanoliposomal form to obtain active and nanoactive films, respectively. The antioxidant potential of the films containing NE-loaded nanoliposomes was decreased in comparison of free NE incorporated films. Diffusion of NE to soybean oil was enough to delay the induction of the oxidation of soybean oil stored for 60 days in contact with chitosan based films. Release studies indicated that the release rate of NE in 95% ethanol simulant significantly decreased by the nanoencapsulation of NE. The diffusion coefficient (D) for chitosan films containing 1.5%w/w of free and encapsulated NE at 25?°C was 18.80 and 3.68?×?10^?7 cm² s^?1, respectively. Moreover, the formation of nanoliposomes diminished the increasing effect of temperature on the release rate as when storage temperature increased from 4?°C to 40?°C.     

In vitro and in vivo activities of ticarcillin-loaded nanoliposomes with different surface charges against Pseudomonas aeruginosa (ATCC 29248)

Background

Pseudomonas aeruginosa exhibits multiple antibiotic resistance mechanisms. Different studies have shown that entrapment of antibiotics into liposomes could increase their anti-Pseudomonas activity. The objectives of this study were to prepare ticarcillin loaded-nanoliposomes with variable surface charges and evaluate their in vitro and in vivo efficacies against Pseudomonas aeruginosa (ATCC 29248).

Methods

Ticarcillin-loaded nanoliposomes with positive, negative and neutral surface charges were prepared by extrusion method. Ticarcillin encapsulation efficacies for different formulations were measured by HPLC method. Minimum inhibitory concentration (MIC) of ticarcillin nanoliposomal forms against strain ATCC 29248 were determined by broth dilution method. The killing rate of Pseudomonas aeruginosa was exposed to various concentrations of ticarcillin in free and nanoliposomal forms were analyzed. Ultimately, in vivo therapeutic efficacy of nanoliposomes in burned mice skin infected with strain ATCC 29248 was investigated.

Results

The encapsulation efficacies for ticarcillin-loaded cationic nanoliposomes were significantly higher (76% ± 0.17) than those of neutral (55% ± 0.14) and anionic (43% ± 0.14) nanoliposomes. The MIC of free, cationic, neutral and anionic nanoliposomal forms of ticarcillin against ATCC 29248 were to 24, 3, 6 and 48 mg/L, respectively. The killing rates of ticarcillin-loaded cationic nanoliposomes were higher than those of free and other drug formulations. Treatment by ticarcillin-loaded nanoliposomes with positive, neutral and negative surface charges resulted in almost 100, 60 and 20% survival rates, respectively.

Conclusion

Our data suggested that cationic ticarcillin-loaded nanoliposomes because of high effectiveness would be a good choice to treatment of Pseudomonas aeruginosa infections.     

Binary Medical Nanofluids by Combination of Polymeric Eudragit Nanoparticles for Vehiculization of Tobramycin and Resveratrol: Antimicrobial,Hemotoxicity and Protein Corona Studies

The development of smart nanoparticles (NPs) became a trend to enhance the delivery of drugs. In the present work, Tobramycin (TB), an aminoglycoside antibiotic that displays several undesirable side effects, has been encapsulated into cationic Eudragit®E100 (E100) NPs for the treatment of infections caused by Pseudomonas aeruginosa. Combination with neutral Eudragit®NE30D (NE30D) NPs containing resveratrol (RSV), a strong natural antioxidant, increased the antimicrobial activity of TB (75% higher than free TB). NPs were stabilized with 1.0% (w/v) poloxamer 188 (P188) or poloxamer 407 (P407) as surfactants. E100 NPs showed 83.3 ± 8.5%, and 70.1 ± 2.7 encapsulation efficiency (EE) of TB with P188 and P407 coatings, respectively. The presence of NPs was confirmed by DLS and TEM studies. TB was controlled released from NPs for 6 h. Hemotoxicity tests of NPs in the range of MIC values on human blood gave negative results. Analysis of Surface Plasmon Resonance verified that NE30D/P407/RSV does not interact with plasma proteins BSA, IgG or fibrinogen, besides E100/P188/TB interact with BSA, findings that are compatible with a negligible in vivo clearance of the nanovehicles. The obtained results show a potential binary fluid composed of two NPs to highly improve the effectiveness of conventional antibiotics.     

Influence of chitosan coating on the liposomal surface on physicochemical properties and the release profile of nanocarrier systems

Chitosan-coated nanoliposomes containing etofenprox or alpha-cypermethrin prepared by ultrasonic homogenization maintained a size distribution in the nanometre range. Nanoliposomes were constructed using different types and concentrations of chitosan to regulate the mean size and surface charge. As the chitosan concentration (0.1-0.5%, w/v) and the degree of deacetylation increased, surface charge also increased. The encapsulation efficiency and release profile were measured by gas chromatography. Encapsulation efficiency decreased slightly as chitosan concentration increased (0.1-0.5%, w/v). As the intrinsic surface charge or concentration of the coating material increased, the release period of the entrapped core material was extended (chitosans A and B; 0.1 and 0.3%, w/v). The results indicate that diverse preparation conditions could affect the physicochemical properties and release profile of the resulting nanocarrier systems.     

A prebiotic matrix for encapsulation of probiotics: physicochemical and microbiological study

This work aims to develop an encapsulated oral-synbiotic supplement by studying the effect of adding inulin in alginate beads and observing its ability to protect three probiotic strains: Pediocucus acidilactici, Lactobacillus reuteri and Lactobacillus salivarius. Beads of different inulin concentrations 0%, 5%, 10%, 15% and 20% (w/v) in 2% (w/v) alginate solution were prepared by the extrusion/ionotropic gelation method. Polymer distribution within beads was characterised using confocal laser scanning microscopy. Interactions between alginate and inulin were monitored by Fourier transform infra-red spectroscopy (FTIR). Effect of encapsulation on viability, antimicrobial ability, acid tolerance and bile tolerance of probiotic strains were investigated. Antimicrobial and probiotic properties of bacterial strains were not affected by encapsulation. Bacterial protection against acidity was increased by adding inulin. Beads with 5% w/v inulin were the most effective in bacterial protection against bile-salts. To our knowledge, this work is the first to use such high concentrations of inulin.     

Superiority of liquid crystalline cubic nanocarriers as hormonal transdermal vehicle: comparative human skin permeation-supported evidence

ABSTRACT

Objectives: The aim of this investigation was to explore the feasibility of various nanocarriers to enhance progesterone penetration via the human abdominal skin.

Methods: Four progesterone-loaded nanocarriers; cubosomes, nanoliposomes, nanoemulsions and nanomicelles were formulated and characterized regarding particle size, zeta potential, % drug encapsulation and in vitro release. Structural elucidation of each nanoplatform was performed using transmission electron microscopy. Ex vivo skin permeation, deposition ability and histopathological examination were evaluated using Franz diffusion cells.

Results: Each nanocarrier was fabricated with a negative surface, nanometric size (≤ 270 nm), narrow size distribution and reasonable encapsulation efficiency. In vitro progesterone release showed a sustained release pattern for 24 h following a non-Fickian transport diffusion mechanism. All nanocarriers exhibited higher transdermal flux relative to free progesterone. Cubosomes revealed a higher skin penetration with transdermal steady flux of 48.57.10^–2 ± 0.7 µg/cm² h. Nanoliposomes offered a higher percentage of skin progesterone deposition compared to other nanocarriers. Based on the histopathological examination, cubosomes and nanoliposomes were found to be biocompatible for transdermal application. Confocal laser scanning microscopy confirmed the ability of fluoro-labeled cubosomes to penetrate through the whole skin layers.

Conclusion: The elaborated cubosomes proved to be a promising non-invasive nanocarrier for transdermal hormonal delivery.     

Influence of chitosan coating on the liposomal surface on physicochemical properties and the release profile of nanocarrier systems

Chitosan-coated nanoliposomes containing etofenprox or alpha-cypermethrin prepared by ultrasonic homogenization maintained a size distribution in the nanometre range. Nanoliposomes were constructed using different types and concentrations of chitosan to regulate the mean size and surface charge. As the chitosan concentration (0.1–0.5%, w/v) and the degree of deacetylation increased, surface charge also increased. The encapsulation efficiency and release profile were measured by gas chromatography. Encapsulation efficiency decreased slightly as chitosan concentration increased (0.1–0.5%, w/v). As the intrinsic surface charge or concentration of the coating material increased, the release period of the entrapped core material was extended (chitosans A and B; 0.1 and 0.3%, w/v). The results indicate that diverse preparation conditions could affect the physicochemical properties and release profile of the resulting nanocarrier systems.     

Herbal Extracts Encapsulated Nanoliposomes as Potential Glucose-lowering Agents: An in Vitro and in Vivo Approach Using Three Herbal Extracts

Encapsulation of polyphenol-rich herbal extracts into nanoliposomes is a promising strategy for the development of novel therapeutic agents against type 2 diabetes mellitus. An attempt was made to encapsulate aqueous, ethanol, and aqueous ethanol (70% v/v) extracts of Senna auriculata (L.) Roxb., Murraya koenigii (L.) Spreng,. and Coccinia grandis (L.) Voigt into nanoliposomes and to screen acute bioactivities in vitro and in vivo. A wide spectrum of bioactivity was observed of which aqueous extracts encapsulated nanoliposomes of all three plants showed high bioactivity in terms of in vivo glucose-lowering activity in high-fat diet-fed streptozotocin induced Wistar rats, compared to respective free extracts. The particle size, polydispersity index, and zeta potential of the aforementioned nanoliposomes ranged from 179–494 nm, 0.362–0.483, and (–22) to (–17) mV, respectively. The atomic force microscopy (AFM) imaging reflected that the nanoparticles have desired morphological characteristics and Fourier-transform infrared (FTIR) spectroscopy analysis revealed successful encapsulation of plant extracts into nanoparticles. However, only the S. auriculata aqueous extract encapsulated nanoliposome, despite the slow release (9% by 30 hours), showed significant (p < 0.05) in vitro α-glucosidase inhibitory activity and in vivo glucose-lowering activity compared to free extract, proving worthy for future investigations.     

Long-circulating nanoliposomes (LCNs) sustained delivery of baicalein (BAI) with desired oral bioavailability in vivo

Abstract

Long-circulating nanoliposomes (LCNs) containing Baicalein (BAI) were prepared by diethyl ether injection method in this paper. Using soybean phosphatidylcholine (SPC) and cholesterol (CHOL) as the carrier ingredients, BAI-loaded LCNs were formulated in optimized condition with encapsulation efficiency (EE) of 41.5?±?4.77%. The average diameter of BAI-loaded LCNs was ～709?nm determined by dynamic light scattering (PDI 0.43). Drug storage stability study showed that BAI-loaded LCNs were highly stable in phosphate-buffered saline (PBS, pH 7.4) at 4?°C. Additionally, the pharmacokinetic behaviors of BAI-loaded LCNs were studied using Kunming mice as experimental animals. Parallelly, free BAI solution was studied as control. As expected, it is found that LCNs-encapsulated BAI yields greater BAI oral bioavailability with 4.52 times of free BAI. These results suggest the potential applications of LCNs for the delivery of BAI.     

Preparation and optimization of chlorophene-loaded nanospheres as controlled release antimicrobial delivery systems

Chlorophene-loaded nanospheres with various formulation parameters were evaluated. The optimal formulation was found at 0.1% w/v of poloxamer 407, 15?mL of ethyl acetate and 20% initial chlorophene loading that provided the suitable size (179?nm), the highest loading content (19.2%), encapsulation efficiency (88.0%) and yield (91.6%). Moreover, encapsulation of chlorophene in nanospheres was able to prolong and sustain drug release over one month. Chlorophene-loaded nanospheres were effective against Staphylococcus aureus (S. aureus) and Candida albicans (C. albicans), the main cause of hospital-acquired infections. Chlorophene-loaded nanospheres were effective against S. aureus (>46?µg/mL) and C. albicans (>184?µg/mL). These nanospheres appeared to have profound effect on the time-dependent hemolytic activity due to gradual release of chlorophene. At the concentration of 46?µg/mL, nearly no HRBC hemolysis in 24?h compared to 80% of hemolysis from free drug. In conclusion, polymeric nanospheres were successfully fabricated to encapsulate chlorophene which can eliminate inherent toxicity of drugs and have potential uses in prolonged release of antimicrobial.     

Development and Characterization of Bioadhesive Vaginal Films of Sodium Polystyrene Sulfonate (PSS), a Novel Contraceptive Antimicrobial Agent

No HeadingPurpose. Polystyrene sulfonate (PSS) is a novel noncytotoxic antimicrobial contraceptive agent. A gel formulation of PSS was found safe for vaginal administration in phase I clinical trials. The purpose of the current study was to develop and evaluate novel bioadhesive vaginal film formulations of PSS.Methods. PSS films were prepared by solvent evaporation and optimized for various physical, mechanical, and aesthetic properties. Further, films were evaluated for various biological activities and safety.Results. Vaginal films containing 300 mg PSS per unit have been developed, using generally regarded as safe (GRAS) listed excipients. The films are colorless, transparent, thin, soft, and tough, dissolve rapidly in physiologic fluid to form a smooth, viscous and bioadhesive solution that could be retained in the vagina for prolonged intervals. Sperm function inhibition (hyaluronidase and cervical mucus penetration) and antimicrobial activities against human immunodeficiency virus (HIV) and herpes simplex virus (HSV) by PSS films were found comparable to PSS. Also, films did not inhibit normal vaginal microflora (Lactobacillus) and were noncytotoxic as indicated by negligible sperm immobilization and cytotoxicity to host cell assays.Conclusions. Rapidly dissolving bioadhesive vaginal film formulation of PSS with desired physical, mechanical, aesthetic, and biological properties is a suitable candidate vaginal microbicide for prevention of sexually transmitted disease (STDs) and is ready for toxicological and clinical evaluation.     

Ultrahigh verapamil-loaded controlled release polymeric beads using superamphiphobic substrate: D-optimal statistical design,in vitro and in vivo performance

Controlled-release multiparticulate systems of hydrophilic drugs usually suffer from poor encapsulation and rapid-release rate. In the present study, ultra-high loaded controlled release polymeric beads containing verapamil hydrochloride (VP) as hydrophilic model drug were efficiently prepared using superamphiphobic substrates aiming to improve patient compliance by reducing dosing frequency. Superamphiphobic substrates were fabricated using clean aluminum sheets etched with ammonia solution and were treated with 1.5% (w/v) perfluorodecyltriethoxysilane (PFDTS) alcoholic solution. The effect of the main polymer type (lactide/glycolide (PLGA) 5004A, PLGA 5010, and polycaprolactone (PCL)), copolymer (Eudragit RS100) content together with the effect of drug load on encapsulation efficiency (EE%) and in vitro drug release was statistically studied and optimized via D-optimal statistical design. In vivo pharmacokinetic study was carried out to compare the optimized system relative to the market product (Isoptin^®). Results revealed that superamphiphobic substrates were successfully prepared showing a rough micro-sized hierarchical structured surface upon observing with scanning electron microscope and were confirmed by high contact angles of 151.60?±?2.42 and 142.80°±05.23° for water and olive oil, respectively. The fabricated VP-loaded beads showed extremely high encapsulation efficiency exceeding 92.31% w/w. All the prepared systems exhibited a controlled release behavior with Q12?h ranging between 5.46 and 95.90%w/w. The optimized VP-loaded system composed of 150?mg (1.5% w/v) PCL without Eudragit RS100 together with 160?mg VP showed 2.7-folds mean residence time compared to the market product allowing once daily administration instead of three times per day.     

In vivo study of effects of artesunate nanoliposomes on human hepatocellular carcinoma xenografts in nude mice

Abstract

To investigate the effect of artesunate nanoliposomes on cultured cells in vitro and hepatocellular carcinoma xenografts in BALB/c-nu mice. Fluorescence polarization was applied for measurement of mitochondrial membrane fluidities; inhibition test of tumor cell proliferation in vitro was performed and nude mice xenograft model from human hepatocellular carcinoma (HCC) was established. Cytotoxicity of these compounds was evaluated by MTT assay on hepatocellular carcinoma xenografts in nude mice. Anisotropy (r-value) of blank nanoliposomes didn’t change, it had no statistically significance between the blank nanoliposomes group and the control group, it indicated that artesunate had no obvious effect on L-O2 human normal liver cells. IC₅₀ values of artesunate nanoliposomes and artesunate API (active pharmaceutical ingredient) against HepG-2 cells were 15.997 and 19.706?μg/ml; IC₅₀ values of the same drugs against L-O2 normal human liver cells were 100.23 and 105.54?μg/ml, respectively. Tumor growth inhibitory effect of artesunate nanoliposomes was 32.7%, and artesunate API was 20.5%, respectively. HepG-2 cells treated with artesunate nanoliposomes showed dose-dependent apoptosis. The antitumor effect of artesunate nanoliposomes on human hepatoma HepG2 cells were stronger than that of artesunate API at the same concentration.     

Nanoemulsion gel-based topical delivery of an antifungal drug: in vitro activity and in vivo evaluation

Abstract

Objective: In this study, attempt has been focused to prepare a nanoemulsion (NE) gel for topical delivery of amphotericin B (AmB) for enhanced as well as sustained skin permeation, in vitro antifungal activity and in vivo toxicity assessment.

Materials and methods: A series of NE were prepared using sefsol-218 oil, Tween 80 and Transcutol-P by slow spontaneous titration method. Carbopol gel (0.5%?w/w) was prepared containing 0.1%?w/w AmB. Furthermore, NE gel (AmB-NE gel) was characterized for size, charge, pH, rheological behavior, drug release profile, skin permeability, hemolytic studies and ex vivo rat skin interaction with rat skin using differential scanning calorimeter. The drug permeability and skin irritation ability were examined with confocal laser scanning microscopy and Draize test, respectively. The in vitro antifungal activity was investigated against three fungal strains using the well agar diffusion method. Histopathological assessment was performed in rats to investigate their toxicological potential.

Results and discussion: The AmB-NE gel (18.09?±?0.6?µg/cm²/h) and NE (15.74?±?0.4?µg/cm²/h) demonstrated the highest skin percutaneous permeation flux rate as compared to drug solution (4.59?±?0.01?µg/cm²/h) suggesting better alternative to painful and nephrotoxic intravenous administration. Hemolytic and histopathological results revealed safe delivery of the drug. Based on combined results, NE and AmB-NE gel could be considered as an efficient, stable and safe carrier for enhanced and sustained topical delivery for AmB in local skin fungal infection.

Conclusion: Topical delivery of AmB is suitable delivery system in NE gel carrier for skin fungal infection.     

Physicochemical Characterization of Hexetidine-Impregnated Endotracheal Tube Poly(vinyl Chloride) and Resistance to Adherence of Respiratory Bacterial Pathogens

Purpose. Ventilator-associated pneumonia is a frequent cause of mortality in intensive care patients. This study describes the physicochemical properties of hexetidine-impregnated poly(vinyl chloride) (PVC) endotracheal tube (ET) biomaterials and their resistance to microbial adherence (Staphylococcus aureus and Pseudomonas aeruginosa). Methods. PVC emulsion was cured in the presence of hexetidine (0-20% w/w) and was characterized in terms of drug release, surface properties (i.e., microrugosity/contact angle), mechanical (tensile) properties, and resistance to microbial adherence. Results. Under sink conditions, hexetidine release from PVC was diffusion-controlled. Increasing the concentration of hexetidine from 1% to 10% (w/w) (but not from 10% to 20% w/w) increased the subsequent rate of drug release. In general, increasing the concentration of hexetidine decreased both the tensile properties and hydrophobicity, yet increased PVC microrugosity. Following hexetidine release (21 days), the surface properties were similar to those of native PVC. The resistance of hexetidine-containing PVC (1% or 5%) to microbial adherence (following defined periods of drug release) was greater than that of native PVC and was constant over the examined period of hexetidine release. Conclusions. ET PVC containing 1% (w/w) hexetidine offered an appropriate balance between suitable physicochemical properties and resistance to microbial adherence. This may offer an approach with which to reduce the incidence of ventilator-associated pneumonia.     

胰岛素柔性纳米脂质体的口腔给药研究

目的探讨柔性纳米脂质体经口腔粘膜转运蛋白多肽类药物的可能性。方法用反相蒸发法制备胰岛素柔性纳米脂质体和普通脂质体,对其包封率、形态和粒径大小进行测定。以家兔为动物模型,口腔给药(bu)后,进行体内降糖实验,同时测定胰岛素水平变化。结果胰岛素柔性纳米脂质体与普通脂质体的包封率分别为(18.9±1.8)%和(22.1±2.2)%;粒径分别为(42±20) nm和(60±34) nm。透射电镜下,胰岛素柔性纳米脂质体的指纹状结构比普通脂质体更多,其他无明显区别。以sc胰岛素溶液(1 U·kg^-1)为对照,bu胰岛素柔性纳米脂质体组(10 U·kg^-1)的药理相对生物利用度为15.59%,相对生物利用度为19.78%,高于bu胰岛素溶液对照组(P<0.05)、胰岛素普通脂质体组(P<0.05)及空白柔性纳米脂质体与胰岛素混合物组(P<0.05)。结论胰岛素柔性纳米脂质体可能成为经口腔粘膜转运蛋白多肽类药物的有效载体。     

Liposomal Formulation of DIMIQ,Potential Antitumor Indolo[2,3-b]Quinoline Agent and Its Cytotoxicity on Hepatoma Morris 5123 Cells

The cytotoxic and antitumor activity of DIMIQ (5,11-dimethyl-5H-indolo[2,3-b]quinoline), synthetic analog of neocryptolepine, makes this compound a potential antitumor agent. An attempt to obtain liposomal form of DIMIQ·HCl was undertaken in the present study. Standard experimental conditions were chosen and information on the physicochemical parameters of the liposome dispersion containing studied indoloquinoline agent was collected. The effective and efficient encapsulation of DIMIQ·HCl (66.6%) in conventional liposomes (FAT-MLV, DMPC:DMPG 7:3 w/w at pH 7.0), uniformity of the size of liposomal vesicles, and high stability at pH 6.5 were demonstrated. Hemolysis of sheep erythrocytes induced by free form of DIMIQ·HCl was dramatically decreased after addition of liposome-entrapped DIMIQ·HCl. Treatment of hepatoma Morris 5123 cells for 24 hr with different concentrations of both free and its liposomal formulation of DIMIQ·HCl resulted in significant changes in cell morphology accompanied by reduction of cell viability.     

In vitro survival of Bifidobacterium bifidum microencapsulated in zein-coated alginate hydrogel microbeads

The Bifidobacterium bifidum susceptibility in gastrointestinal conditions and storage stability limit its use as potential probiotics. The current study was design to encapsulate B. bifidum using sodium alginate (SA, 1.4% w/v) and different concentration of zein as coating material, that is, Z₁ (1% w/v), Z₂ (3% w/v), Z₃ (5% w/v), Z₄ (7% w/v), Z₅ (9% w/v). The resultant microbeads were further investigated for encapsulation efficiency, survival in gastrointestinal conditions, release profile in intestinal fluid, storage stability and morphological characteristics. The highest encapsulation efficiency (94.56%) and viable count (>10⁷ log CFU/g) was observed in Z₄ (7% w/v). Viable cell count of B. bifidum was >10⁶ log CFU/g in all the zein-coated microbeads as compare to free cells (10³ log CFU/g) and SA (10⁵ log CFU/g) at 4 °C after 32 days of storage. Therefore, B. bifidum encapsulated in zein-coated alginate microbeads present improved survival during gastric transit and storage.     

Design and characterization of monolaurin loaded electrospun shellac nanofibers with antimicrobial activity

The aim of this study was to elucidate the optimized fabrication factors influencing the formation and properties of shellac (SHL) nanofibers loaded with an antimicrobial monolaurin (ML). The main and interaction effects of formulation and process parameters including SHL content (35%–40% w/w), ML content (1%–3% w/w), applied voltage (9–27 kV) and flow rate (0.4–1.2 ml/h) on the characteristic of nanofibers were investigated through a total of 19 experiments based on a full factorial design with three replicated center points. As a result, the SHL content was the major parameter affecting fiber diameter. Another response result revealed that the SHL content would be also the most significant negative impact on amount of beads. An increase in the concentration of SHL leaded to a reduction in the amount of beads. From the results of characterization study, it was proved that ML might be entrapped between the chains of SHL during the electrospinning process exhibiting an excellent encapsulation. According to the response surface area, small (~488 nm) and beadless (~0.48) fibers were obtained with the SHL and ML contents of 37.5% and 1.1% w/w respectively, at the applied voltage of 18 kV and the flow rate of 0.8 ml/h. In addition, the results of the kill-kinetic studies showed that SHL nanofibers loaded with ML exhibited an excellent antibacterial activity against Staphylococcus aureus, while Escherichia coli was less affected due to the hydrophilic structure of the its outer membrane. ML also exerted an antifungal activity by reducing the number of Candida albicans colonies. Based on their structural and antimicrobial properties, SHL nanofibers containing ML could be potentially used as a medicated dressing for wound treatment.     

Investigation of the role of alginate containing high guluronic acid on osteogenic differentiation capacity of human umbilical cord Wharton’s jelly mesenchymal stem cells

Background and aim: Cell encapsulation using biodegradable material has promising results for tissue engineering. Since pressure is an effective factor on stem cell behaviour and various concentrations of alginate create different pressures on the cells, therefore our goal was to evaluate the mechanical effect of 1/2% (w/v) and 1/8% (w/v) alginate containing high guluronic acid on viability and osteogenic capacity of HUCWJ cells.

Methods: Cell viability was evaluated by MTT assay after 1, 7 and 14 days. Alkaline phosphatase activity was evaluated by alkaline phosphatase assay kit after 14 and 21 days. Alizarin red S staining was performed for calcium deposition among histological section.

Results: MTT assay showed significant difference in the mean of viability rates between groups in day 14 (p 相似文献