Search

Chronic wounds, such as burns and diabetic ulcers, are complex wounds sustained by the skin that require life-long rehabilitation and have the potential to deteriorate and get infected. The number of patients with this ailment has been steadily increasing. This illness demands the use of new dressings with the best capabilities for managing wound healing. This study created an gel with carboxymethylcellulose (CMC), hyaluronic acid (HA), and zinc oxide nanoparticles (ZnO NPs). According to the findings, the manufacturing technique with a 1:4 ratio of HA and CMC gel had the best viscosity. Additionally, varying concentrations of zinc oxide nanoparticles (ZnO NPs) were added to the formula. Variations included 0.05, 0.125, 0.5, 1.0, 3.0, 5.0, and 10% by weight. In order to find the ideal dose and formulation, physical properties, an anti-bacterial test, and a cell migration assay were carried out. The samples with concentration of 0.5, 1.0, 3.0, 5.0 and 10% w/v showed ability to kill gram-positive and gram-negative bacteria. Wound healing experiments showed that cells proliferated for HA/CMC/ZnO gel with a weight-to-volume ratio of 0.05% and 1.0% w/v. In conclusion, according to all (physical and biological) characterization, the HA/CMC/ZnO gel with a weight-to-volume ratio of 1.0% w/v was found to have a considerable standard for wound-healing materials, demonstrating a promising effect against bacteria. [ABSTRACT FROM AUTHOR]

Andrographolide is a group of diterpenoid lactone isolated from Andrographis paniculata (Burm. F.) NEES. One of the analogues is 19-O-triphenylmethylandrographolide (RSPP050) which possesses anticancer activity. In seeking to capitalise on the last property, we have investigated the in vitro tumour targeting capabilities and MRI imaging for hepatocellular carcinoma. In this study, we have designed galactose-targeted and non-targeted micelles comprised of poly(ethylene glycol)-b-poly(lactide) that enveloped RSPP050 as an anticancer agent and superparamagnetic iron oxide (SPIO) as a contrast agent. The targeting abilities were endeavored by examining the cellular uptake with MTT assay, fluorescence microscopy, Prussian blue staining, and in vitro MRI. Targeted SPIO micelles as a T2* contrast agent decreased the relative T2* MRI intensity at 3 h. Results revealed that galactose micelles displayed 10.91 ± 0.19% drug loading content, −37.17 ± 0.63 mV zeta potential, and these micelles at the concentration of 0.5 µg/ml exhibited higher cytotoxicity than non-targeted micelles and free RSPP050 after incubation for 24 h. Fluorescence microscopy and Prussian blue staining at 3 h demonstrated significant cellular uptake by HepG2 cells. Thus, anticancer activity of RSPP050 could be improved using galactose as a targeting ligand and theranostic function was achieved using SPIO. [ABSTRACT FROM AUTHOR]

Two types of nanospheres, namely clindamycin-loaded nanospheres (CN) and rifampicin-loaded nanospheres (RN) were successfully prepared using emulsion solvent evaporation technique. Poly(ε-caprolactone-random-d,l-lactide)-block-poly(ethylene glycol)-block-poly(ε-caprolactone-random-d,l-lactide) (PLEC) was used for preparing nanospheres. CN and RN were coated on an antibiotic-impregnated silicone tube surface by spray coating technique. The formulations of antibiotic-loaded nanospheres (CN and RN) and the amount of spray coating cycles were optimized. Drug-loading content (DLC), encapsulation efficiency, zeta potential, and size of nanospheres were characterized. The optimal ratios of PLEC to clindamycin; and PLEC to rifampicin were both at 2:1. Drug-loading contents of CN and RN were 2.62 ± 0.04% and 7.02 ± 0.02%, respectively. The optimum coating of 90 cycles was provided DLCs of 0.0637 ± 0.033 wt.% and 0.0613 ± 0.018 wt.% for rifampicin and clindamycin, respectively. The coating of silicone tube was able to prolong the release of both antibiotics for at least 30 days. Antibacterial activity test was performed using MRSA (ATCC 43300) and S. Epidermidis (ATCC 12228). Moreover, the cytotoxicity of antibiotic-loaded nanospheres coated on silicone tubes was evaluated. The coated silicone tube showed antibacterial activity for at least 28 days and was biocompatible with L929 cells. [ABSTRACT FROM AUTHOR]

Two types of chlorhexidine-loaded nanoparticles (CHX-loaded nanoparticles) were prepared: poly(ethylene glycol)-block-poly(ε-caprolactone) micelles and poly(ε-caprolactone) nanospheres. They were prepared by the solvent evaporation method and were used to coat the Foley urinary catheters. The 90 bilayers of dip coating with chlorhexidine-micelles and the 40 cycles of spray coating with chlorhexidine-nanospheres were investigated. The coating provided the CHX content as high as 93.59 ± 9.14 μg/cm2 and the thickness of coating was 9.17 ± 0.08 μm. Coated catheters were also investigated in the in vitro chlorhexidine-release, antibacterial activity, and cytotoxicity. CHX release from the coated catheters was controlled. The bacteria proliferation was inhibited up to 28 days and showed the reduction of bacteria on the coated catheter surface. Coated catheters showed no biofilm on the surface. In addition, the cytotoxicity showed no cytotoxic effect from the coating. These nanocoating systems promoted potential uses for indwelling catheter and urinary tract infection. [ABSTRACT FROM AUTHOR]

The present study examined the cytotoxicity and magnetic resonance imaging (MRI) distribution of cancer-targeted, MRI-visible polymeric micelles that encapsulate doxorubicin (DOX) and superparamagnetic iron oxide (SPIO) and are conjugated with glucose as a targeting ligand. In this study, the micelles were investigated the clinical potential of glucose-micelles, in vitro cytotoxicity assays of nonencapsulating or SPIO-and-DOX-coencapsulating micelles were performed on L929 mouse fibroblasts, and we found that glucose-micelles did not exert in vitro cytotoxic effects. Next, in vitro MRI detectability of glucose SPIO micelles was evaluated at the loaded SPIO content of 2.5% and 50%, and it was found that glucose-micelles can increase MRI relaxivity (r2*) at high SPIO loading. Furthermore, 50% SPIO micelles persisted in the blood circulation for up to 5 days (slow liver clearance) as determined by in vivo MRI. For in vivo toxicity evaluation, 50% SPIO/DOX micelles at a dose up to 18 (mg DOX)/(kg body weight) showed no impact on animal health according to clinical chemistry and clinical hematology laboratory testing. Altogether, these results indicate that glucose-micelles can serve as an effective and safe drug delivery system. [ABSTRACT FROM AUTHOR]

In this study, chlorhexidine-loaded poly(ε-caprolactone) nanospheres (CHX-NS) were prepared and successfully coated on the urinary catheters. Properties of CHX-NS were evaluated including drug loading content and the nanosphere size. Effects of different lyoprotectants for long-term storage of CHX-NS were also investigated. In vitro release study and antibacterial activity were also conducted using 20 cycles coated-urinary catheters. Results showed that the high-pressure emulsification-solvent evaporation technique provided the drug loading content at 1.14 ± 0.16% and the size of nanospheres was 152 ± 37 nm. The suitable lyoprotectant for long-term storage of CHX-NS was sucrose which provided noticeably no aggregation at the degree of reconstitution at 89.95%. The amount of CHX loading on coated catheters was at 4.55 ± 0.31 mg. Drug release from the coated catheters in artificial urine could be prolonged up to 2 weeks and bacteria proliferation was inhibited up to 14 days. These results suggest that the antimicrobial activity of CHX-NS reduces the adherence of the uropathogens to the catheter surface. Chlorhexidine-loaded polymeric nanospheres were fabricated which can be successfully coated on urinary catheters. These systems have potential use for prolonged antimicrobial applications. [ABSTRACT FROM AUTHOR]

In this work, paclitaxel-encapsulated polymeric depots were prepared and characterized as drug delivery system for cancer chemotherapy against hepatocellular carcinoma. Effects of different parameters, including drug-loading content, polymer concentration and depot weight on depot formation, percentage of sustained-release taxol and drug release profile were evaluated. Paclitaxel-loaded depots were successfully formed at the polymer concentration above 25% w/v. For all formulations, paclitaxel could be encapsulated with very high percentage of sustained-release taxol (>90%). The release rate of paclitaxel from depots could be controlled by the amount of drug-loading content, polymer concentration and depot weight. Cytotoxicity against liver cancer cell line, HepG2, was evaluated by medium extraction method. Paclitaxel releasing from depots showed cytotoxic effect against HepG2 at different incubation times, whereas blank depots exhibited no cytotoxicity. [ABSTRACT FROM AUTHOR]

Background: Semi-synthetic andrographolide analogue (19-triphenylmethyl ether andrographolide, AG 050) is a C-19 substituted andrographolide which is the major constituent fromAndrographis PaniculataNees (Acanthaceae). The analogue has previously been reported to be highly cytotoxic against several cancer cell lines. Nevertheless, its poor water solubility limits clinical applications of this compound. Objectives: To improve the aqueous solubility and bioavailability of AG 050 by protonation and encapsulation in poly(ethylene glycol)-b-poly(d,l-lactide) (PEG-b-PLA) polymeric micelles. Materials and methods: PEG-b-PLA micelle was employed as a nanocarrier for AG 050. The physicochemical properties andin vitrocytotoxicity against cholangiocarcinoma (CCA) (KKU-M213) cell line were done in this study. Result and discussion: Hydrochloride salt of AG 050 (AG 050-P) greatly enhanced the solubility of this compound (15-fold). PEG-b-PLA was able to encapsulate AG 050-P in hydrophobic core with a significant increase in the amount of AG 050-P in aqueous solution (280-fold). Film sonication method provided greater results in drug-loading study as compared to micelles via solvent evaporation. In addition, the encapsulated AG 050-P exhibited sustained release pattern and excellent cytotoxicity activity against KKU-M213 with IC50of 3.33 µM. Conclusion: Nanoencapsulation of AG 050-P implicated its potential development for clinical use in CCA treatment. [ABSTRACT FROM AUTHOR]

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 againstStaphylococcus aureus(S. aureus) andCandida albicans(C. albicans), the main cause of hospital-acquired infections. Chlorophene-loaded nanospheres were effective againstS. aureus(>46 µg/mL) andC. 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. [ABSTRACT FROM AUTHOR]

Polymeric micelles have been successfully used to deliver a variety of therapeutic agents. Nonetheless, several limitations and considerations must be clarified and well-studied to achieve the highest therapeutic effect. In this study, a series of methoxy poly(ethylene glycol)-block-poly(ℇ-caprolactone) (PEG-b-PCL) and methoxy poly(ethylene glycol)-block-poly( D, L-lactide) (PEG-b-PLA) with varying molecular weight (MW) of hydrophobic core segment were synthesized. These block copolymers can form micelle with PCL or PLA as core-forming blocks and PEG as a coronal material. The effect of MW on micelle size and critical micelle concentration (CMC) was studied. DOX (DOX) was encapsulated inside the micelle core. Drug-loading content and size of micelles were studied. Drug release studies inside cells were evaluated by confocal laser scanning microscopy. In summary, the PLA core which is less hydrophobic than PCL showed higher CMC, smaller micelle size and faster DOX release inside nucleus. [ABSTRACT FROM AUTHOR]