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Background: Chelidonine is a potent anticancer against several cell lines. However, low bioavailability and water solubility restrict the clinical applications of this compound. Objective: The aim of this research was to develop a novel formulation of chelidonine encapsulated in the nanoparticles of poly(d l-lactic-co-glycolic acid) (PLGA) employing vitamin E D-α-tocopherol acid polyethylene glycol 1000 succinate (E TPGS) as a modifier to increase bioavailability. Methods: Chelidonine-encapsulated PLGA nanoparticles were fabricated using a single emulsion method and modified by various concentrations of E TPGS. Nanoparticles were recognized in terms of morphology, surface charge, drug release, size, drug loading, and encapsulation efficiency to obtain the optimized formulation. The cytotoxicity of different nanoformulations in HT-29 cells was evaluated using the MTT assay. The cells were stained with propidium iodide and annexin V solution to evaluate apoptosis using flow cytometry. Results: Spherical nanoparticles prepared with 2% (w/v) of E TPGS had the optimum formulation in the nanometer size range (153± 12.3 nm), with a surface charge of -14.06 ± 2.21 mV, encapsulation efficiency of 95.58 ± 3.47 %, drug loading of 33.13 ± 0.19%, and drug release profile of 73.54 ± 2.33. In comparison with non-modified nanoparticles and free chelidonine, E TPGS-modified nanoformulations improved anti-cancer capability even after three-months storage. Conclusion: Our results showed that E TPGS is an effective biomaterial for surface modification of nanoparticles, which can serve as a potential treatment for cancer.

Discharge of organic dyes from different industries into receiving rivers and natural streams poses serious problems for the environment because of their toxicity. These dyes are not readily biodegradable and therefore, their removal from effluents is urgent. Various methods used for removal of dyes from wastewater, such as coagulation, flocculation, filtration or reverse osmosis are quite expensive and have a low removal efficiency. On the contrary, Advanced oxidation processes (AOPs) using metal oxide semiconductors like ZnO, are capable to operate effectively and efficiently to degrade many dye pollutants.In this work, ZnO nanoparticles were successfully synthesized via a simple solvothermal method with different solvents. Scanning electron microscopy (SEM) imaging showed that nanoflower, nanorod, and nanosphere ZnO particles were produced when water, 1-hexanol, and ethylene glycol were used as the solvent, respectively. Nanoflower ZnO particles exhibited higher photocatalytic reduction efficiencies under UV light irradiation than nanosphere and nanorod particles. Results suggested a close relationship between the photocatalytic activity and the particle morphology and size which was due to using different solvents in preparation processes. Also, the recovery of ZnO nanoparticles was investigated and samples showed stable photodegradation efficiencies after being reused for three times.

The cellulose-based textiles currently used in hospitals are good conducive materials for cross-infection or transmission of diseases caused by microorganisms. Thus, great interest has been recently found in the antibacterial finishing of fabrics for practical applications to prevent the infection incidence. In this work, we developed novel SnO2/ZnO/chitosan bionanocomposites by one-step simultaneous sonochemical/sol–gel deposition to prepare an antibacterial textile as a model for combating bacterial infections. The different prepared samples were characterized using transmission electron microscope, X-ray diffraction, and scanning electron microscopy (SEM) indicating the embedded SnO2 and ZnO nanoparticles in treated fabrics. The treated fabrics were used to evaluate antibacterial activities against Escherichia coli and Streptococcus aureus as a model for Gram-negative and Gram-positive bacteria, respectively, using disk diffusion method in dark conditions as an in vitro model for treatment of bacterial wound infection. The procedure was more developed in terms of SnO2/ZnO molar ratio and using chitosan and citric acid to improve the antibacterial properties of the fabrics and their wash durability, respectively. The highest antibacterial activity of the fabrics was attained in a 50 min sonochemical coating process using SnO2/ZnO 1:2 molar ratio in initial sol and simultaneously deposited chitosan and citric acid. The presence of chitosan as complexing agent, citric acid as crosslink agent, and SnO2–ZnO heterojunction as important influencing parameters synergistically enhanced both the antimicrobial efficiency and maintenance of modified cotton durability after performing several washing cycles.

Protection against bacterial contamination remains a demand for healthcare textiles such as wound dressings to reduce or eliminate hospital-acquired infections related to antibiotic-resistant bacteria. We report herein a simple and straightforward in situ approach to deposit copper oxide and titanium oxide nanoparticles onto cotton fabric using a sonochemical-mediated sol–gel method. Modification of the cotton surface was achieved by incorporation of citric acid (CA) and polyethylene glycol (PEG) to improve the attachment of the nanoparticles and reduce the attachment of bacteria to the cotton surface, respectively. The resultant cotton fabric was used against Escherichia coli as a Gram-negative bacterium and Staphylococcus aureus as a Gram-positive bacterium in dark condition as an in vitro model for treatment of bacterial wound infection. The effects of different treatment parameters including duration and frequency of ultrasonic irradiation, surface modification with PEG and/or CA, and cotton chemical composition with different metal oxide molar ratios on the antibacterial activity of the treated cotton fabric were studied. All treated cotton fabrics showed antibacterial activity, with higher efficiency for those coated with CuO or CuO/TiO2 (1:1 molar ratio) among the single metal oxide and composite-modified cotton fibers, respectively. Our results show that such functionalized cotton fibers could actively fight the spread of bacterial infections by preventing bacterial adhesion, enabling more efficient bonding, and ultrasonically promoting generation of nanoparticles and their strong adhesion to the fabric surface.

Burn injuries are one of the major global health problems. Despite aggressive local and systemic treatment to minimize infection, severe burn wounds continue to become infected with environmental and nosocomial pathogens at relatively high rates. We developed an ultrasound assisted sol–gel technique to prepare treated cotton fibers by coating fabric surface with NiO/organic polymer/enzyme matrix for in vitro evaluation of antibacterial activity. The surface modification was performed to bond more efficiently NiO nanoparticles using cellulase enzyme, to reduce initial bacterial attachment on the hydrophilic surface using poly(ethylene glycol), and to promote ultrasonic generation and to overcome agglomeration of the nanoparticles, respectively. Disk diffusion method was used to quantify the efficacy of NiO-based cottons against Pseudomonas aeruginosa and Staphylococcus aureus as two most burn wound pathogens isolated from burn wound swabs and tissue biopsies of hospitalized burn patients. Almost ba...

Sol–gel dip coating method has been employed for the deposition of nanostructured single nickel oxide (NiO) and zinc oxide (ZnO) films and multilayered NiO/ZnO/NiO and ZnO/NiO/ZnO films. The structural, morphology and optical properties of prepared films were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV–vis spectroscopy, respectively. XRD analysis showed that ZnO-based films crystallized in write phase and presented an epitaxial orientation depending on the substrate. SEM images also showed uniform size distribution around 30–70 nm for all samples. Antibacterial effectiveness of NiO and ZnO- based films were tested against general Escherichia coli (E. coli ATCC 25922) and Streptococcus aureus (S. aureus, ATCC 29213) as Gram negative and Gram positive model, respectively, using the so-called drop-test method under UV light illumination and dark conditions. ZnO/NiO/ZnO film was found to be the most toxic among tested samples, followed by ZnO, NiO/ZnO/NiO and NiO films. Samples exposure to UV light resulted in higher activity compared to dark conditions against both E. coli and S. aureus, but considerably more effective in the former case. The obtained results were discussed according to the lattice matching between the heteroepitaxial films and structural modification as key roles on the preferential growth orientation and antibacterial activity.

Background In recent years, bioactive bioceramics such as bioglass and hydroxyapatite (HA) have been introduced as a remarkable development in the field of medicine due to their bio-adaptability, non-toxicity, and persistence, in vivo. They have many potential applications in the repair of bone defects and hence they have attracted significant interest from scholars. Objectives The aim of this study was to synthesize inorganic matrix CuO-based bioglasses and evaluate their antibacterial activity against aerobic bacterial infections in bone implants. Methods Nano-composite samples of silica-based bioactive glass, 60S BG with nano-powder CuO, were synthesized using the sol-gel method and then assessed with regard to their antibacterial properties against Staphylococcus aureus using well diffusion agar. The samples included BG58S (58%SiO2, 36%CaO, 6%P2O5), BG/10CuO (58%SiO2, 26%CaO, 6%P2O5, 10%CuO), and BG/20CuO (48%SiO2, 26%CaO, 6%P2O5, 20%CuO). To evaluate their bioactivity, the prepared samples of BG/20CuO, BG/10CuO, and BG58S were immersed in simulated body fluids (SBF). The surface morphology and structure of the samples before and after immersion in the SBF were characterized using scanning electron microscopy (SEM) and Fourier transform infrared (FTIR), respectively. Then, the BG/20CuO and BG/10CuO samples were loaded in clindamycin, an antibiotic widely used in the treatment of osteomyelitis, and their release profiles were studied in phosphate buffer solution. Results It was observed that the growth inhibition zone increased through clindamycin release due to the increasing CuO percentage in the nanocomposite of bioactive glass. The bioactivity of the nanocomposite/bioglass with CuO was superior to that of bioglass alone. In this study, the BG/20CuO sample showed a sustained release of clindamycin, which is sufficient for a drug delivery system. Conclusions Increasing the Cu nanoparticles in bioactive glass samples leads to the release of Cu2+, which has a positive effect on the antibacterial mechanism, as well as decreasing the cultured Staphylococcus colonies found on the bioglasses. Therefore, it seems that the nanocomposite/bioglass of CuO is a promising option for aerobic bacterial inhibitor systems in common bone implant infections.