ABSTRACT
BACKGROUND: Leishmaniasis is the most important parasitic disease in Iran and is the third highest rate of rural cutaneous leishmaniasis in the world. Chitosan-polyethylene oxide nanocomposite fibers can be a suitable replacement for ordinary bandages. For the first time, in the absence of any published reports, the present in vitro study aimed to evaluate the anti-leishmanial effects of chitosan (CS)-polyethylene oxide (PEO)-berberine nanofibers on Leishmania major. METHODS: The present experimental study was conducted in 2018 in Tehran, Iran. The CS-PEO nanofibers containing berberine, as a natural anti-parasitic agent, were prepared using the electrospinning technique. Biocompatibility and fibroblast proliferation on nanofibers were investigated. In addition, the anti-leishmanial activity of CS-PEO nanofibers in both the promastigote and amastigote stages of Leishmania major was evaluated after parasite vital staining and MTT assay and compared to a control group. Statistical analysis was performed using SPSS software (version 18.0). Statistically significant differences were determined using the one-way ANOVA. The Duncan and Dunnett post hoc tests were used for within-group comparisons. P<0.05 was considered statistically significant. RESULTS: The results showed that nanofiber scaffolds with a mean diameter of 77.5±19.5 nm were perfect, regular, bead-free, and non-toxic, on which fibroblast cells grew well and proliferated. In addition, the optical density indicated that berberine 20% (w/v) significantly prevented promastigotes growth (IC50=0.24 µg/mL) and amastigotes death (IC50=0.91 µg/mL) compared with other concentrations and the control group. CONCLUSION: The study on the cytotoxic effects showed that CS-PEO-berberine nanofibers had strong lethal effects on Leishmania major in promastigote and amastigote stages in vitro. Further studies are required to investigate the effects of this nanofiber on leishmanial ulcers in laboratory animals and clinical cases.
ABSTRACT
OBJECTIVES: Rapid healing of cutaneous leishmaniasis as one of the most important parasitic diseases leads to the decrease of scars and prevention of a great threat to the looks of the affected people. Today, the use of nano-scaffolds is rapidly increasing in tissue engineering and regenerative medicine with structures similar to the target tissue. Chitosan (CS) is a bioactive polymer with antimicrobial and accelerating features of healing wounds, which is commonly used in biomedicine. This study aimed to investigate the effects of CS/polyethylene oxide (PEO)/berberine (BBR) nanofibers on the experimental ulcers of Leishmania major in BALB/c mice. MATERIALS AND METHODS: CS/PEO/BBR nanofibers were prepared by the electrospinning method, and their morphology was examined by SEM, TEM, and AFM. Then, water absorption, stability, biocompatibility, porosity, and drug release from nano-scaffolds were explored. Afterward, 28 BALB/c mice infected with the parasite were randomly divided into control and experimental groups, and their wounds were dressed with the produced nano-scaffolds. Finally, the effect of nanobandage on the animals was investigated by macroscopic, histopathologic, and in vivo imaging examinations. RESULTS: The prepared nanofibers were completely uniform, cylindrical, bead-free, and biocompatible with an average diameter of 94±12 nm and had appropriate drug release. In addition, the reduced skin ulcer diameter (P=0.000), parasite burden (P=0.003), changes in the epidermis (P=0.023), and dermis (P=0.032) indicated significantly strong effectiveness of the produced nano-scaffolds against leishmania ulcers. CONCLUSION: Studies showed that CS/PEO/BBR nanofibers have a positive effect on the rapid healing of leishmania ulcers. Future studies should focus on other chronic ulcers treatment.
ABSTRACT
An ionic liquid-mediated multi-walled carbon nanotube (MWCNT)-polydimethylsiloxane (PDMS) sorbent was developed for headspace solid-phase microextraction (HS-SPME) of phenolic compounds from human urine samples. Sol-gel method was used to prepare this sorbent. For this purpose, MWCNTs were functionalized covalently and were attached chemically to the hydroxyl-terminated PDMS. Prepared fiber showed high thermal stability (over than 320°C) and good lifespan (>210 times). These good performances can be attributed to the performance of carbon nanotubes and sol-gel method. Affecting parameters on the efficiency of HS-SPME were investigated and optimized. Under the optimal conditions, linear dynamic ranges were observed over a range of 0.002-200 ng mL-1 with limits of detection from 0.0005 to 0.005 ng mL-1 and limits of quantitation between 0.002 and 0.02 ng mL-1 The relative standard deviations for one fiber (repeatability) (n = 5) at three different concentrations (0.05, 2 and 100 ng mL-1) were obtained from 4.6 up to 6.7% and between fibers or batch to batch (n = 3) (reproducibility) in the range of 5.7-7.8%. Urine samples were used as real samples. All real samples were spiked at 0.5 ng mL-1 of understudy analytes and the relative recovery percentages obtained from 90.7 to 102.1%.
