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Objective: To prepare a PEOz modified single-walled carbon nanotube delivery system (PEOz-SWCNT) with the anti- tumor drug paclitaxel (PTX) as a model drug (PTX@PEOz-SWCNT) and evaluate its physical and chemical properties, in vitro drug release, biocompatibility, and in vitro antitumor effects. Methods: PEOz-SWCNT was synthesized by chemical coupling method, and the products were characterized by UV-Vis spectroscopy (UV-Vis) and infrared spectroscopy (FTIR). The particle size and Zeta potential of PEOz-SWCNT were measured. The drug-loaded complex PTX@PEOz-SWCNT was prepared and the loading efficiency and encapsulation efficiency were measured. The dialysis method was used for in vitro drug release. The safety of the application of PEOz-SWCNT was evaluated by in vitro hemolysis test. The MTT method was used to evaluate the biocompatibility of the material and the growth inhibition rate of the drug-loaded complex on MCF-7 cells. The uptake of Coumarin-6 (C6)-labeled vector in MCF-7 cells was examined by fluorescence inversion microscope. Results: The average particle size of PEOz-SWCNT was (219.8 ± 2.9) nm and the Zeta potential was (-35.23 ± 0.74) mV. The loading efficiency of PTX@PEOz-SWCNT was (38.19 ± 0.74) %, and the encapsulation efficiency was (94.38 ± 0.94)%. The drug release rate was significantly accelerated at pH 5.0, showing obvious pH responsiveness. There was no obvious hemolysis when the concentration of PEOz-SWCNT was below 0.4 mg/mL. The biocompatibility of PEOz-SWCNT on Hela cells was good, and the PTX@PEOz-SWCNT could significantly enhance the cell growth inhibition rate on MCF-7 cells. The in vitro antitumor activity test results showed that the cell uptake of the C6@PEOz-SWCNT was increased compared to C6@SWCNT. Conclusion: PTX@PEOz-SWCNT drug delivery system is promising in tumor-targeted drug delivery.
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Objective To explore the power output and blood compatibility of a novel electromagnetic pulsatile blood pump. Methods First, a theoretical model was established to analyze the driving force of the blood pump, and the experimental driving voltage satisfying the conditions was calculated based on this model. Then, the output flow rate, output pressure characteristics and hemolysis performance of the new blood pump in vitro were preliminarily analyzed by simulated circulation experiments. Results The experimental result showed that when the pump load was 73-5 mmHg (9-78 kPa, 1 mmHg=0-133 kPa), the driving voltage was 35 V and the pulsation frequency was 75 beats/min, the flow rate of the pump was 3-18 L/min, producing high, low and average pressure of 132, 66, 98 mmHg (17-56, 8-78, 13-03 kPa), and the normalized index of haematolysis (NIH) in vitro was (0-049 15+0-003 75) mg/dL. Conclusions The new pulsatile blood pump can satisfy the clinical requirements for perfusion of isolated organs and short-term assistance of cardiopulmonary bypass, which is of great significance to the development of cardiopulmonary bypass blood pump.
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Objective To study the prescription and preparation technology of tea tree oil gel, and evaluate its anti-inflammatory efficacy, antibacterial effect and the irritation. Methods The tea tree oil gel was prepared using the carbomer-940 as gel matrix, Cremophor RH-40 and 1,2-propylene glycol as solvents. The appearance characters, pH value, viscosity, moisture retention, drug content, and the stability were observed. The anti-inflammatory efficacy, the antibacterial effect and the irritation of tea tree oil gel were evaluated. Results The prescription of tea tree oil gel was selected as following tea tree oil (1.0%), Cremophor RH-40 (5.0%), 1,2-propylene glycol (5.0%), Carbomer-940 (0.6%), glycerol (8.0%), with distilled water 100 g, adjusting pH to 5.0 by triethanolamine. The gel exhibited transparent, well uniformity, appropriate viscosity and fine coating expansion performance, with pH value of 5.52 ± 0.03, viscosity at (48 782 ± 25) mPa•s, the moisture retaining rate of (93.32 ± 0.38)% for 24 h test, containing tea tree oil of (9.55 ± 0.10) mg/g. The inhibition rate of tea tree oil gel on the mouse auricle swelling was 46.15%, which was significantly different as compared to the negative control group (P < 0.01). The diameters of inhibition zone of the gel against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa respectively was (15.50 ± 0.96), (15.25 ± 2.36), and (15.75 ± 1.91) mm. The half hemolysis rate (LC50) and the hemoglobin degeneration index (DI) respectively were 456 157 mg/L and 157.98%. The tea tree oil gel had no eye irritation in rabbits based on the value of LC50/DI 2 887.44. Fourteen consecutive’days administration indicated that the tea tree oil gel had no skin irritation in rabbits. The illumination score of irritative reaction to the rabbit skin was 0.125 after a single administration, while that was 0.036 after successive administration experiment. The results of high speed centrifugalization cold- resistance and heat-resistance tests showed that the preparation exhibited good stability, which needed to be kept tightly in a cool place and protected from light. Conclusion The formulation design was reasonable, while the preparation technology was simple, corresponding to the main index of the gel for topical application, with good anti-inflammatory efficacy, antibacterial effect and safety, which offered the basis for further research and development of tea tree oil.
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requirement of medical materials for hemolysis experiment (<5%) .MTT assay showed that , after 4 days of culture , the optical densi-ties were 0.498 ±0.218 and 0.566 ±0.266 in the 120℃12 h and 24 h groups and 0.668 ±0.268 and 0.769 ±0.213 in the 150℃12 h and 24 h groups, while after 8 days, the optical densities were 0.767 ±0.267 and 0.836 ±0.236 in the 120℃12 h and 24 h groups and 0.765 ±0.265 and 0.903 ±0.303 in the 150℃12 h and 24 h groups, all significantly higher than in the non-CaTiO3 group at 4 (0.341 ±0.143) and 8 days (0.731 ±0.121) (P<0.05). Conclusion The CaTiO3 coating on titanium is neither mutagenic nor hemolytic and has no toxicity on osteoblasts .Instead, it can promote the proliferation of osteoblasts , and therefore is a valuable coating material for implants .
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Objective To evaluate the biocompatibility of acellular bladder matrix patch as the pelvic floor repair alternative ma-terial .Methods The combination of in vivo and in vitro biological experiments including cytotoxicity ,haemolysis and vaginal im-plant tests were employed to evaluate the biocompatibility of this material .Results In the cytotoxicity test ,the material toxicity was the grade 0-1 .The hemolysis rate of the material extract liquid was 1 .5% .The general and histological observation showed that the material did not cause the host immunologic rejection and led to slight foreign body reaction after implanting ,which was ba-sically degraded in 12 weeks after transplantation .Conclusion Acellular bladder matrix exhibits better biocompatibility ,but needs to adjust its degradation rate in order to adapt to the requirements of pelvic floor repair operation .