The aim of this work was to increase the efficacy of erythromycin ethyl succinate by encapsulation in beeswax lipid matrix using Myrj 52 as emulsifier. Different batches of SLM＇s （solid-lipid microparticles） were f...The aim of this work was to increase the efficacy of erythromycin ethyl succinate by encapsulation in beeswax lipid matrix using Myrj 52 as emulsifier. Different batches of SLM＇s （solid-lipid microparticles） were formulated and stable ones were selected. The encapsulation efficiency and loading capacities were calculated. The batch with the highest loading capacity was used for further assays. The particle size was determined by light microscopy. The sensitivity of different clinical bacterial isolates to erythromycin was tested using in vitro cultures and E. coli was selected for efficacy tests. The activity of the formulated drug was tested in the in vitro culture and compared to that of the unformulated drug. White albino mice were infected with E. coli and left for one day to develop significant bacteremia. They were then divided into 4 groups （n = 4） and treated with the formulation and unformulated drug at a dose of 7.14 mg/kg 8 hourly for 56 hours. A third group was given SLM＇s that do not contain drug, while another group was left untreated. The selected batch has an encapsulation efficiency of 94.83% with a loading capacity of 3.88%. The particle size was 17 ± 4 μm. At the end of the three day period of treatment, the group treated with unformulated erythromycin had much stooling anti weakness in the mice, and some deaths were recorded, while that treated with the formulation had 33.8% bacteremia and the clinical signs had largely subsided. The other two groups recorded deaths the following day after bacteremia induction. The results show marked improvement in efficacy of erythromycin ethyl succinate by formulation in SLMs with beeswax and lecithin as lipid matrix.展开更多
Background: This study focuses on the fabrication and optimization of Ti6Al4V alloy latticestructures produced by the Selective Laser Melting (SLM) process. Such structures areincreasingly used in biomedical implants ...Background: This study focuses on the fabrication and optimization of Ti6Al4V alloy latticestructures produced by the Selective Laser Melting (SLM) process. Such structures areincreasingly used in biomedical implants due to their potential to match the mechanicalproperties of human bone. Key features influencing their performance include porosity ratio,surface roughness, elastic modulus, and yield strength. Achieving a balance between theseparameters is essential for ensuring both mechanical integrity and biological compatibility.Methods: The Taguchi method integrated with Grey Relational Analysis (GRA) wasemployed to optimize the SLM process parameters—laser power (160-240 J), scanningspeed (1000-1500 mm/min), and hatch spacing (0.06-0.12 mm). The optimization aimed toproduce lattice structures with properties closely resembling human bone. Experimentaltrials were conducted to evaluate the effects of these parameters on porosity, surfaceroughness, elastic modulus, and yield strength, followed by statistical and relational analysisto determine the optimal configuration. Results: The results revealed that higher scanningspeed, wider hatch spacing, and lower laser power increased the porosity ratio compared toCAD models. A strong inverse relationship was observed between porosity and both yieldstrength and elastic modulus. Increasing laser power substantially reduced surfaceroughness. Through Taguchi-GRA optimization, the optimal parameter combination wasdetermined as laser power of 240 J, scanning speed of 1250 mm/min, and hatch spacing of0.06 mm. Under these conditions, the obtained values were: modulus of elasticity (0°) = 20GPa, modulus of elasticity (90°) = 18.874 GPa, yield strength (0°) = 265 MPa, yieldstrength (90°) = 260 MPa, porosity = 48.565%, and surface roughness = 6.223 μm.Conclusion: The optimized SLM parameters successfully produced Ti6Al4V latticestructures with mechanical and morphological characteristics compatible with human bone.The study highlights the critical balance between process parameters and structuralfeatures, providing a systematic approach for tailoring lattice structures for biomedicalapplications through Taguchi and GRA-based optimization.展开更多
文摘The aim of this work was to increase the efficacy of erythromycin ethyl succinate by encapsulation in beeswax lipid matrix using Myrj 52 as emulsifier. Different batches of SLM＇s （solid-lipid microparticles） were formulated and stable ones were selected. The encapsulation efficiency and loading capacities were calculated. The batch with the highest loading capacity was used for further assays. The particle size was determined by light microscopy. The sensitivity of different clinical bacterial isolates to erythromycin was tested using in vitro cultures and E. coli was selected for efficacy tests. The activity of the formulated drug was tested in the in vitro culture and compared to that of the unformulated drug. White albino mice were infected with E. coli and left for one day to develop significant bacteremia. They were then divided into 4 groups （n = 4） and treated with the formulation and unformulated drug at a dose of 7.14 mg/kg 8 hourly for 56 hours. A third group was given SLM＇s that do not contain drug, while another group was left untreated. The selected batch has an encapsulation efficiency of 94.83% with a loading capacity of 3.88%. The particle size was 17 ± 4 μm. At the end of the three day period of treatment, the group treated with unformulated erythromycin had much stooling anti weakness in the mice, and some deaths were recorded, while that treated with the formulation had 33.8% bacteremia and the clinical signs had largely subsided. The other two groups recorded deaths the following day after bacteremia induction. The results show marked improvement in efficacy of erythromycin ethyl succinate by formulation in SLMs with beeswax and lecithin as lipid matrix.
文摘Background: This study focuses on the fabrication and optimization of Ti6Al4V alloy latticestructures produced by the Selective Laser Melting (SLM) process. Such structures areincreasingly used in biomedical implants due to their potential to match the mechanicalproperties of human bone. Key features influencing their performance include porosity ratio,surface roughness, elastic modulus, and yield strength. Achieving a balance between theseparameters is essential for ensuring both mechanical integrity and biological compatibility.Methods: The Taguchi method integrated with Grey Relational Analysis (GRA) wasemployed to optimize the SLM process parameters—laser power (160-240 J), scanningspeed (1000-1500 mm/min), and hatch spacing (0.06-0.12 mm). The optimization aimed toproduce lattice structures with properties closely resembling human bone. Experimentaltrials were conducted to evaluate the effects of these parameters on porosity, surfaceroughness, elastic modulus, and yield strength, followed by statistical and relational analysisto determine the optimal configuration. Results: The results revealed that higher scanningspeed, wider hatch spacing, and lower laser power increased the porosity ratio compared toCAD models. A strong inverse relationship was observed between porosity and both yieldstrength and elastic modulus. Increasing laser power substantially reduced surfaceroughness. Through Taguchi-GRA optimization, the optimal parameter combination wasdetermined as laser power of 240 J, scanning speed of 1250 mm/min, and hatch spacing of0.06 mm. Under these conditions, the obtained values were: modulus of elasticity (0°) = 20GPa, modulus of elasticity (90°) = 18.874 GPa, yield strength (0°) = 265 MPa, yieldstrength (90°) = 260 MPa, porosity = 48.565%, and surface roughness = 6.223 μm.Conclusion: The optimized SLM parameters successfully produced Ti6Al4V latticestructures with mechanical and morphological characteristics compatible with human bone.The study highlights the critical balance between process parameters and structuralfeatures, providing a systematic approach for tailoring lattice structures for biomedicalapplications through Taguchi and GRA-based optimization.
