Surface modified solid lipid microparticles based on homolipids and Softisan® 142: preliminary characterization

ObjectiveTo preliminarily investigate three different lipid matrices consisting of two natural homolipids from Capra hircus (goat fat) and Bovine Spp. (tallow fat) and one semi-synthetic lipid (Softisan® 142) separately structured with Phospholipon® 90G (P90G) as potential delivery systems for poorly water soluble drugs.MethodsThe structured lipid matrices were characterized by differential scanning calorimetry (DSC) and employed to prepare solid lipid microparticles (SLMs) by the melt homogenization method using gradient concentrations of polysorbate 80 and at different emulsification times of 2, 5 and 10 min using a Silverson mixer. The SLMs were analyzed for morphology and particle size, thermal properties, stability studies and determination of injectability.ResultsThe results showed that SLM production was optimum at 5 % of lipid matrices, 1.5 % of polysorbate 80 and emulsification time of 5 min. Increase in polysorbate 80 concentrations decreased the particle size of the SLMs. The SLMs were well formed, spherical, smooth and non-porous with particle sizes in the ranges of (13.90 ± 2.10) μm - (0.09 ± 0.01) μm for SLMs produced from the structured - tallow fat; (13.40 ± 1.30) μm - (0.10 ± 0.01) μm for the structured - goat fat and (13.40±2.00) μm - (2.10± 1.00)μm for the structured Softisan® 142 lipid matrices. DSC traces showed that Softisan® 142 was the most crystalline of all three bulk matrices due to its high enthalpy (?7.962 mW/mg) while tallow fat was the least (?5.067 mW/mg) but addition of P90G to the matrices lowered their enthalpies mostly in the structured goat fat matrices. The SLMs when stored at 4-6 ° were most stable and syringeable with 27 G needle.ConclusionsThis suggests that structured goat fat matrices with the enthalpy of ?2.813 mW/mg will mostly favour drug loading of some poorly soluble drugs more than tallow fat (?4.892 mW/mg) and Softisan® 142 (?5.501 mW/mg).     

Crohn’s disease:Evidence for involvement of unregulated transcytosis in disease etio-pathogenesis

Crohn’s disease(CD)is a chronic inflammatory bowel disease.Research has identified genetic predisposition and environmental factors as key elements in the development of the disease.However,the precise mechanism that initiates immune activation remains undefined.One pathway for luminal antigenic molecules to enter the sterile lamina propria and activate an immune response is via transcytosis.Transcytosis,although tightly regulated by the cell,has the potential for transepithelial transport of bacteria and h...     

LMW-400型MRI装置RF激励脉冲中尖刺噪声的消除

ＬＭＷ－４００型ＭＲＩ装置的射频激励信号中有尖刺噪声。此尖刺噪声在ＲＦ脉冲之后出现，具有约４０％的最大ＲＦ脉冲值。由于它存在于读出梯度期间。故必须消除此尖刺噪声以减少图像伪像。在调制板上进行的试验表明，由于两个控制信号的沿边突然升起，这种噪声是固有的。对此两种信号采用简单的积分电路，可成功地消除此种尖刺噪声。