A pre formulation study of tetracaine loaded in optimized nanostructured lipid carriers

Tetracaine TTC is a local anesthetic broadly used for topical and spinal blockade, despite its systemic toxicity. Encapsulation in nanostructured lipid carriers NLC may prolong TTC delivery at the site of injection, reducing such toxicity. This work reports the development of NLC loading 4 TTC. Structural properties and encapsulation efficiency EE amp; 8201; gt; amp; 8201;63 guided the selection of three pre formulations of different lipid composition, through a 23 factorial design of experiments DOE . DLS and TEM analyses revealed average sizes 193 220 nm , polydispersity lt; amp; 8201;0.2 , zeta potential amp; 8722; amp; 8201;21.8 to amp; 8722; amp; 8201;30.1 mV and spherical shape of the nanoparticles, while FTIR ATR, NTA, DSC, XRD and SANS provided details on their structure and physicochemical stability over time. Interestingly, one optimized pre formulation CP TRANS TTC showed phase separation after 4 months, as predicted by Raman imaging that detected lack of miscibility between its solid cetyl palmitate and liquid Transcutol lipids. SANS analyses identified lamellar arrangements inside such nanoparticles, the thickness of the lamellae been decreased by TTC. As a result of this combined approach DOE and biophysical techniques two optimized pre formulations were rationally selected, both with great potential as drug delivery systems, extending the release of the anesthetic gt; amp; 8201;48 h and reducing TTC cytotoxicity against Balb c 3T3 cell

Bioactive glass containing 90% SiO2 in hard tissue engineering : an in vitro and in vivo characterization study.

Bioactive glass has been proved to have many applications in bioengineering due to its bone regenerative properties. In this work, an innovative, highly resorbable bioactive glass containing 90% SiO2 (BG90) to be used as a bone substitute was developed. The BG90 was synthetized by the sol?gel process with the dry step at room temperature. The biomaterial showed in vitro and in vivo bioactivities even with silica content up to 90%. Moreover, the BG90 presented high porosity and surface area due to its homogenously interconnected porous network. In vitro, it was observed to have high cell viability and marked osteoblastic differentiation of rat bone marrow?derived cells when in contact with BG90 ion extracts. The BG90 transplantation into rat tibia defects was analysed at 1, 2, 3, 4, 7, and 10 weeks post?operatively and compared with the defects of negative (no graft) and positive (autogenous bone graft) controls. After 4 weeks of grafting, the BG90 was totally resorbed and induced higher bone formation than did the positive control. Bone morphogenetic protein 2 (BMP?2) expression at the grafting site peaked at 1 week and decreased similarly after 7 weeks for all groups. Only the BG90 group was still exhibiting BMP?2 expression in the last experimental time. Our data demonstrated that the BG90 could be an attractive candidate to provide useful approaches in hard?tissue bioengineering