Self-Gelling Solid Lipid Nanoparticle Hydrogel Containing Simvastatin as Suitable Wound Dressing: An Investigative Study

Hydrogels, an advanced interactive system, is finding use as wound dressings, however, they exhibit restricted mechanical properties, macroscopic nature, and may not manage high exudate wounds or incorporate lipophilic actives. In this study, we developed a self-gelling solid lipid nanoparticle (SLNs) dressing to incorporate simvastatin (SIM), a lipophilic, potential wound-healing agent, clinically limited due to poor solubility (0.03 mg/mL) and absorption. The study explores unconventional and novel application of SIM. The idea was to incorporate a significant amount of SIM in a soluble form and release it slowly over a prolonged time. Further, a suitable polymeric surfactant was selected that assigned a self-gelling property to SLNs (SLN-hydrogel) so as to be used as a novel wound dressing. SLNs assign porosity, elasticity, and occlusivity to the dressing to keep the wound area moist. It will also provide better tolerance and sensory properties to the hydrogel. SIM loaded SLN-hydrogel was prepared employing an industry amenable high-pressure homogenization technique. The unique hydrogel dressing was characterized for particle size, zeta potential, Fourier transform infra-red spectroscopy, powder X-ray diffraction, differential scanning calorimetry, rheology, and texture. Significant loading of SIM (10% w/w) was achieved in spherical nanoparticule hydrogel (0.3 nm (nanoparticles) to2 µm (gelled-matrix)) that exhibited good spreadability and mechanical properties and slow release up to 72 h. SLN-hydrogel was safe as per the organization for economic co-operation and development (OECD-404) guidelines, with no signs of irritation. Complete healing of excision wound observed in rats within 11 days was 10 times better than marketed povidone-iodine product. The presented work is novel both in terms of classifying a per se SLN-hydrogel and employing SIM. Further, it was established to be a safe, effective, and industry amenable invention.

Comparison of the Release rate, Penetration and Physical stability of p-Methoxycinamic acid (PMCA) in Nanostructured Lipid Carriers (NLC), Solid Lipid Nanoparticle (SLN) and Nanoemulsion (NE) systems

Objective: The p-methoxycinnamic acid (PMCA) was known has antiinflamatory effect which is difficult to dissolve in water, to increase the penetration to the skin it’s was loaded in the nanostructured lipid carrier (NLC) delivery system used the combination of beeswax-cacao oleum and virgin coconut oil (VCO), compared with solid lipid nanoparticle (SLN) and nanoemulsion (NE) delivery systems. Material and Method: PMCA concentrations of 1% in each system were prepared by the high shear homogenization method, namely NLC-PMCA and SLN-PMCA; and was prepared by emulsification method namely NE-PMCA. Then all systems are characterized and tested for release rate, penetration into the rat skin, also were tested for physical stability. The results of this research: All systems have a pH value in the range of 4.2 - 4.5 which falls into the skin's pH range (4-6.5). The viscosity of the NLC-PMCA, SLN-PMCA and NE-PMCA systems are 30.03±6.29; 93.77± 6.11 and 3.43±0.16 cPs, respectively. The particle size of NLC-PMCA, SLN-PMCA and NE-PMCA are 423.6± 33.6; 830.7±71.3 and 57.1±1.6nm, respectively. The release rate of PMCA in the NLC-PMCA, SLN-PMCA and NE-PMCA system are 0.2210±0.0089; 0.1972±0.0145 and 0.4690±0.0228µg/cm2/minute, respectively. The depth of PMCA penetration in the NLC-PMCA, SLN-PMCA and NE-PMCA system at 30 minutes after application are 1173.0±37.8; 703.3±117.2; 1414.3±106.4µm, respectively and at 2 hours after application are 1268.8±111.9; 945.6±140.4; 1832.5±92.8μm, respectively. The NLC-PMCA has no physical changes in 14 days’ storage, whereas the SLN-PMCA consistency becomes thicker and the NE-PMCA becomes turbid. Conclusion: NLC-PMCA has better release rate and deeper penetration than SLN-PMCA, even though it is lower and shallower than NE-PMCA, but NLC-PMCA has better physical stability than SLN-PMCA and NE-PMCA.

Preparation and Characterization of Solid Lipid Nanoparticles of Cinnacalcet HCl

Objective: The objective of the present research is to formulate solid lipid nanoparticles of cinnacalcet HCl to improve its oral bioavailability. Methods: Cinnacalcet hydrochloride exhibits poor oral bioavailability of 20 to 25 % because of low aqueous solubility and first pass metabolism. The formulations were optimised using Box-Behnken Design. Solid lipid nanoparticles formulation was prepared using hot homogenization and ultra sonication method. Results and Discussion: Precirol ATO 05, Soya lecithin and poloxamer 407 were selected as lipid, surfactant and co-surfactant respectively. For optimistaion the desirable goal was fixed for various responses entrapment efficiency, particle size and (time taken for diffusion of 85% drug) T85%. The optimized single dose of solid lipid nanoparticle obtained using box behnken design consisting of 30 mg of cinnacalcet HCl, 200 mg of precirol ATO 05, 250 mg of soya lecithin and 0.2% w/v of poloxamer. 407. The pharmacokinetic study revealed that optimized formulation was found to increase the oral bioavailability nearly 3 times compared to aqueous suspension of pure drug. Conclusion: Thus optimized solid lipid nanoparticle explicated the potential of lipid-based nanoparticles as a potential carrier in improving the oral delivery.