Skin delivery aspects of benzoyl peroxide-loaded solid lipid nanoparticles for acne treatment.

BACKGROUND: Benzoyl peroxide (BPO) has been a mainstay of topical acne treatment for years. However, is frequently accompanied by cutaneous irritation and erythema. To reduce these side effects many novel drug delivery systems have been developed in the past, of which solid lipid nanoparticles (SLN) demonstrate clear dominance. Hence, we developed a facile method to prepare stable SLN of BPO and evaluated their anti-bacterial activity. RESULTS: BPO-SLN optimized using 2(3) full factorial design provided high occlusion factor, low permeation rate, increased drug deposition, reduced skin irritation and strong anti-bacterial activity in contrast with marketed product. CONCLUSION: Desired goals were achieved by factorial design approach in shortest possible time with minimum number of experiments. The developed BPO-SLN system provided controlled drug release, thereby reducing the well-known side effects.

Structure function attributes of gold nanoparticle vaccine association: effect of particle size and association temperature.

Many biotherapeutic applications of gold nanoparticles make use of conjugated or adsorbed protein moieties. Physical parameters of association such as particle size, morphology, surface chemistry and temperature influences the protein-nanoparticle association and thereby their interaction with the biological environment. In present study, effect of size of chitosan reduced gold nanoparticles (CsAuNPs) and association temperature on structure and function of tetanus toxoid (TT) vaccine has been investigated. CsAuNPs were synthesized in the sizes of 20±3, 40±5 and 80±7 nm followed by loading of TT. Binding process of CsAuNPs with TT was investigated at their predetermined micro molar concentrations. Upon binding of TT onto CsAuNPs, particle surface was characterized using X-ray photoelectron spectroscopy. CD spectroscopic evaluation of TT bound 20 nm CsAuNPs led to 75% reduction in secondary structure of TT and thereby compromised immune function. Binding of TT with 40 and 80 nm sized CsAuNPs did not cause significant modifications in secondary structure or function of TT. Thermodynamic studies using temperature dependent fluorescence spectroscopy revealed an increase in association constants with the temperature. Based on thermodynamic data three phases in CsAuNPs and TT association process were traced. Samples from these distinct phases were also investigated for immunological recognition. Ex-vivo interaction of TT-CsAuNPs with TT positive and negative sera followed by relative change in particle size and zeta potential was studied. The findings here suggests prominent role of particle size and association temperature on adsorbed TT structure and function. Such studies may help in engineering functional nanotherapeutics.