In our study, the potential of bilosomes as novel vesicular carrier for the cutaneous delivery of the sulfone compound, Dapsone, for topical treatment of acne was investigated. The effect of different formulation variables (type and concentration of bile salt, and molar ratio of Span 60:cholesterol) on the properties of DPS- loaded bilosomes was investigated using a full factorial design. Design Expert software was used for data analysis and optimization of DPS- loaded bilosomes. The optimized bilosomes, chosen on the basis of their superior properties giving maximum entrapment, in-vitro release after different time intervals and RE% with minimum vesicle size. Results showed that the bilosome system prepared using Span® 60: Cholesterol (5:1) and containing 0.25 M sodium deoxycholate as the bile salt was found to obey these criteria, with a desirability value of 0.637. Therefore this system was chosen for further assessment for its morphological properties, zeta potential, thermal analysis using differential scanning calorimetry and X-ray diffractometry. Results revealed that the chosen bilosomes were spherical in shape with no aggregation, and contained DPS in a molecularly dispersed amorphous form. Finally, the capability of the optimized DPS-loaded bilosomes to deliver DPS through rat skin layers will be investigated and compared with that of DPS alcoholic solution. Results showed that the amounts of DPS retained in the skin treated with DPS-loaded bilosomes, and DPS alcoholic solution after 24h were found to be 170.57 ± 55.12, and 120.24 ± 10.7 µg/mL, respectively, representing about 1.5 fold higher drug retained in the bilosomes treated skin. Finally the safety and tolerability of the prepared bilosomes were assessed using histopathological examination, and revealed that the control untreated skin sections and skin sections treated with DPS-loaded bilosomes showed normal histological structures characterized by absence of defects or inflammation. Such results can be considered a good addition in the field of pharmaceutical drug delivery for effective topical therapy of acne.

Unmodified magnetic nanoparticles (MNPs) lack antibacterial potential. We investigated MNPs surface modifications that can impart antibacterial activity. Six MNPs species were prepared and characterized. Their antibacterial and antibiofilm potentials, surface affinity, and cytotoxicity were evaluated. Prepared MNPs were functionalized with citric acid, amine group, amino-propyl trimethoxy silane (APTMS), arginine, or oleic acid (OA) to give hydrophilic and hydrophobic MNPs with surface charge ranging from −30 to +30 mV. Prepared MNPs were spherical in shape with an average size of 6–15 nm. Hydrophobic (OA-MNPs) and positively charged MNPs (APTMS-MNPs) had significant concentration dependent antibacterial effect. OA-MNPs showed higher inhibitory potential againstS. aureusandE. coli(80%) than APTMS-MNPs (70%). Both particles exhibited surface affinity toS. aureusandE. coli.Different concentrations of OA-MNPs decreasedS. aureusandE. colibiofilm formation by 50–90%, while APTMS-MNPs reduced it by 30–90%, respectively. Up to 90% of preformed biofilms ofS. aureusandE. coliwere destroyed by OA-MNPs and APTMS-MNPs. In conclusion, surface positivity and hydrophobicity enhance antibacterial and antibiofilm properties of MNPs.

In this study, water-soluble chitosan lactate (CL) was reacted with lactobionic acid (LA), a disaccharide with remarkable affinity to hepatic asialoglycoprotein (ASGP) receptors, to form dual liver-targeting LA-modified-CL polymer for site-specific drug delivery to the liver. The synthesized polymer was used to encapsulate baicalin (BA), a promising bioactive flavonoid with pH-dependent solubility, into ultrahigh drug-loaded nanoparticles (NPs) via the ionic gelation method. The successful chemical conjugation of LA with CL was tested and the formulated drug-loaded LA-modified-CL-NPs were assessed in terms of particle size (PS), encapsulation efficiency (EE) and zeta potential (ZP) using full factorial design. The in vivo biodistribution and pharmacokinetics of the designed NPs were assessed using ^99mTc-radiolabeled BA following oral administration to mice and results were compared to ^99mTc-BA-loaded-LA-free-NPs and ^99mTc-BA solution as controls. Results showed that the chemical modification of CL with LA was successfully achieved and the method of preparation of the optimized NPs was very efficient in encapsulating BA into nearly spherical particles with an extremely high EE exceeding 90%. The optimized BA-loaded-LA-modified-CL-NPs showed an average PS of 490 nm, EE of 93.7% and ZP of 48.1 mV. Oral administration of ^99mTc-BA-loaded-LA-modified-CL-NPs showed a remarkable increase in BA delivery to the liver over ^99mTc-BA-loaded-LA-free-CL-NPs and ^99mTc-BA oral solution. The mean area under the curve (AUC_0–24) estimates from liver data were determined to be 11-fold and 26-fold higher from ^99mTc-BA-loaded-LA-modified-CL-NPs relative to ^99mTc-BA-loaded-LA-free-CL-NPs and ^99mTc-BA solution respectively. In conclusion, the outcome of this study highlights the great potential of using LA-modified-CL-NPs for the ultrahigh encapsulation of therapeutic molecules with pH-dependent/poor water-solubility and for targeting the liver.