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Focal bacterial infections are often difficult to treat due to the rapid emergence of antibiotic-resistant bacteria, high risk of relapse, and severe inflammation at local lesions. To address multidrug-resistant skin and soft tissue infections, a bacteria-absorbing sponge was prepared to involve a "trap-and-kill" mechanism. The system describes a guanidinium-rich lipopeptide functionalized lyotropic liquid-crystalline hydrogel with bicontinuous cubic networks. Amphiphilic lipopeptides can be spontaneously anchored to the lipid-water interface, exposing their bacterial targeting sequences to enhance antibacterial trapping/killing activity. Computational simulations supported our structural predictions, and the sponge was confirmed to successfully remove ∼98.8% of the bacteria in the medium. Release and degradation behavior studies indicated that the bacteria-absorbing sponge could degrade, mediate enzyme-responsive lipopeptide release, or generate ∼200 nm lipopeptide nanoparticles with environmental erosion. This implies that the sponge can effectively capture and isolate high concentrations of bacteria at the infected site and then sustainably release antimicrobial lipopeptides into deep tissues for the eradication of residual bacteria. In the animal experiment, we found that the antibacterial performance of the bacterial-absorbing sponge was significant, which demonstrated not only a long-term inhibition effect to disinfect and avoid bacterial rebound, but also a unique advantage to protect tissue from bacterial attack. Host defense peptides/peptidomimetics (HDPs) have shown potential for the elimination of focal bacterial infections, but the application of their topical formulations suffers from time-consuming preparation processes, indistinctive toxicity reduction effects, and inefficient bacterial capture ability. To explore new avenues for the development of easily prepared, low-toxicity and high-efficiency topical antimicrobials, a guanidinium-rich lipopeptide was encapsulated in a lyotropic liquid-crystalline hydrogel (denoted as "bacteria-absorbing sponge") to achieve complementary superiorities. The superior characteristic of the bacteria-absorbing sponge involves a "trap-and-kill" mechanism, which undergoes not only a long-term inhibition effect to disinfect and avoid bacterial rebound, but also effective bacterial capture and isolating action to confine bacterial diffusion and protect tissues from bacterial attack. [Display omitted] [ABSTRACT FROM AUTHOR]

A novel portable conductive system of hydroxylated fullerene (TEGs-C 60) embedded on the deep eutectic solvent (DES, choline chloride/malic acid)-agarose gel was developed for on-demand curation with skin contact. It has been found with better elasticity, conductivity and thermal stability than agarose hydrogel. Especially, the electro-responsive drug releasing amount on the skin of mice and live rabbits through small batteries was proved to be 4–5 times of those without electrical stimulation, which reached the level of clinic daily dosage. Meanwhile, it also showed good biocompatibility and much higher antibacterial rate against S. aureus (78.67 ± 0.80 %) together with E. coli (92.08 ± 1.50 %) than those of commercial chitosan gel. The new electrical "switch" gel system provided an effective and useful development strategy for advanced drug delivery. [Display omitted] [ABSTRACT FROM AUTHOR]

Dissolving microneedles (DMN) have been studied as a drug delivery system to enhance the transport of drug molecules across the skin with almost no pain. However, the poor dissolving ability of microneedles in the skin and low drug loading have limited their potential application. The aim of this study was to develop a novel dissolving microneedle system with improved dissolving ability for the delivery of poorly water soluble contraception drug, levonorgestrel (LNG). Chitosan and beta-sodium glycerophosphate (β-GP) were incorporated in the formulation of microneedles. It was found that 69.32 ± 4.23% of the microneedles penetrated through the skin and dissolved within the first 2 h, which was almost 2-fold higher than that of the conventional microneedles. In addition, drug loading was significantly increased by packaging LNG into the molecules of hydroxypropyl beta cyclodextrin (HP-β-CD) to form LNG-HP-β-CD inclusion compounds. The use of chitosan and β-GP together with HP-β-CD inclusion compounds was shown to enhance the bioavailability of LNG transdermally. This novel DMN system resulted in a similar pharmacokinetic profile as that following oral administration. In addition to similar C max and AUC values, drug concentrations in the blood were more consistent following the DMN in comparison to oral administration. [ABSTRACT FROM AUTHOR]

The purpose of this research was to prepare emulsions stabilized by mixed proteins to achieve excellent storage stability and superior functional properties. The emulsions (O/W) with uniform nanoscale droplets (∼250 nm, polydispersity index < 0.2) were stabilized by mixed sodium caseinate (SC) and soy protein isolate (SPI) and produced through high pressure homogenization. Characteristics of the emulsions were evaluated by Dynamic Light Scattering (DLS), Nanoparticle Tracking Analysis (NTA), Transmission Electron Microscopy (TEM), Rheometer and Turbiscan Lab analyzer. The stabilization mechanism was preliminarily investigated by studying the influences of pH, NaCl and SDS solutions on the droplet size, with the application of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). It was found that both flexible protein SC and rigid globular protein SPI were adsorbed on the oil-water interface while some free protein molecules dissolved in the aqueous phase. Electrostatic repulsion and steric stabilization were contributed to the system stability. The retention ratio of vitamin A palmitate was above 93% after three months of storage at room temperature, which demonstrated the protection efficiency of the emulsion was excellent. This work showed a significant promise to develop nutritional products with satisfactory storage stability and physiological benefits. [ABSTRACT FROM AUTHOR]

• A novel flunixin meglumine ODT (Test) was prepared utilizing hot-melt extrusion and D-optimal mixture design. • Test had similar pharmacokinetic behavior to HAIYANSHU® but a better taste-masking effect. • This study provides a new formulation of flunixin meglumine for potential clinical use. Flunixin meglumine (FM) is a nonsteroidal anti-inflammatory drug limited by irritation of the respiratory tract and mucosa in veterinary tissue. This study aimed to develop a taste-masked FM solid dispersion (SD) by hot-melt extrusion (HME) and formulate an orally disintegrating tablet (ODT) with selected excipients by direct compression. Eudragit® E PO was chosen as the matrix, and HME parameters were optimized: extrusion temperature, 135℃; screw speed, 100 rpm; and drug loading, 20%. Characterization techniques proved that FM was rendered amorphous in the HME extrudate. In vitro dissolution studies showed that FM SD released significantly slower than the corresponding physical mixture in artificial saliva. Excipients were selected based on compression formability, disintegration, and solubility. A D-optimal mixture design was used to optimize the composition: 25% FM SD, 18.75% microcrystalline cellulose, 52.5% mannitol, 3.75% low-substituted hydroxypropyl cellulose, and 1% magnesium stearate. Taste-masked FM ODT had a tensile strength of 0.7 ± 0.01 MPa and a disintegration time of 17.6 ± 0.1 s. E-tongue and E-nose analysis showed that FM ODT had a better taste-masked effect than commercial granules. Finally, a pharmacokinetic study proved that the main pharmacokinetic parameters of FM ODT were not significantly different from those of commercial granules, which indicated that these formulations had similar pharmacokinetic behaviours in beagles. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: A method to prepare wide-band reflection cholesteric liquid crystals (CLCs) films by thermally induced diffusion of dye was proposed. Due to the greatly enhanced UV intensity gradient formed by thermal diffusion of dye, the pitch gradient was formed and fixed after the process of photoinduced polymerization and diffusion of CLC monomers. Using this method, the prepared CLCs film can reflect circularly polarized light over a broad wavelength range of 750–2400nm. The pitch gradient of the CLC film was observed by scanning electron microscopy (SEM). In addition, the influence of dye concentration, thermal diffusion time and thermal diffusion temperature on the consequent pitch gradient was systemically studied. [Copyright &y& Elsevier]