β-cyclodextrin in personal care formulations: role on the complexation of malodours causing molecules

Investigating the prilling/vibration technique to produce gastric-directed drug delivery systems for misoprostol

Prilling/vibration technique to produce oral microcapsules was explored to achieve local delivery of misoprostol (MIS), a prostaglandin E1 analogue indicated for the treatment of gastric-duodenal ulcers, at the gastric mucosa. To improve MIS chemical stability and reduce its associated systemic side effects, drug delivery systems were designed and developed as microcapsules consisting of a core of sunflower oil and MIS (Fs6 and Fs14) or a MIS complex with hydroxypropyl-beta-cyclodextrin (HP-β-CD) (Fs18), confirmed by specific studies, and a polymeric shell. The produced microcapsules showed high encapsulation efficiencies for those with MIS solubilized in sunflower oil (>59.86 %) and for the microcapsules with MIS/HP-β-CD (97.61 %). To demonstrate the ability of these systems to deliver MIS into the stomach, swelling and drug release experiments were also conducted in simulated gastric fluid. Among the three formulations, FS18 showed gastric release within 30 min and was the most advantageous formulation because the presence of the MIS/HP-β-CD inclusion complex ensured a greater ability to stabilise MIS in the simulated gastric environment. In addition, these new systems have a small size (<540 µm), and good flow properties and the dose of the drug could be easily adapted using different amounts of microcapsules (flexibility), making them a passepartout for different age population groups.

Pickering Emulsion Stabilized by β-Cyclodextrin and Cinnamaldehyde/β-Cyclodextrin Composite

A Pickering emulsion was prepared using β-cyclodextrin (β-CD) and a cinnamaldehyde (CA)/β-CD composite as emulsifiers and corn oil, camellia oil, lard oil, and fish oil as oil phases. It was confirmed that Pickering emulsions prepared with β-CD and CA/β-CD had good storage stability. The rheological experiments showed that all emulsions had G' values higher than G″, thus confirming their gel properties. The results of temperature scanning rheology experiments revealed that the Pickering emulsion prepared with β-CD and CA/β-CD composites had high stability, in the range of 20-65 °C. The chewing properties of Pickering emulsions prepared by β-CD and corn oil, camellia oil, lard, and herring oil were 8.02 ± 0.24 N, 7.94 ± 0.16 N, 36.41 ± 1.25 N, and 5.17 ± 0.13 N, respectively. The chewing properties of Pickering emulsions made with the CA/β-CD composite and corn oil, camellia oil, lard, and herring oil were 2.51 ± 0.05 N, 2.56 ± 0.05 N, 22.67 ± 1.70 N, 3.83 ± 0.29 N, respectively. The texture properties confirmed that the CA/β-CD-composite-stabilized-emulsion had superior palatability. After 28 days at 50 °C, malondialdehyde (MDA) was detected in the emulsion. Compared with the β-CD and CA + β-CD emulsion, the CA/β-CD composite emulsion had the lowest content of MDA (182.23 ± 8.93 nmol/kg). The in vitro digestion results showed that the free fatty acid (FFA) release rates of the CA/β-CD composite emulsion (87.49 ± 3.40%) were higher than those of the β-CD emulsion (74.32 ± 2.11%). This strategy provides ideas for expanding the application range of emulsifier particles and developing food-grade Pickering emulsions with antioxidant capacity.

Lactoferrin-Derived Peptides as a Control Strategy against Skinborne Staphylococcal Biofilms

Coagulase-negative staphylococci (CoNS) widely colonize the human skin and play an active role in host defense. However, these bacteria may cause malodours and increase infection incidence rate in immune-compromised patients and individuals with catheters and implants. CoNS spreading is favored by biofilm formation that also promotes the release of virulence factors and drug resistance. Biofilm control or eradication by antimicrobial peptides (AMPs) represents an attractive strategy which is worth investigating. In this work, bovine lactoferrin (BLF) hydrolysate (HLF) was in vitro evaluated for its antimicrobial and antibiofilm activities against skin-related coagulase negative and positive staphylococci. Despite a minimal inhibitory concentration (MIC) recorded for HLF ranging from 10 to more than 20 mg/mL, a minimal biofilm inhibitory concentration (MIBC) equal to 2.5 mg/mL was found for most target strains. Conversely, MIBC values referred to the individual peptides, LFcinB or LFmpin (herein purified and identified) were significantly lower. Finally, the application of 2.5 mg/mL HLF solution by dipping and spraying on biofilm-attached glass surfaces also caused a high biofilm eradication rate depending on the incubation time, thus attracting interest for future applications in cosmetic formulation for skin care.

Thiolated polymers: Bioinspired polymers utilizing one of the most important bridging structures in nature

Thiolated polymers designated "thiomers" are obtained by covalent attachment of thiol functionalities on the polymeric backbone of polymers. In 1998 these polymers were first described as mucoadhesive and in situ gelling compounds forming disulfide bonds with cysteine-rich substructures of mucus glycoproteins and crosslinking through inter- and intrachain disulfide bond formation. In the following, it was shown that thiomers are able to form disulfides with keratins and membrane-associated proteins exhibiting also cysteine-rich substructures. Furthermore, permeation enhancing, enzyme inhibiting and efflux pump inhibiting properties were demonstrated. Because of these capabilities thiomers are promising tools for drug delivery guaranteeing a strongly prolonged residence time as well as sustained release on mucosal membranes. Apart from that, thiomers are used as drugs per se. In particular, for treatment of dry eye syndrome various thiolated polymers are in development and a first product has already reached the market. Within this review an overview about the thiomer-technology and its potential for different applications is provided discussing especially the outcome of studies in non-rodent animal models and that of numerous clinical trials. Moreover, an overview on product developments is given.

Host–guest complexation of ionic liquid with α- and β-cyclodextrins: a comparative study by 1H-NMR, 13C-NMR and COSY

The inclusion complexation of 1-butyl-3-methylimidazolium octylsulphate [Bmim][OS] with host α- and β-cyclodextrins (CDs) has been explored by ¹H NMR, ¹³C NMR and COSY methods. The insertion of a guest molecule into the cavity of CD is clearly reflected by changes in ¹H-NMR and ¹³C-NMR chemical shift values and COSY NMR suggest that both H-bonding and electrostatic interactions involved to the complexation.