Percutaneous absorption of organic sunscreens

The increased awareness of protection against skin cancer has led to a rise in the use of topically applied chemical sunscreen agents. There is a concern about the systemic absorption of organic filters in sunscreen formulations. The present study briefly reviews theoretical models for the prediction of the percutaneous penetration of the organic molecules and the accepted methods for the in vitro and in vivo evaluations of the penetration. The influence of the vehicle and the formulation viscosiy on the penetration of sunscreens are examined. The development of novel methods for the minimization of sunscreen absorption is also discussed. © 2006 Blackwell Publishing

Skin care formulations and lipid carriers as skin moisturizing agents

Skin care formulations have evolved as the interaction of health and beauty products for the skin. Their benefits are based on the combination of cosmetic active ingredients and targeted application. Cosmetic actives have been used in novel formulations for decades (sunscreens, anti-aging treatments, etc.), but the problems with their low solubility, low penetration, and physicochemical instability when applied to the skin have yet to be solved. One way to circumvent these shortcomings is to use lipid carriers, which are known to play an important role in the solubility of poorly soluble compounds by facilitating skin permeation and improving stability. This review addresses recent advances in skin care products that use novel nanotechnology-based lipid systems (liposomes, solid lipid nanoparticles, etc.) to deliver moisturizing cosmetic actives and improve product efficacy. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

Development and validation of an ion-pair RP-HPLC method for the determination of oligopeptide-20 in cosmeceuticals

Oligopeptide-20 is a growth-factor mimicking peptide used in cosmeceuticals. This article describes the development and validation of an ion-pair reversed-phase liquid chromatography method that allows, after liquid-liquid extraction, the quantification of oligopeptide-20 in cosmetic creams. Chromatographic separation was achieved on a cyanopropyl Hypersil analytical column (100mm×2.1mm i.d., 5μm particle size), using a mobile phase of acetonitrile-heptafluorobutyric acid (pH=2.5, 9.0mM) (70:30, v/v) containing 0.045% diethylamine at a flow rate of 0.50mLmin -1. Ultraviolet (UV) spectrophotometric detection at 225nm was used. The method had linear calibration curve over the range 1.35-4.95μgmL -1 for oligopeptide-20. The intra- and inter-day RSD values were less than 3.3%, while the relative percentage error, %E r, was less than 1.9. The developed method was applied successfully to the quality control of a cosmetic cream containing 0.003% (w/w) oligopeptide-20. © 2011 Elsevier B.V

New aza-thioxanthones: Synthesis and cytotoxicity

A new series of aza-thioxanthones has been synthesized and tested for in vitro cytotoxicity in a number of cell lines. Almost all the compounds were found to exhibit significant cytotoxicity in the leukemic MOLT-4 line, whereas some of them showed pronounced activity in the non-small lung cancer cell line HOP-92

New pyrazole-annulated azathioxanthenes as potential intercalators: Synthesis and structure elucidation

As part of our program aiming at developing efficacious intercalating agents, a new series of pyrazole-annulated azathioxanthenes 15a-e has been synthesized. Structure elucidation of 15a-e was based on their spectral data and especially the NOESY nmr spectrum of analog 15a

Synthesis and biological evaluation of indole containing derivatives of thiosemicarbazide and their cyclic 1,2,4-triazole and 1,3,4-thiadiazole analogs

New indolic derivatives of thiosemicarbazides and some cyclic 1,2,4- triazol-5-thione analogs were synthesized. The newly synthesized compounds as well as some indole containing thiosemicarbazides, 1,2,4-triazoles and 1,3,4- thiadiazoles, which have been reported previously, were investigated for antimicrobial, antifungal and antiphage activity. Certain thiosemicarbazide derivatives and the corresponding cyclic 1,2,4-triazole analogs showed selective antimicrobial or antifungal activity, while they lack any antiphage activity. Antiphage activity was detected for one compound, bearing the 1,3,4-thiadiazole nucleus. The selectively active compounds cover a wide range of lipophilicity. Structure-activity relations show a remarkably similarity in the antimicrobial and antifungal behaviour of the thiosemicarbazides and their cyclic triazo-thien-5-yl analogs, while α- naphtyl substitution in the non indolic portion of the molecule is favorable. C5 substitution on the indolic nucleus may also be critical for selective activity

The efficacy study of the combination of tripeptide-10-citrulline and acetyl hexapeptide-3. A prospective, randomized controlled study

Background: Bioactive peptides have beneficial effects on the skin. Objective: We investigated to evaluate the effect of acetyl hexapeptide-3 and tripeptide-10 citrulline and the possible synergism between these two peptides. Methods: Twenty-four healthy volunteers were randomized to receive combination of acetyl hexapeptide-3 with tripeptide-10 citrulline (Group G1), tripeptide-10 citrulline (Group, G2), acetyl hexapeptide-3 (Group G3), or neither peptide (Group G4) for 60 days. Skin properties evaluated included skin microtopography, parameters cR2 and cR3, and transepidermal water loss (TEWL) using a skin visioscan and a tewameter, respectively. Results: After 20 days, the measurements between G1 and G2 groups (cR2 P=.045, cR3 P=.044), G2 and G3 groups (cR2 P=.017, cR3 P=.017), G3 and G4 groups (CR2 P=.022), and G2 and G4 groups (cR3 P=.028) from baseline were significant. After 60 days, measurements between groups G1 and G3 (cR2 P=.016, cR3 P=.025), groups G2 and G3 (cR2 P=.044, cR3= P=.044), and groups G1 and G4 (cR2 P=.025) were significant. After 20 days, changes in TEWL between groups G1 and G3 (P=.03), groups G2 and G3 (P=.045), and groups G3 and G4 (P=.025) were significant. After 40 days, changes between groups G2 and G3 (P=.028) and groups G3 and G4 (P=.01) from baseline were significant. Conclusion: Our results confirm the antiwrinkle activity of acetyl hexapeptide-3. A significant decrease in TEWL with acetyl hexapeptide-3 treatment is observed. We provided clinical evidence for the antiwrinkle efficacy of tripeptide-10 citrulline and possibly TEWL. The underlying mechanism by which these two peptides can act synergistically was not clear in this study. © 2017 Wiley Periodicals, Inc