Sunscreen Properties Research Articles

Evaluation of drug-likeness and ADME properties of sunscreens and preservatives using reversed-phase thin layer chromatographic retention data and calculated descriptors

RP-18 TLC chromatography was used to evaluate the pharmacokinetic properties (volume of distribution, VD; plasma protein binding, %PPB; the ability to cross the blood-brain barrier expressed as log PS and log BB) of several cosmetic raw materials – sunscreen and preservatives. The majority of these compounds are intended for topical use on skin and their drug-likeness and the ability to cross biological barriers are undesired. The retention parameters RM0, S, PC1 and RM75 % obtained for mobile phases containing six organic modifiers (methanol, acetonitrile, THF, acetone, dioxane, DMF) were used as the sole descriptors or combined with calculated physicochemical properties (PSA, MW, VM) of studied compounds.The chromatographic parameters considered in this study are, generally speaking, good predictors of the compounds’ pharmacokinetic properties VD, %PPB and log PS. RM75 % and the novel parameters derived from it (RM75 %/MW and RM75 %/VM) can be considered time- and cost-effective alternatives to the chromatographic parameters obtained by extrapolation or interpolation methods. In the case of some pharmacokinetic properties investigated in this study additional descriptors (PSA) have a significant influence on the quality of correlations.

Photoprotection: Key Concepts, Current Status, and Special Patient Groups

This article aims to help non-dermatologist medical professionals regarding the current status of photoprotection so that they may be better positioned to advise and respond to their patients. While the effects of solar radiation have long been known to include sunburn and skin cancers derived from ultraviolet B radiation, advances in knowledge now recognise the relevance of ultraviolet A, visible, and infrared light as significant contributors to skin damage. Effects on the skin range from aesthetic signs of photoageing, which accumulate with daily exposure, to skin cancers. Despite some trends towards increased awareness of the dangers of solar radiation and the need for photoprotection, behaviours still put people at risk and sun protection is suboptimal. In addition to the general population, certain population groups require special consideration depending on their work environment, lifestyle, and health status. The efficacy and cosmetic properties of sunscreens have improved greatly and should help to improve compliance with recommended use, but a multifaceted approach focussed on education and enabling uptake of recommendations is essential.

Photoprotective Activity of Plectranthus amboinicus Extracts and HPLC Quantification of Rosmarinic Acid

Overexposure to sunlight has harmful effects on the skin and can cause erythema and skin cancer. Photoprotective agents are important for preventing exposure to sunlight and are present in the composition of sunscreens. Globally, the use of filters based on natural products has gained interest in scientific studies; in addition to their sunscreen properties, these products demonstrate antioxidant, healing, and moisturizing activity. These favor adequate sun protection due to the wide spectrum of activities and are environmentally friendly. Plectranthus amboinicus (Lour.) Spreng., Lamiaceae, is used in traditional medicine to treat several conditions and is commonly known as “hortela-da-folha-grossa” in Brazil. This species presents phenolic compounds, including rosmarinic acid, and has been studied for photoprotection and antioxidant activity. The aim of this study was to evaluate the photoprotection potential and antioxidant activity, and to develop analytic methodology for extract standardization and validation. Thus, maximum absorbance, sun protection factor, DPPH radical scavenging activity, and total phenolic contents of P. amboinicus crude ethanolic extract were determined, and an HPLC analytical methodology was developed and validated to quantify rosmarinic acid. Analyses revealed that the extract presented good photoprotection (SPF = 12.63), promising antioxidant activity (EC50 = 112.39 μg/ml), total phenolic content (142.39 ± 1.12 mg GAE/g), and rosmarinic acid concentrations (22.5 μg/ml). In addition, an HPLC analytical method was validated for marker quantification. These results show that the extract has potential photoprotective and antioxidant activity, and this favors the isolation of a final product with protective characteristics that encompass broad spectrum action and biological protection.

Sunscreen Properties of Marl.

The physicochemical and sunscreen properties of marl as a function of particle size were investigated. The research findings established that the marl under investigation consisted of more than 95% calcium carbonate (CaCO3). The particles of marl inspected under a scanning electron microscope were calcite, which is the stable polymorph of CaCO3, with a rhombohedral structure. The particle size classification by the sieving method showed that grinding using a ball mill could downsize the marl particles by 2 to 3 times, reaching below 15 µm on average. Marl particles showed a tendency to reflect ultraviolet A (UVA) rays rather than UVB rays and a possibility to steadily absorb both UVAII and UVAI. Finer particles obtained after a longer grinding process demonstrated higher efficacy regarding UV reflection and absorption properties. The 3 wt.% marl displayed a sun protection factor (SPF) value of 1 to 2. However, marl demonstrated a good ability to protect against radiation over a broad spectrum range with a critical wavelength above 370 nm. The addition of marl in the formulation containing avobenzone and octinoxate had a positive synergistic effect because the marl was able to increase the UV absorbance efficacy (based on the area under the curve (AUC) value) and SPF value of the cream. Furthermore, it was also discovered that the added marl powder could slow the decrease in UV protection efficacy of the products in terms of the AUC calculated from the absorbance profile after exposure to simulated UV rays with an amplitude range of 10 J/cm2 to 40 J/cm2 for 30 min, which was similar to the results obtained from octocrylene and bemotrizinol.

Application of an Easy-to-Perform High-Energy and Low-End Visible Light Transmittance Method and the Influence of Tinted Sunscreens on High-Energy/Low-End Visible Light Transmittance and Infrared Protection

Background: About 50% of the sun’s radiation arriving on earth is visible light (VIS). For a long time, its effects on human health have not been fully investigated. But recently, the influence of VIS has gained more attention, especially regarding skin physiology. Studies showed various effects, many of them harmful, comparable to UV radiation. As a result, there are now a few sunscreens commercially available which claim protection against VIS. The question of whether protection is necessary is still much discussed. Aims: The objective of this study was to develop an easy-to-perform high-energy visible (HEV) and low-end visible (LEV) light transmittance method to determine the direct VIS protection of sunscreens and other cosmetic samples. Furthermore, the influence of the brightness of the tested products on the HEV, LEV, and infrared A protection was investigated. Methods: An experimental setup consisting of a light source, a VIS-transmissible filter system, and a sensor unit was built to measure the direct VIS protection of sunscreens and other daily skin care products in two ranges of the VIS area. For a closer look, the brightness of the samples was evaluated by photometric assessment. Results/Conclusion: The experimental setup could be validated. It could be demonstrated for the first time that there is a strong positive linear correlation between transmittance and brightness of tinted sunscreen and daily skin care products with sunscreen properties in the HEV, LEV, and infrared A range. However, tinted samples worked best in the blue light region, and the higher the wavelength range, the lower the protection.

Sunscreen Application, Safety, and Sun Protection: The Evidence.

Recently in Canada, there has been an effort to create consistent messaging about sun safety as there is a lack of up-to-date evidence-based guidelines regarding sun-protection measures. This review aimed to provide updated, evidence-based recommendations on sunscreen application, safety, and sun protection regarding the following topics for which there is clinical uncertainty: physical barriers, sunscreen properties, sunscreen application, and risk-benefit analysis.

Validation of a predictive method for sunscreen formula evaluation using gene expression analysis in a Chinese reconstructed full‐thickness skin model

This study aimed to establish a predictive invitro method for assessing the photoprotective properties of sunscreens using a reconstructed full-thickness skin model. A full-thickness skin model reconstructed with human fibroblasts and keratinocytes isolated from Chinese skin was exposed to daily UV radiation (DUVR). We examined the transcriptomic response, identifying genes for which expression was modulated by DUVR in a dose-dependent manner. We then validated the methodology for efficacy evaluation of different sunscreens formulas. The reconstructed skin model was histologically consistent with human skin, and upon DUVR exposure, the constituent fibroblasts and keratinocytes exhibited transcriptomic alterations in pathways associated with oxidative stress, inflammation and extracellular matrix remodelling. When used to evaluate sunscreen protection on the model, the observed level of protection from UV-induced gene expression was consistent with the corresponding protection factors determined clinically and allowed for statistical ranking of sunscreen efficacy. Within this study we show that quantification of gene modulation within the reconstructed skin model is a biologically relevant approach with sensitivity and predictability to evaluate photoprotection products.

Determination of Sun Protection Factor and Antioxidant Properties of Cream Formulation of Kencur (Kaempferia galanga L) and Temu Kunci (Boesenbergia pandurata (Roxb.) Schlecht) Rhizomes Extract

Kencur (Kaempferia galanga, L.) rhizome contain ethyl-p-methoxycinnamate (EPMS) which has sunscreen properties. Temu kunci (Boesenbergia pandurata (Roxb) Schlecht) rhizome contains flavonoid and essential oils with radical scavenging properties. The aims of this study were to obtain the optimum physical properties of sunscreen and antioxidant cream and to compare the sun protection factor (SPF) values and antioxidant activity of kencur and temu kunci rhizomes extract before and after formulated. This research used Simplex Latice Design (SLD) model with 2 components of kencur extract and temu kunci extract. Based on the SLD model obtained optimum formula design, then the SPF values and antioxidant activity were studied by UV spectrophotometric method and DPPH method respectively. Based on SLD model obtained optimum formula that containing kencur : temu kunci extract 80%:20% (formula A) and 70%:30% (formula B). The SPF values of kencur extract, formula A and formula B were 4.505, 5.024 and 4.511 respectively. Antioxidant activity showed that the IC50 of formula A, formula B, temu kunci extract, BHT and Vitamin E were 109.15 μg/mL, 95.23 μg/mL, 10.20 μg/mL, 22.33 μg/mL and 8.78 μg/mL respectively. Cream formula A and formula B have optimum physical properties. The SPF value of the optimum formulations were higher than SPF value of kencur extract. Antioxidant activity of that combinations were lower than temu kunci extract, BHT and Vitamin E.

Determination of Sun Protection Factor (SPF) Number of Some Hydroalcoholic Vegetable Extracts

Exposure to sunlight can trigger various biological responses ranging from sun-burn, erythema to skin cancer. Synthetic sunscreen formulations available in market pose variety of adverse effects. Therefore formulation of the herbal sunscreen formulation and evaluation of its sun protection activity is an important aspect in the cosmetic industry. The various herbal agents contain significant sun screen properties which might be useful for formulating herbal creams and lotions. Therefore evaluation of its sun protection activity is an important aspect in the cosmetic industry. The comparative values of the calculated sun protection factor of twelve commonly used vegetables were evaluated using Mansur equation. Hydroalcoholic herbal extracts were obtained and absorbances were recorded between 290-320 nm using UV-Vis spectrophotometer. It was observed that all of the tested herbal extracts showed some UV protection capabilities with hydroalcoholic extract. Hydroalcoholic extract of beet root showed highest SPF i.e. 39.48 while capsicum extract showed lowest i.e. 2.45. These plant herbals can be formulated in the form of cosmetics formulation because of their better acceptability, less irritant nature and also these are less expensive.

Vicenin-2 ameliorates oxidative damage and photoaging via modulation of MAPKs and MMPs signaling in UVB radiation exposed human skin cells

Exposure of ultraviolet (UV) radiation is the major factor from environment to cause erethema, inflammation, photoaging and skin carcinogenesis. Vicenin-2, a bioflavonoid which are isolated from several medicinal plants. The present study was demonstrated the role of vicenin-2 on UVB linked oxidative stress and photoaging signaling in human dermal fibroblasts (HDF). In this study, UVB-irradiation (100 mJ/cm2) significantly elevated the intracellular ROS levels, lipid peroxidation, DNA damage, depletion of antioxidants resulted in apoptotic HDF cells. Interestingly, HDF cells were administrated with vicenin-2, 1 h before UVB-irradiation prevents ROS generation, TBARS, apoptotic changes and DNA damage in HDF. MAPKs and MMP signaling are implicated in oxidative stress and photoaging; these signaling events are considered as photoaging and differentiation. We found that Vicenin-2 prevents over expression of MAPKs (p-ERK1, p-JNK & p-p38), AP-1 and MMPs (MMP-2, 9 & 12) in during the exposure of UVB in HDF cells. These findings conclude that vicenin-2 could be a potential bioactive ingredient to absorb UV photons and protects the dermal cells from the UVB associated oxidative stress and photoaging signaling due to sunscreen properties.

The liquid polyol extracts of camellia seed dregs used in sunscreen cosmetics

Polyol solvents were used to extract Camellia oleifera Abel dregs and sunscreen properties of the extracts were examined in the present paper. The effects of extracts obtained with water and ethanol were compared. This study found that polyols were more efficient at extracting flavonoid glycosides, triterpenoid glycosides, and other polyphenols in the C. oleifera Abel dregs, resulting in a more efficient sunscreen. The polyphenols in the extract had peak absorbance at wavelengths of 254, 280, and 329 nm, the triterpenoid glycosides had a peak at 200–240 nm and the flavonoid glycosides showed a broad range of absorption (at 230–400 nm). The extract obtained with polyol solvent had strong absorption at wavelengths of 200–400 nm. The interaction of the polyol extracts with organic UV-absorbers or inorganic sunscreen agents showed synergic effects and the extract can significantly improve the sunscreen effect of organic UV-absorbers or inorganic sunscreen agents. Therefore, this extract can decrease the amount of organic UV-absorbers and inorganic sunscreen agents used and can increase protection against UVA and UVB. It can be used in maintenance and sunscreen products.

Ultraviolet Protection Properties of Commercial Sunscreens and Sunscreens Containing Zno Nanorods

Zinc oxide nanorods were used as the main ultraviolet agent in the development of sunscreens. Four commercial sunscreens containing organic and inorganic UV agents were studied for their UV performances and SPF determinations. From FESEM and TEM micrographs of ZnO powder, the dominant structure was rod structure with width range 61-70 nm. Sunscreens containing different concentrations of ZnO nanorods were characterized using UV-Vis spectrophotometer and X-ray diffraction (XRD). The absorbance spectra for commercial sunscreens showed a good protection in range of UVB (280-320nm), while sunscreens containing 20-40% (weight percentage) of ZnO nanorods showed a greater UV absorbance in UVA and UVB (280-400 nm). The strong UVA absorbance of ZnO nanorod can offer extra UV protection for commercial sunscreens. The average crystallite sizes of the sunscreen samples calculated from the XRD spectra were in the range 45.27 to 47.36 nm. In vitro sun protection factor (SPF) method was carried out to determine the SPF value of sunscreen specimens. SPF values of sunscreens containing ZnO nanorods were 29.50 to 43.48, whereby these SPF values indicated more than 93% of UVB blocking capability. The SPF values found of commercial sunscreens were slightly different from the SPF values in the product labels. In conclusion, incorporation of ZnO nanorods into sunscreen can greatly enhanced the UV blocking performance of sunscreens.

Improving the Sunscreen Properties of TiO2 through an Understanding of Its Catalytic Properties.

The use of particulate titanium dioxide (TiO2) as an active sunscreen ingredient has raised concerns about potential risks from TiO2-mediated free radical formation. To date, remediation attempts have concentrated on reducing the yield of free radical generation by TiO2 upon sunlight exposure. The problem with this approach is that given the band gap in TiO2, production of radical and the ensuing reactive oxygen species (ROS) is completely normal. Our strategy is based on a nontoxic, biocompatible shell that neutralizes the free radicals by scavenging them with natural antioxidants before they exit the particle. The new lignin@TiO2 composites preserve the scattering and absorption properties of TiO2 because the particles retain their nanoscale dimensions as preferred by the cosmetic industry. Although the target properties for photocatalysis and sun-protection applications are opposite, we argue that exactly the same knowledge is required to optimize either one.

Photoprotective effects of topical ginseng leaf extract using Ultraflo L against UVB-induced skin damage in hairless mice

BackgroundAbnormal activation of matrix metalloproteinases (MMPs) plays an important role in UV-induced wrinkle formation, which is a major dermatological problem. This formation occurs due to the degeneration of the extracellular matrix (ECM). In this study, we investigated the cutaneous photoprotective effects of Ultraflo L treated ginseng leaf (UTGL) in hairless mice. MethodsSKH-1 hairless mice (6 weeks of age) were randomly divided into four groups (8 mice/group). UTGL formulation was applied topically to the skin of the mice for 10 weeks. The normal control group received nonvehicle and was not irradiated with UVB. The UV control (UVB) group received nonvehicle and was exposed to gradient-UVB irradiation. The groups (GA) receiving topical application of UTGL formulation were subjected to gradient-UVB irradiation on 0.5 mg/cm2 [GA-low (GA-L)] and 1.0 mg/cm2 [(GA-high (GA-H)] of dorsal skin area, respectively. ResultsWe found that topical treatment with UTGL attenuated UVB-induced epidermal thickness and impairment of skin barrier function. Additionally, UTGL suppressed the expression of MMP-2, -3, and -13 induced by UVB irradiation. Our results show that topical application of UTGL protects the skin against UVB-induced damage in hairless mice and suggest that UTGL can act as a potential agent for preventing and/or treating UVB-induced photoaging. ConclusionUTGL possesses sunscreen properties and may exhibit photochemoprotective activities inside the skin of mice. Therefore, UTGL could be used as a potential therapeutic agent to protect the skin against UVB-induced photoaging.

Skin Cancer and UV Protection

Abstract The incidence of skin cancer is increasing by epidemic proportions. Basal cell cancer remains the most common skin neoplasm, and simple excision is generally curative. On the other hand, aggressive local growth and metastasis are common features of malignant melanoma, which accounts for 75% of all deaths associated with skin cancer. The primary cause of skin cancer is long exposure to solar ultraviolet radiation (UV-R) crossed with the amount of skin pigmentation and family genetics. It is believed that in childhood and adolescence, 80% of UV-R gets absorbed while in the remaining, 20 % gets absorbed later in the lifetime. This suggests that proper and early photoprotection may reduce the risk of subsequent occurrence of skin cancer. Reducing the exposure time to sunlight, using sunscreens and protective textiles are the three ways of UV protection. Most people think that all the clothing will protect them, but it does not provide full sun screening properties. Literature sources claim that only 1/3 of the spring and summer collections tested give off proper UV protection. This is very important during the summer months, when UV index is the highest. Fabric UV protection ability highly depends on large number of factors such as type of fiber, fabric surface, construction, porosity, density, moisture content, type and concentration of dyestuff, fluorescent whitening agents, UV-B protective agents (UV absorbers), as well as nanoparticles, if applied. For all of these reasons, in the present paper, the results of UV protecting ability according to AS/NZS 4399:1996 will be discussed to show that standard clothing materials are not always adequate to prevent effect of UV-R to the human skin; and to suggest the possibilities for its improvement for this purpose enhancing light conversion and scattering. Additionally, the discrepancy in UV protection was investigated in distilled water as well as Adriatic Sea water.

Safranal-loaded solid lipid nanoparticles: evaluation of sunscreen and moisturizing potential for topical applications.

In the current study, sunscreen and moisturizing properties of solid lipid nanoparticle (SLN)-safranal formulations were evaluated. Series of SLN were prepared using glyceryl monostearate, Tween 80 and different amounts of safranal by high shear homogenization, and ultrasound and high-pressure homogenization (HPH) methods. SLN formulations were characterized for size, zeta potential, morphology, thermal properties, and encapsulation efficacy. The Sun Protection Factor (SPF) of the products was determined in vitro using transpore tape. The moisturizing activity of the products was also evaluated by corneometer. The SPF of SLN-safranal formulations was increased when the amount of safranal increased. Mean particle size for all formulas was approximately 106 nm by probe sonication and 233 nm using HPH method. The encapsulation efficiency of safranal was around 70% for all SLN-safranal formulations. The results conclude that SLN-safranal formulations were found to be effective for topical delivery of safranal and succeeded in providing appropriate sunscreen properties.

Structural elucidation, in vitro antioxidant and photoprotective capacities of a purified polyphenolic-enriched fraction from a saltmarsh plant

In temperate saltmarshes, halophytic plants have to daily protect their internal tissues against sunlight and UV rays. Consequently, they develop adaptive responses such as the synthesis of secondary metabolites, including polyphenols. The present study focused on the biological activities of fractions enriched in polyphenols from Salicornia ramosissima. Three different extracts were obtained by purification processes to concentrate polyphenols: a crude hydroalcoholic extract, and two purified fractions: an ethyl acetate fraction (EAF) and an aqueous fraction. Phenolic and flavonoid contents, antioxidant (DPPH radical-scavenging activity, reducing activity, β-carotene linoleic acid system and the ORAC method) and sunscreen properties (Sun Protection Factor and UVA-Protection Factor) were assessed by in vitro tests. The purification process was effective in increasing phenolic and flavonoid contents as well as antioxidant and sunscreen capacities of the EAF. The EAF appeared to be a broad spectrum UV absorber. The chemical structure of 10 EAF polyphenols was elucidated using 2D NMR and mass spectrometry spectra. Furthermore, a correlation was observed between phenolic composition and biological activity. These findings are encouraging for the future use of S. ramosissima as a potential source of antioxidant and photoprotectant molecules for industrial applications.

Light Conversion and Scattering in UV Protective Textiles

Abstract The primary cause of skin cancer is believed to be a long exposure to solar ultraviolet radiation (UV-R) crossed with the amount of skin pigmentation in the population. It is believed that in childhood and adolescence 80% of UV-R gets absorbed, whilst in the remaining 20% gets absorbed later in the lifetime. This suggests that proper and early photoprotection may reduce the risk of subsequent occurrence of skin cancer. Textile and clothing are the most suitable interface between environment and human body. It can show UV protection, but in most cases it does not provide full sun screening properties. UV protection ability highly depends on large number of factors such as type of fibre, fabric surface and construction, type and concentration of dyestuff, fluorescent whitening agent (FWA), UV-B protective agents, as well as nanoparticles, if applied. Based on electronically excited state by energy of UV-R (usually 340-370 nm), the molecules of FWAs show the phenomenon of fluorescence giving to white textiles high whiteness of outstanding brightness by reemitting the energy at the blue region (typically 420-470 nm) of the spectrum. By absorbing UV-A radiation, optical brightened fabrics transform this radiation into blue fluorescence, which leads to better UV protection. Natural zeolites are rock-forming, microporous silicate minerals. Applied as nanoparticles to textile surface, it scatters the UV-R resulting in lower UV-A and UV-B transmission. If applied with other UV absorbing agents, e.g. FWAs, synergistic effect occurs. Silicones are inert, synthetic compounds with a variety of forms and uses. It provides a unique soft touch, is very resistant to washing and improves the property of fabric to protect against UV radiation. Therefore, the UV protective properties of cotton fabric achieved by light conversion and scattering was researched in this paper. For that purpose, the stilbene-derived FWAs were applied on cotton fabric in wide concentration range without/with the addition of natural zeolite or silicone- polydimethylsiloxane. UV protection was determined in vitro through ultraviolet protection factor. Additionally, the influence to fabric whiteness and hand was researched

Effects of Topical and Dietary Use of Shea Butter on Animals

Shea butter is the fat extracted from the nut of Africa Shea tree (Vitellaria paradoxa). It is used in cosmetic formulations and as a substitute for Cocoa butter in chocolate industries. It is edible and used cooking fat in Africa. The saponifiable fraction of Shea butter is composed primarily of stearic and oleic acids with lesser amounts of palmitic, linoleic and arachidic acids while the unsaponifiable fraction of Shea butter is composed of bioactive substances that are responsible for Shea butter’s medicinal properties. Shea butter is a solid at room temperature and melts at body temperature. It is therefore useful for skin care as it has sun screening properties and acts as an emollient and skin moisturizer. Topical use of Shea butter has also demonstrated anti-aging and anti-inflammatory properties. Dietary intake of Shea butter has hypocholesterolemic effect and reduces serum and organ protein concentrations.

Effects of Oral and Topical Use of the Oil from the Nut of Vitellaria paradoxa

Shea butter is the fat extracted from the nut of Africa Shea tree (Vitellaria paradoxa). It is used in cosmetic formulations and as a substitute for Cocoa butter in chocolate industries. It is edible and used cooking fat in Africa. The saponifiable fraction of Shea butter is composed primarily of stearic and oleic acids with lesser amounts of palmitic, linoleic and arachidic acids while the unsaponifiable fraction of Shea butter is composed of bioactive substances that are responsible for Shea butter’s medicinal properties. Shea butter is a solid at room temperature and melts at body temperature. It is therefore useful for skin care as it has sun screening properties and acts as an emollient and skin moisturizer. Topical use of Shea butter has also demonstrated anti-aging and anti-inflammatory properties. Dietary intake of Shea butter has hypocholesterolemic effect and reduces serum and organ protein concentrations.