Characterization and Evaluation of Poly(ε-caprolactone) Nanoparticles Containing 2-Ethylhexyl-p-Methoxycinnamate, Octocrylene, and Benzophenone-3 in Anti-Solar Preparations

Abstract

Ultraviolet radiation can bring both harm and benefits to human health. Among those harms are erythemas, photosensitivity, photoaging, and the most worrying, skin cancer. Nanoencapsulation of sunscreen agents (SA) by using a biocompatible and biodegradable polymer such as poly(epsilon-caprolactone) (PCL) is advantageous as it increases the retention of UV absorbers in the skin, avoids systemic absorption, and consequently, improves water resistance and stability of the preparation. The aim of this work is to develop, characterize, and study the encapsulation of 3 different SA: 2-ethylhexyl-p-methoxycinnamate, benzophenone-3, and octocrylene in PCL nanoparticles (Nps). Nps were prepared by the solvent emulsification and evaporation method. The process yield was calculated, and the Nps were characterized in terms of size, polydispersity index (PI), morphology, zeta potential (ZP), encapsulation efficiency (EE) (%), and sunscreen agent content (SAC). The final formulations were submitted to the hen's egg test-chorioallantoic membrane (HET-CAM), chorioallantoic membrane-trypan blue staining (CAM-TBS), red blood cell (RBC), Draize tests, in vitro release, in vitro sun protection factor (SPF), UVA protection factor (PF-UVA), and photostability. All the Nps were in the nanometric scale. PI showed monodisperse systems. ZP became more negative as the Np were lyophilized and were added to the formulations. EE varied from 84 to 90%. The SAC went from 44 to 65 microg of sunscreen agents by milligram of Np. The process yield went from 60 to 76%. Nps were predominantly spherical and elliptical forms. The addition of Np diminished the release of the SA. The SPF increased with Np presence and helped to maintain the PF-UVA after irradiation. The HET-CAM assay evaluated the formulation as slightly irritant, CAM-TBS and RBC tests as non irritant, and the Draize test as moderately irritant.

Preparation of PMMA Nanoparticles Loaded with Benzophenone‐3 through Miniemulsion Polymerization

“…Benzophenones have been used commercially as sun filters since the late fifties. Particularly, benzophenone‐3 (BZ‐3) (2‐hydroxy‐4‐methoxybenzophenone or oxybenzone) is the commonest compound of this class 10. BZ‐3 is a lipophilic compound that is capable to absorb and dissipate UVA radiation very efficiently, although with lower intensity in the UVB region 11.…”

Controlled drug delivery for glaucoma therapy using montmorillonite/Eudragit microspheres as an ion-exchange carrier

“…32 Briefly, fertilized hen's eggs were incubated in the horizontal position to ensure correct positioning of the embryo (away from the CAM) at 37°C±0.5°C and 40%±5% relative humidity for 9 days. 33 On the 10th day, the section of egg shell above the airspace was removed and several drops of saline solution were added onto the shell membrane with a pipette. Then, the inner membrane was carefully removed to expose the CAM without damaging the underlying CAM.…”

Understanding engineered nanomaterial skin interactions and the modulatory effects of ultraviolet radiation skin exposure

“…155,156 To hinder agglomeration and to help protect skin from contacting the potential phototoxic TiO 2 and ZnO metal oxide core, the particles are usually coated with, for example, silica, aluminum hydroxide, or methicone. 145,157,158 While much is understood about the formulation of UVR-protective cosmetics and how to control the photoactive properties of eNM, very little is understood quantitatively or mechanistically about the penetration of nanoscale TiO 2 and ZnO or other eNM through UVR-exposed skin. This has spurred increasing efforts over the past 5 years to examine this specific question.…”

“…By far the most important eNM to be studied in the context of UVR skin exposure is that of ZnO and TiO 2. Other eNM types that have been studied on UVR‐exposed skin include fluorescent QDs, which facilitate tissue tracking, polymer nanoparticles, polymer‐coated platinum nanoparticles, and iron oxide nanoparticles for improved UVR protection. The interest in nanoparticle‐based UVR‐protective lotions stems from the fact that many common organic UVR filters, such as 2‐ethylhexyl 4‐methoxy cinnamate and 3‐benzylidene camphor, can penetrate through skin and they have been detected in urine and breast milk .…”

“…Generally, the anatase form of TiO 2 displays higher photoactivity, ROS production, and cytotoxicity than the rutile form, which is preferred for use in UVR‐protective cosmetics . To hinder agglomeration and to help protect skin from contacting the potential phototoxic TiO 2 and ZnO metal oxide core, the particles are usually coated with, for example, silica, aluminum hydroxide, or methicone . While much is understood about the formulation of UVR‐protective cosmetics and how to control the photoactive properties of eNM, very little is understood quantitatively or mechanistically about the penetration of nanoscale TiO 2 and ZnO or other eNM through UVR‐exposed skin.…”