Polydopamine-Based Nanoparticles for Safe Sunscreen Protection Factor Products with Enhanced Performance

Abstract

Excessive exposure to ultraviolet light (UV) can damage skin cells and cause skin cancer. Applying sunscreen that blocks both UVA and UVB is recommended before going outside. An ideal sunscreen should not come off, penetrate the bloodstream, or cause health risks, while also remaining effective at blocking UV rays. Herein, we focused on sunscreen applications based on polydopamine (PDA) nanoparticles, an artificial melanin material. Various sizes of nanoparticles were fabricated using a spontaneous oxidation reaction with the dopamine monomer to sodium hydroxide (DA/NaOH) molar ratios of 1:0.2 to 1:1. The monodisperse and spherical PDA nanoparticles with sizes ranging from 59.5 to 659.1 nm showed monotonic broadband UV−vis absorption. PDA2 (molar ratio of DA/ NaOH 1:0.8) presented the highest UVB absorption (290−320 nm) and a sun protection factor boosted by approximately 50% compared to that of the original base formulation. When the particle size was larger than 150 nm, the results from X-ray photoelectron spectroscopy and confocal spectroscopy showed that the surface functionality of the synthesized PDA nanoparticles that was dominated with hydroxyl groups induced their adherence to the stratum corneum after 24 h of incubation. The nanoparticles were biocompatible with human keratinocytes (HaCaT), that is, direct interactions between the PDA particles and HaCaT cells did not cause any cell damage. Results from in vitro photoprotection ability suggested that PDA nanoparticles could protect the cells from UVA irradiation in terms of membrane protection, reactive oxygen species reduction, and cell viability recovery. Interestingly, the results obtained from the bacterial reverse mutation and in vitro skin irritation tests indicated that the nanoparticles did not induce mutagenicity or irritate skin cells. Our findings provide a promising approach for the synthesis of PDA nanoparticles as a safe sunscreen component.

Nonblinking Core–Multishell InP/ZnSe/ZnS Quantum Dot Bioconjugates for Super-resolution Imaging

“…Simultaneously, we obtained a lysosome size of 351 nm by analyzing the wide-field and MSIM plot-line profile. These results are consistent with previous reports in the literature . Therefore, the InP/ZnSe/ZnS QDs can serve as excellent fluorescent probes for SR MSIM imaging applications in fixed and living cells.…”

“…These results are consistent with previous reports in the literature. 37 Therefore, the InP/ZnSe/ ZnS QDs can serve as excellent fluorescent probes for SR MSIM imaging applications in fixed and living cells.…”

ZIF-8 integrated with polydopamine coating as a novel nano-platform for skin-specific drug delivery

“…55,56,71 The order of the penetration depth was ZIF-8@PDA, ZIF-8, and solution, which might be attributed to their contribution to the follicular delivery in the same order. 25,32,72,73 As for the intercellular route, it was involved in the skin penetration of all the groups, among which the solution solely relied on this route, and ZIF-8 was observed with the most striking effect. The dependence of this route might be related to their capacity of drug release, particle size, and interaction with the intercellular lipids.…”

Melanin for Photoprotection and Hair Coloration in the Emerging Era of Nanocosmetics

“…Indeed, melanin, other than being an excellent photoprotective agent, has also high biocompatibility and antioxidant activity, summarizing all the requirements of a proper solar filter. PDA NPs are usually studied as solar filters, as described in the paper of Supanakorn and co-workers [ 76 ]. Their nanoparticles were produced through spontaneous oxidation reactions between a dopamine monomer (DA) and sodium hydroxide (NaOH) ( Figure 2 ).…”