Diatomite encapsulated AgNPs as novel hair dye cosmetics: Preparation, performance, and toxicity

Unveiling the Impact of Dyes on Aquatic Ecosystems through Zebrafish - A Comprehensive Review

Dye industry plays an essential role in industrial development, contributing significantly to economic growth and progress. However, its rapid expansion has led to significant environmental concerns, especially water pollution and ecosystem degradation due to the discharge of untreated or inadequately treated dye effluents. The effluents introduce various harmful chemicals altering water quality, depleting oxygen levels, harming aquatic organisms, and disrupting food chains. Dye contamination can also persist in the environment for extended periods, leading to long-term ecological damage and threatening biodiversity. Therefore, the complex effects of dye pollutants on aquatic ecosystems have been comprehensively studied. Recently, zebrafish (Danio rerio) has proved to be an effective biomedical model for this study due to its transparent embryos allowing real-time observation of developmental processes and genetic proximity (approx. 87%) to humans for studying diverse biological responses. This review highlights the various toxicological effects of industrial dyes, including cardiovascular toxicity, neurotoxicity, genotoxicity, hepatotoxicity, and developmental toxicity. These effects have been observed at different developmental stages and dye concentrations in zebrafish. The review underscores that the structure, stability and chemical composition of dyes significantly influence toxicological impact, emphasizing the need for detailed investigation into dye degradation to better understand and mitigate the environmental and health risks posed by dye pollutants.

Fabrication of innovative multifunctional dye using MXene nanosheets

The increasing demand for natural and safer alternatives to traditional hair dyes has led to the investigation of nanomaterials as potential candidates for hair coloring applications. MXene nanosheets have emerged as a promising alternative in this context due to their unique optical and electronic properties. In this study, we aimed to evaluate the potential of Ti3C2Tx (Tx = -O, -OH, -F, etc.) MXene nanosheets as a hair dye. MXene nanosheet-based dyes have been demonstrated to exhibit not only coloring capabilities but also additional properties such as antistatic properties, heat dissipation, and electromagnetic wave shielding. Additionally, surface modification of MXene using collagen reduces the surface roughness of hair and upregulates keratinocyte markers KRT5 and KRT14, demonstrating the potential for tuning its physicochemical and biological properties. This conceptual advancement highlights the potential of MXene nanosheets to go beyond simple cosmetic improvements and provide improved comfort and safety by preventing the presence of hazardous ingredients and solvents while providing versatility.

Recent Advancements in Natural Plant Colorants Used for Hair Dye Applications: A Review

There is an on-going demand in recent years for safer and "greener" hair coloring agents with the global consumer awareness of the adverse effects of synthetic hair dyes. The belief in sustainability and health benefits has focused the attention of the scientific community towards natural colorants that serve to replace their synthetic toxic counterparts. This review article encompasses the historical applications of a vast array of natural plant hair dyes and summarizes the possible coloration mechanisms (direct dyeing and mordant dyeing). Current information on phytochemicals (quinones, tannins, flavonoids, indigo, curcuminoids and carotenoids) used for hair dyeing are summarized, including their botanical sources, color chemistry and biological/toxicological activities. A particular focus is given on research into new natural hair dye sources along with eco-friendly, robust and cost-effective technologies for their processing and applications, such as the synthetic biology approach for colorant production, encapsulation techniques for stabilization and the development of inorganic nanocarriers. In addition, innovative in vitro approaches for the toxicological assessments of natural hair dye cosmetics are highlighted.

Self-Supported 3D-Printed Lattices Containing MXene/Metal-Organic Framework (MXOF) Composite as an Efficient Adsorbent for Wastewater Treatment

Metal-organic frameworks (MOFs) are well-known porous crystalline materials that have been used for the removal of organic pollutants from wastewater. To enhance the adsorption performance of these adsorbents and facilitate their recycling process, we propose a hybrid composite of an MXene/metal-organic framework (MXOF) decorated on a hierarchical and self-supported porous three-dimensional (3D) printed lattice structure (3D-MXOF). In this design, the porous MXOF composite extremely enhanced the specific surface area and synergistically promoted the dye removal efficiency of 3D-printed lattices. Scanning electron microscopy images indicated that the MXOF composite was uniformly decorated on a 3D-printed lattice structure without agglomeration. The resultant supported 3D-MXOF structures were evaluated for the adsorption of anionic dyes. The results revealed high adsorption performance (91.98% for methyl orange and 84.9% for direct red 31 dyes) and fast adsorption kinetics following a pseudo-first-order kinetic model. Moreover, the 3D-MXOF structure possesses a facile recycling process with sustainable adsorption performance after four consecutive adsorption-desorption cycles.

Advances in nanotechnology-based hair care products applied to hair shaft and hair scalp disorders

OBJECTIVE

Nanotechnology has been intensively applied to the development of novel cosmetic products for hair and scalp care during the last decades. Such a trend is corroborated by the fact that about 19% of the total nanocosmetics registered in the StatNano database are intended for hair and scalp care. Nanotechnology-enabled formulations based on nanoparticles, cyclodextrins, liposomes and nanoemulsions have emerged as novel approaches due to chemical stability and their controlled release. Regarding hair care formulations, nanocarriers can target the hair shaft, hair follicle and scalp. Therefore, they have been used to treat several hair disorders, including dandruff and other hair-damaging conditions.

METHODS

This review addressed the most important nanocarriers applied to hair-related disorders improvement. Furthermore, the application for hair photoprotection and improvement of hair colour duration by nanotechnological formulations is also approached. Besides, we provided an overview of the current scenario of available nano-based commercial hair products and novel patented inventions.

RESULTS

From the patent search, the Patent Cooperation Treaty was pointed as the most important depositing agency while the United States of America has been the most depositing country. On the contrary, according to the StatNano database, Brazil stands out in the hair care worldwide market, and it is also the main producer of hair cosmetics based on nanotechnology.

CONCLUSION

As nano-based products offer several advantages over conventional cosmetics, it is expected that in future, there will be more research on nanocarriers applied to hair disorders, as well as commercial products and patent applications.

Unravelling the role of surface modification in the dermocompatibility of silver nanoparticles in vitro and in vivo

A clearer picture of interactions between differently coated silver nanoparticles (AgNPs) and biological interfaces that are confronted with by the dermal exposure route is of utmost importance for the risk assessment of various AgNPs-based formulations utilized in the medical and dermocosmetic fields. This work sought to understand how surface modification of AgNPs, especially those produced by green synthesis strategy, affects the surface chemistry and dermocompatibility. Phytosynthetized AgNPs diverse in bio-reducing/capping agents i.e. chlorogenic acid, glycyrrhizic acid and gallic acid, were prepared by a bioinspired green approach and characterized in terms of size, shape, crystal phase, surface charge, structure and antioxidant activity. Chemically synthetized AgNPs stabilized by trisodium citrate or polyvinylpyrrolidone were also analyzed for comparison. The biological test results illustrate that varying coating material for AgNP stabilization results in differential toxicity against dermal microbes and HaCaT keratinocytes in vitro and affects dermal absorption through intact/compromised skin in vivo. Among all test samples, the citrate-stabilized AgNPs displayed the maximum cytotoxicity and dermal absorption. It is also of interest to note that the phytosynthetized AgNPs with chlorogenic acid exhibited superior antioxidant activity, attenuated cytotoxicity and minimal skin deposition, while those modified with glycyrrhizic acid demonstrated a preferentially antibacterial activity against the pathogenic (Escherichia coli and Staphylococcus aureus) over the beneficial strains (Staphylococcus epidermidis) inhabiting human skin. Furthermore, percutaneous absorption of AgNPs into live epidermis was observed on all 7-13 nm sized AgNPs, irrespective of surface coating, with more pronounced skin deposition of silver species occurring for the chemically-synthetized AgNPs within compromised skin. Given all these results, it is concluded that surface modification with particular phytochemicals may render AgNPs with enhanced dermocompatibility or antimicrobial activity. This study provides a basis for risk assessments of phytosynthetized AgNPs in consumer products and suggests the possibility of tailoring AgNPs applicability via green chemistry approach.