Microencapsulated UV filter@ZIF-8 based sunscreens for broad spectrum UV protection

Area of Science:

• Materials Science
• Photochemistry
• Dermatology

Background:

• Sunscreens protect skin from UV damage but can degrade and cause phototoxicity.
• UV filters in sunscreens may generate harmful reactive oxygen species.

Purpose of the Study:

• To develop stable, safe, and long-lasting sunscreens using microencapsulation.
• To improve the photoprotective efficacy and reduce the toxicity of UV filters.

Main Methods:

• Microencapsulation of organic UV filters (octylmethoxycinnamate and butyl-methoxydibenzoylmethane) into zeolitic imidazole framework (ZIF-8).
• Assessment of photostability, broad-spectrum UV protection, and Sun Protection Factor (SPF) after prolonged UV exposure.
• Evaluation of UV filter release and potential for skin penetration.

Main Results:

• Encapsulated sunscreens (OMC + BMDM@ZIF-8) showed complete broad-spectrum photoprotection for 24 hours.
• ZIF-8 encapsulation stabilized UV filters, significantly reducing SPF decrease after UV exposure (e.g., 62.1 to 53.0 for OMC + BMDM@ZIF-8).
• No UV filter release was observed, and ZIF-8 particles were too large for skin penetration.

Conclusions:

• Zeolitic framework-encapsulated sunscreens offer prolonged UV protection and ultra-high SPF.
• This approach reduces UV filter degradation, phototoxicity, and skin transport.
• Microencapsulation in ZIF-8 presents a promising strategy for advanced sunscreen development.