A scoping review of methodologies opted for photoprotection of herbal formulation for the herbal sunscreen formulation

Abstract

In the current scenario, fragmented and inconsistent photoprotective evaluation methodologies for herbal drugs and formulations must be evaluated and standardised through a scoping review. In order to identify gaps, improve scientific rigour, and support the development of potent herbal photoprotective agents, this review methodically examines the current landscape of experimental approaches and analytical techniques used to evaluate herbal and Ayurvedic sunscreen formulations. Peer-reviewed studies published since 2000 were included, and a review was carried out in accordance with PRISMA-ScR guidelines, and databases like PubMed, Science Direct, AYUSH Research Portal, and Google Scholar were searched. Studies that used analytical standardisation techniques like UV-Vis spectrophotometry, FTIR, or HPLC and examined herbal or plant-based formulations for photoprotective efficacy using in-vitro, ex-vivo, in-vivo, or clinical models were included. Of the 1445 Studies, 36 studies-28 in vitro, 7 in vivo, and 1 clinical trial met the eligibility criteria of the review. The findings show that phytochemicals such as flavonoids, polyphenols, and carotenoids are widely used and a variety of dosage forms, such as creams, gels, nanoemulsions, and liposomes, were formulated. These formulations showed cellular protection, antioxidant capacity, and quantifiable SPF values. Nonetheless, there is a wide variation in formulation strategies, assessment criteria, and standardisation methods. In order to promote the development and clinical translation of sunscreens derived from plants, the review highlights the urgent need for standardised protocols and regulatory alignment. This work provides a consolidated foundation for future research and innovation in natural or Herbal photoprotection.