There are various concerns with current sunscreen actives in the sun care industry which pushes for a natural-based active that is sustainable as well as effective. Lignin is a natural polymer, capable of ultraviolet (UV) filtration and maintaining photostability. In this study, a variety of tuneable lignin-poly(ethylene glycol) (LP) nanodiamond (LP–ND) complexes were developed with varying ratios of LP to NDs. There are two fractions of LP–NDs, which use detonation NDs (LP–rNDs) and furnace NDs (LP–mNDs). Both complexes demonstrated favorable UV filtration, enhanced photostability, and uniform dispersion in water and cream. The LP–mND had maintained its particle size at <200 nm with an increasing LP ratio from 0.5 to 20 times as opposed to the increased particle size of the LP–rND. The LP–mND complex excelled in its photostability during solar radiation from 1 h to 6 h, demonstrating its effectiveness in absorbing 70% in the UV B region. Results had indicated enhanced synergistic effect of LP–rNDs and LP–mNDs with commercial sunscreen. The LP–rND complex had enhanced the sunscreen from 29 to 62, whereas the LP–mND had further boosted the sun protection factor to 89. In a nutshell, the lignin nanodiamond complexes offer a sustainable alternative to current actives in the industry.

防晒行业目前的防晒活性成分存在各种问题，这推动了一种可持续且有效的天然活性成分。木质素是一种天然聚合物，能够过滤紫外线 (UV) 并保持光稳定性。在这项研究中，开发了各种可调节的木质素-聚（乙二醇）（LP）纳米金刚石（LP-ND）复合物，其 LP 与 ND 的比例不同。LP-NDs 有两个部分，它们使用爆轰 NDs (LP-rNDs) 和熔炉 NDs (LP-mNDs)。两种复合物均表现出良好的紫外线过滤效果、增强的光稳定性以及在水和乳霜中的均匀分散。LP-mND 的粒径保持在 <200 nm，LP 比率从 0.5 倍增加到 20 倍，这与 LP-rND 的粒径增加相反。LP-mND 复合物在 1 至 6 小时的太阳辐射期间具有出色的光稳定性，证明其在 UV B 区域吸收 70% 的有效性。结果表明 LP-rNDs 和 LP-mNDs 与商业防晒剂的协同作用增强。LP-rND 复合物将防晒系数从 29 提高到 62，而 LP-mND 进一步将防晒系数提高到 89。简而言之，木质素纳米金刚石复合物为行业中当前的活性物质提供了可持续的替代品。