By Ana Espino | Published on July 21, 2025 | 2 min read
#Photoprotection #Sunscreen #Nanomaterials
#Polymers #SPF
Photoprotection is a fundamental pillar in the
prevention of skin disorders caused by ultraviolet (UV) exposure. As the
incidence of melanoma and carcinoma continues to rise, the actual efficacy of
sunscreens is becoming a public health issue. While current organic and mineral
UV filters offer theoretically effective protection, their performance largely
depends on the
quality of the film formed on the skin’s surface. In real-world
conditions, factors like
uneven distribution, filter crystallization, solvent
evaporation, and
mechanical friction disrupt film cohesion and compromise the
labeled SPF value. Increasing the concentration of UV filters to compensate for
these losses faces several obstacles: irritation risks, poor cosmetic
tolerance, and environmental impact.
In response to these limitations,
new
formulation approaches are emerging, focusing on the structure and stability of
the protective film rather than solely on filter concentration. This review
examines recent advances in using hydrocarbon-based
film-forming agents and
carbon-based nanomaterials to
improve sunscreen adherence, durability, and
photostability.
A stronger film, a higher SPF?
This study analyzes recent sunscreen
formulations incorporating
hydrophobic film-forming polymers and
carbon-based
nanomaterials such as fullerenes and nanodiamonds.
These components enhance UV
filter distribution, reduce crystallization, and create a more uniform and
resilient barrier on the skin. Water-in-oil (W/O) systems, which are more
lipophilic, also provide better skin adherence compared to traditional
oil-in-water (O/W) emulsions.
The results confirm that formulations enriched
with hydrocarbon film-forming agents and carbon nanomaterials significantly
improve the
overall photostability of sunscreens. These formulations better
withstand environmental stress while maintaining effective protection over
extended periods. One key benefit lies in the
antioxidant properties of
nanomaterials like fullerenes, which not only
absorb UV radiation but also
neutralize free radicals generated by sun exposure. This dual action helps
limit oxidative damage to cell membranes and skin collagen, while prolonging
the active lifespan of embedded UV filters.
Additionally, the study shows that these
formulations
enhance interfacial cohesion, promote
more uniform UV filter
distribution, and
improve resistance to water, sweat, and mechanical abrasion.
These findings confirm the value of these novel components in optimizing
sunscreen performance under real-world use conditions.
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Towards smarter, more stable sunscreens
UV-related skin cancers and photoaging remain
major challenges in preventive dermatology. Given the partial ineffectiveness
of conventional sunscreens in actual use, the current challenges lie in
improving the
stability, skin adherence, and tolerance of sun protection
without increasing UV filter content.
This review aimed to explore how incorporating
hydrocarbon film-formers and carbon-based nanomaterials can boost the overall
performance of sunscreens—particularly their ability to form homogeneous,
stable, and photoprotective films on the skin’s surface. The results show that
these innovative components significantly enhance the photostability, cohesion,
and resilience of sunscreen films, while providing
additional antioxidant
benefits. Photoprotective efficacy thus depends not just on UV filter concentration,
but on the structural quality of the applied film.
Future directions include the development of
biocompatible formulations with these smart agents, the standardization of
testing protocols on human skin, and in-depth assessments of the safety and
environmental impact of nanomaterials. These advances may pave the way for a
new generation of sunscreens that are safer, more effective, and better suited
to current demands in skin health and sustainability.
Read next: CBD & Sun: innovation beneath the skin
About the author – Ana EspinoPhD in Immunology, specialized in Virology
