# Photochemical transformations of multicomponent aggregates containing photolabile small molecules, heavy metal ions, and/or nanoparticles in biological environments

> **NIH NIH R15** · STATE UNIVERSITY OF NY,BINGHAMTON · 2020 · $450,480

## Abstract

Abstract
Every day, light transforms hundreds of millions of tattoos. Despite the fact that laser tattoo removal is
a multi-billion dollar per year industry, we understand surprisingly little about tattoo photodegradation,
the hazards of the photoproducts, and the subsequent health risks to people with tattoos. Tattoo inks
themselves may contain high levels of toxic heavy metals, cytotoxic nanomaterials, and potentially
carcinogenic molecular pigments. What is specifically unclear is how photodegradation transforms
and/or releases harmful materials into the body. Of the handful of studies that purport to investigate
tattoo photochemistry, most have little biological relevance (e.g., studies conducted in deoxygenated
organic solvents), explore materials not used in tattoos, or simply do not even consider tattoos at all.
Understanding tattoo photodegradation and the attendant risks requires a strategy that couples
analytical chemistry and photochemistry with materials physics and cellular biology. This proposal
details a transdisciplinary approach designed around meaningful, authentic research experiences for
undergraduate students. We plan to pursue three complementary, yet distinct, specific aims. 1)
Students will use analytical methods to identify the photodecomposition products of tattoo inks. Under
illumination, molecular pigments can breakdown into carcinogenic products (benzene, primary
amines, halogenated aromatics) though the identities of these products are often unknown. Also
unexplored is the impact of semiconductor particles usually present in inks. 2) Using a combination of
time-resolved spectroscopies, students will explore how embedded tattoo inks break down under
illumination. We understand little about how light causes tattoo inks to leave the dermal layer and, in
fact, the assumed mechanism of particle fragmentation has never actually been demonstrated
experimentally. We will directly observe tattoo inks undergoing laser-illumination using nanosecond
shadowgraphy and couple that with photoacoustic spectroscopy and luminescent thermometry to
understand what conditions the ink particles experience under illumination and when they start to
fragment. 3) We will use human dermal fibroblasts as a model for the human dermis to understand
the potential effects of tattoos inks and photodecomposition products on cell viability. Students will
assess the potential toxicity of the tattoo inks themselves, as well as the photoproducts, through a
variety of assays to build a detailed picture of the cytotoxicity of photodegraded tattoos. Successful
completion of this project will yield a significantly deeper understanding of the risks faced by millions
of Americans with tattoos as well as offer a unique and meaningful training experience for
undergraduate students.

## Key facts

- **NIH application ID:** 10114690
- **Project number:** 1R15GM140404-01
- **Recipient organization:** STATE UNIVERSITY OF NY,BINGHAMTON
- **Principal Investigator:** John Swierk
- **Activity code:** R15 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $450,480
- **Award type:** 1
- **Project period:** 2020-09-15 → 2024-08-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10114690

## Citation

> US National Institutes of Health, RePORTER application 10114690, Photochemical transformations of multicomponent aggregates containing photolabile small molecules, heavy metal ions, and/or nanoparticles in biological environments (1R15GM140404-01). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10114690. Licensed CC0.

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