Heather Clark isn’t your average tattoo artist. She won’t take requests, and her tat­toos won’t be per­ma­nent. They won’t even make people look hip — but they will keep them healthier.

Clark, an asso­ciate pro­fessor of phar­ma­ceu­tical sci­ences in North­eastern University’s Bouvé Col­lege of Health Sci­ences, is devel­oping tat­toos that involve nanosen­sors injected into an upper layer of the skin—a far less inva­sive, and thus less painful, process than a tra­di­tional tattoo.

She tar­geted this inno­v­a­tive approach to help dia­betic patients con­tin­u­ously mon­itor glu­cose levels. The problem for many dia­betics, she said, is they must mea­sure their blood-​​sugar levels by pricking a finger sev­eral times a day—an ago­nizing, repet­i­tive process that Clark said becomes more dif­fi­cult when patients are trav­eling or trying to find a clean, pri­vate environment.

They are tired of having to take time out of their lives to do this,” said Clark, noting calls she’s received from par­ents who say they stay up with their dia­betic chil­dren every night because they are wor­ried about a hypo­glycemic event.

Now, she has pub­lished a paper in the journal Inte­gra­tive Biology that applies the same con­cept to mon­i­toring sodium levels, which she said can be useful to check kidney func­tion during prostate surgery, and even to track long-​​distance run­ners’ hydra­tion levels. Clark col­lab­o­rated with North­eastern bio­engi­neering grad­uate stu­dent Matt Dubach on the paper, which they coau­thored with col­leagues in Cal­i­fornia at the high-​​tech firm Caliper Life Sciences.

The project, which aligns with Northeastern’s com­mit­ment to research that solves global chal­lenges in health, secu­rity and sus­tain­ability, aims to dra­mat­i­cally improve how cer­tain health con­di­tions are mon­i­tored and treated.

Clark said patients would reapply the tat­toos about once a week. The process would involve injecting small beads con­taining flu­o­res­cent par­ti­cles into the epi­dermal layer of the skin; the flu­o­res­cent glow would become more intense — and even change color — as glu­cose or sodium levels drop. Clark said that ide­ally, the levels would be mon­i­tored with a hand­held elec­tronic device.

Clark’s research pri­marily focuses on devel­oping nanosen­sors, and the tattoo con­cept evolved out of her intra­cel­lular work at Draper Lab­o­ra­to­ries. She will con­tinue col­lab­o­rating closely with Draper researchers while at Northeastern.

Tattoo artists basi­cally poke holes and inject ink, which is made of par­ti­cles, into the skin, where they reside for the rest of your life. Our sen­sors are nanopar­ti­cles, so it seemed like a nat­ural choice to use these as a tattoo for mon­i­toring health status,” she said.

View selected pub­li­ca­tions of Heather Clark in IRis, Northeastern’s dig­ital archive.