Georgia Tech researchers have fabricated biodegradable "STAR particles" that increased intradermal delivery of copper tripeptide-1 by up to 37-fold compared with untreated skin. The technology has already been licensed to a company preparing a 2026 clinical trial for siRNA-based eczema treatment.

The work, reported in Advanced Healthcare Materials by a team led by Mark Prausnitz, replaces earlier titania (ceramic) STARs with three polymers: water-soluble poly(vinyl alcohol) (PVA), enzyme-degradable cellulose acetate (CA), and hydrolysable polylactic acid (PLA). Each polymer suits a different drug solvent. Particles are made by femtosecond laser micromachining into star-shaped structures with sharp microneedle tips and a tapered profile.

What problem does the platform address?

"Very few drugs can be absorbed effectively into the skin, which means that many drugs in dermatology are given by mouth or injection," Prausnitz said. "This exposes the whole body to the drug, often causing side effects and reducing drug efficacy."

The stratum corneum — the skin's outermost layer — blocks most topically applied compounds, forcing clinicians toward systemic routes. Conventional microneedle patches can breach that barrier but cover only small, fixed treatment zones.

STAR particles are designed to be rubbed into the skin in a gel or cream, creating micropores across broad, irregular surfaces.

"For dermatological conditions like eczema and psoriasis, patients need to treat skin with variable and sometimes large areas," Prausnitz said. "STAR particles provide the power of a microneedle patch to increase skin permeability with the flexibility to apply them over large and variable areas by simply rubbing a gel or cream containing STAR particles on the skin."

He named eczema, psoriasis, vitiligo and allergic rashes as target indications, alongside cosmetic uses such as anti-aging and wound healing.

How large is the delivery gain on pig skin?

The team tested three drug–particle pairings on ex vivo pig skin:

• Tacrolimus + PVA in isopropyl palmitate: 1.7× intradermal drug levels after a 10-second rub; 3.2× after 30 seconds, vs. controls.
• Methotrexate + CA in water: 5.4× at 10 seconds; 25.2× at 30 seconds. Methotrexate is normally unsuited to topical delivery because of very low skin permeability.
• Copper tripeptide-1 + PLA in water: 12.1× at 10 seconds; 37× at 30 seconds.

All three particle types retained skin-puncturing performance after one week of storage, with no visible structural damage after application. Polymer STARs produced fewer pores than titania controls tested in parallel — a gap the researchers attribute to lower polymer hardness.

What changes on safety and environmental load?

The earlier titania STARs were skin-safe but not biodegradable, which raised end-of-life concerns. PVA particles dissolve on contact with wet tissue, eliminating any chance that detached microneedles could damage internal tissue.

CA and PLA particles retain structure immediately after use but become blunt and weak as enzymes or hydrolysis act on them, reducing both ingestion risk and persistent waste.

The team notes that all reported measurements are ex vivo pig-skin assays. In vivo pharmacokinetics, irritation profiles, and human dosing remain untested in the published work.

What's the commercial path?

Prausnitz told Physics World that the STAR particle technology has been licensed to a company planning a clinical trial in 2026, using STARs to deliver siRNA as a novel eczema treatment. "At Georgia Tech, we are focused on advanced materials, manufacturing and formulations for the next generation of STAR particles," he said.

That trial will determine whether ex vivo performance translates to therapeutic siRNA delivery in patients — a key milestone for R&D managers weighing the platform against patch-based or topical-encapsulation alternatives. A licensed asset, a near-term clinical date, and materials engineered to dissolve or degrade after use give portfolio teams a concrete reference point as formulation work expands toward hydrophilic drugs and larger molecules now blocked by the stratum corneum.