Tailoring the Properties of Polydiacetylene Nanosystems for Enhanced Cell Tracking Through Poly(glycerol Adipate) Blending: an In Vitro and In Vivo Investigation

This study presents novel mixed nanosystems composed of 10,12-pentacosadiynoic acid (PCDA) and biodegradable, enzymatically synthesized polymers-PGA, PGAHEX, or PGABDM - designed to alter and exploit PCDA's chromatic properties. These nanoparticles offer a cost-effective, non-leachable tracking system suitable for both in vitro and in vivo biological assays. Notably, they enable real-time monitoring without the need for additional fluorescent dyes, a common requirement in conventional systems. Fabricated via a simple nanoprecipitation method, the nanoparticles exhibit a narrow size distribution, zeta potential, and spherical morphology. Their enhanced stability in response to temperature and phosphate-buffered saline (PBS) is attributed to hydrogen bonding, hydrophobic interactions, and pi-pi stacking within the polymeric matrix. Preliminary cytotoxicity assessments using MCF-7 human breast cancer cells and the invertebrate model Caenorhabditis elegans-aligned with the 3R principle of replacing higher animals-demonstrated good biocompatibility. Importantly, both cellular and nematode uptake of PCDA and PCDA/PGA nanoparticles was successfully achieved, confirming their utility for both in vitro and in vivo tracking without the need for additional dyes.