Cytotoxic and genotoxic response of an in vitro model of human fetal ventricular cardiomyocytes RL-14 in interaction with pH-dependent high molecular weight Gold-based chitosan nanoparticles

The use of chitosan in the green synthesis of metal nanoparticles influences biological recognition processes, which depend on the synthesis conditions, including pH value, temperature, and reaction time. This enables these nanostructures to be taken up at the subcellular level, causing changes in cellular biochemistry and homeostasis. The present research aimed to evaluate the cytotoxic and genotoxic effects generated in the in vitro model of human fetal ventricular cardiomyocytes (RL-14) in interaction with gold nanoparticles synthesized from high-molecular-weight chitosan (AuNPs-CsHMW). The nanoparticles were characterized by UV–Vis spectrophotometry, field-emission scanning electron microscopy, and Fourier-transform infrared spectroscopy. Additionally, the interaction between AuNPs-CsHMW and RL-14 cardiomyocytes was evaluated using trypan blue, comet assays, and mitochondrial membrane potential tests. The results showed that gold nanoparticles with colloidal stability, with apparent particle diameters between 12 nm and 30 nm, were obtained due to a pH value below the dissociation constant of chitosan. Cardiomyocytes' responses to nanoparticles were observed, with cellular viability ranging from 83% to 92%, DNA content in the head ranging from 84% to 92%, and variations in mitochondrial membrane potential. Modifying the biocompatibility response in relation to nanoparticle concentration and interaction time with the cell syncytium.