Studying the effect of different DNA concentrations on the solubility of carbon nanoparticles

Abstract

Carbon nanoparticles have attracted considerable attention in interdisciplinary nanotechnology research due to their unique physicochemical properties and broad applicability in biotechnology, biosensing, and biomedical systems. However, their limited solubility and strong tendency toward aggregation in aqueous environments remain major challenges for their effective utilization. In the present study, the effect of varying concentrations of single-stranded DNA (ssDNA) on the solubility, dispersion behavior, and colloidal stability of carbon nanoparticles was systematically investigated. Surface modification of the nanoparticles was achieved through noncovalent adsorption of ssDNA, primarily mediated by electrostatic interactions and π–π stacking between nucleobases and carbon surfaces. The resulting DNA–nanoparticle assemblies were characterized using scanning electron microscope (SEM), Zeta Potential, and fluorometric analysis. The results demonstrated that increasing DNA concentration up to an optimal range significantly enhanced nanoparticle dispersion and solubility in aqueous media, while excessively high DNA concentrations led to altered aggregation behavior. Long-term stability assessments further confirmed that DNA-functionalized nanoparticles exhibited superior temporal stability compared to unmodified samples. These findings emphasize the critical role of DNA concentration in regulating the solubility and stability of carbon nanoparticles and provide valuable insights for the rational design of stable carbon-based nanomaterials for interdisciplinary applications in nanobiotechnology and biosensing platforms.