Pontifícia Universidade Católica

Carbonaceous nanoscale particles and hybrid materials for chemical and biomedical applications

Proponente: Professor Volodymyr Zaitsev, Ph.D., D.Sc., Corr. Membro NAS da Ucraína

Instituição: Pontifícia Universidade Católica do Rio de Janeiro, Departamento de Química

Carbon dots (CDs) is a general term that is currently used for a new class of carbonaceous nanoscale objects. CDs demonstrate photoluminescence not seen for earlier known fullerenes and nanodiamonds, can be obtained from various carbon-containing precursors in gram-scale and can produce stable suspensions in water. Unlike other photoluminescent nano-objects such as porous silicon and semiconductor quantum dots, CDs are metal-free nano-objects and thus they are much more environmentally friendly and biocompatible. Research on CDs has rapidly developed and in the last three years demonstrates high activity with more than 3000 publications/year. Recently CNDs are studied for energy storage, analytical chemistry, environmental protection, and food safety. Due to their low-toxic nature and biocompatibility CDs have great potential in biotechnology and nanomedicine, cell imaging and biolabeling, for drug release, theranostics, and photodynamic therapy. Recently we developed new procedures for the bottom-up synthesis of spherical carbonaceous nanoscale objects with sizes about 5 nm, which are commonly called carbon nanodots, CNDs (Albina Mikhraliieva, Zaitsev, Xing, et al. 2020), and other nanoparticles having much larger particle sizes (10-100 nm) with graphene basal planes and a tendency to flatten, which commonly called graphene oxide quantum dots (GOQDs). In the process of GOODs obtaining, we probably have received a new, earlier unknown 2D nanomaterial which we called Kagome graphene oxide (KGO). We managed to separate KGO from the nanoparticles. In the current project, I would like to study these novel nanoparticles and apply them for the preparation of hybrid materials. The antiviral and antibacterial activity of CND and GOQD will be studied in the project. The activity of CND and GOQD nanocomposites with metals will be studied for dynamic photo/sono therapy of cancer cells. The particles of GOQDs and KGO will be studied as vehicles in drug delivery. The hybrid materials will be obtained by covalent immobilization of nanoparticles on the surface of inorganic supports such as mesoporous silica gel and bentonite. The nanocomposites will be studied as adsorbents for the recovery of metal ions (REEs in particular) from e-waste. For this purpose carbon dots incorporated in silica gel will be functionalized with functional groups selective to ETRs, namely: 2,6-pyridinedicarboxylic acid and aminodiphosphonic acid. We have recently demonstrated that carbon nanomaterials can firmly bind to PAHs due to π-π intermolecular interactions (Albina Mikhraliieva, Gonзalves, and Zaitsev 2021). Thus we want to study the ability of new hybrids to remove PAHs from environmental objects and particularly for the extraction of polyaromatic compounds from solutions with a high lipydic content.