Direct Conjugation of Resveratrol on Hydrophilic Gold Nanoparticles: Structural and Cytotoxic Studies for Biomedical Applications

Abstract

Strongly hydrophilic gold nanoparticles (AuNPs), functionalized with citrate and L-cysteine, were synthetized and used as Resveratrol (RSV) vehicle to improve its bioavailability. Two different conjugation procedures were investigated: the first by adding RSV during AuNPs synthesis (1) and the second by adding RSV after AuNPs synthesis (2). The two different conjugated systems, namely AuNPs@RSV1 and AuNPs@RSV2 respectively, showed good loading efficiency (η%): η1 = 80 ± 5% for AuNPs@RSV1 and η2 = 20 ± 3% for AuNPs@RSV2. Both conjugated systems were investigated by means of Dynamic Light Scattering (DLS), confirming hydrophilic behavior and nanodimension (<2RH> 1 = 45 ± 12 nm and <2RH> 2 = 170 ± 30 nm). Fourier Transform Infrared Spectroscopy (FT-IR), Synchrotron Radiation induced X-Ray Photoelectron Spectroscopy (SR-XPS) and Near Edge X-ray Absorption Fine Structure (NEXAFS) techniques were applied to deeply understand the hooking mode of RSV on AuNPs surface in the two differently conjugated systems. Moreover, the biocompatibility of AuNPs and AuNPs@RSV1 was evaluated in the concentration range 1.0–45.5 µg/mL by assessing their effect on breast cancer cell vitality. The obtained data confirmed that, at the concentration used, AuNPs do not induce cell death, whereas AuNPs@RSV1 maintains the same anticancer effects as the unconjugated RSV.

Role of Resveratrol in Prevention and Control of Cardiovascular Disorders and Cardiovascular Complications Related to COVID-19 Disease: Mode of Action and Approaches Explored to Increase Its Bioavailability

“…Gold nanoparticles (AuNPs) are of particular interest in biomedical application due to their physicochemical features such as controllable shape and size, as well as the potential for surface functionalization with bioactive agents [ 97 ]. Resveratrol conjugated to highly hydrophilic gold nanoparticles (AuNPs), previously functionalized with citrate and L-cysteine, maintains the biological activity of the unconjugated resveratrol [ 98 ] similar to gold nanoparticles conjugated with resveratrol via polyvinylpyrrolidone (PVP) as cross-linker [ 99 ] and gum arabic-stabilized resveratrol-encapsulated gold nanoparticles [ 100 ].…”

“…An important aspect to consider is the concentration of resveratrol used in in vitro experiments that is often 10–100 times greater than the one observed in human plasma after oral consumption [ 220 ]. In addition to shortcomings related to inherent biological limitations of resveratrol, gut microbiota and genetic background account for inter-individual responses to orally administered resveratrol [ 98 ]. Given the non-physiological concentrations used in in vitro studies and omission of the contribution of resveratrol metabolites to measured effects, translation of results obtained in in vitro experiments to those obtained in clinical trials is somewhat difficult.…”

Role of Resveratrol in Prevention and Control of Cardiovascular Disorders and Cardiovascular Complications Related to Covid-19 Disease: Mode of Action and Approaches Explored to Increase Its Bioavailability

“…An important aspect to consider is the concentration of resveratrol used in in vitro experiments that is often 10-100 times greater than the one observed in human plasma after oral consumption [215]. In addition to shortcomings related to inherent biological limitations of resveratrol, gut microbiota and genetic background account for inter-individual responses to orally administered resveratrol [98]. Given the non-physiological concentrations used in in vitro studies and omission of the contribution of resveratrol metabolites to measured effects, translation of results obtained in in vitro experiments to those obtained in clinical trials is somewhat difficult.…”

Radiation dose enhancement using gold nanoparticles with a diamond linear accelerator target: a multiple cell type analysis

“…Increasing the probability for X-ray interactions is essential to the efficacy of the DTB to induce damage in tumors, and was recently illustrated in a gadolinium nanoparticle-based study using a filter-free LINAC beam 6 , 10 . Emerging research on NPs illustrates surface functionalization of GNPs to have advantages for biomedical applications such as nuclear imaging, radiometabolic therapy 14 – 16 and targeted delivery of compounds like chemotherapeutic drugs to further radiosensitize cancer cells 7 .…”