Negatively charged gold nanoparticles as a dexamethasone carrier: stability in biological media and bioactivity assessment in vitro

Abstract

Gold nanoparticles (AuNPs) have been extensively used in biological applications because of their high\ud biocompatibility, ease of characterization and the extensive knowledge of their surface chemistry. These\ud features make AuNPs readily exploitable for drug delivery and novel diagnostic and therapeutic\ud approaches. In a previous work, we showed that small size (5–10 nm) AuNPs functionalized by sodium\ud 3-mercapto-1-propanesulfonate (3MPS) can be efficiently loaded with the glucocorticoid drug\ud dexamethasone (DXM) and are stable in water and PBS. In the present study, we further analysed the\ud stability and the drug release kinetics of DXM-loaded AuNPs functionalized by sodium 3mercaptopropane\ud sulfonate (AuNP-3MPS/DXM) and their unconjugated counterparts (AuNP-3MPS) in\ud different biological media. Moreover, we evaluated AuNP-3MPS cyto-compatibility on two mammalian\ud cell lines and tested their specific activity as drug carriers on DXM-sensitive murine and human tumor\ud cells. The colloidal stability of AuNP-3MPS/DXM was significantly increased in all tested culture media,\ud compared with the unconjugated AuNP-3MPS and both AuNP-3MPS formulations which proved nontoxic\ud to biological systems in vitro. Most importantly, we showed that AuNP-3MPS/DXM continuously\ud release bioactive DXM molecules that efficiently induce cell proliferation arrest and apoptotic cell death\ud on a human lymphoma cell line and upregulation of the DXM-inducible programmed cell death-1 (PD-1)\ud molecule on activated mouse T lymphocytes. These data confirm that the AuNP-3MPS/DXM conjugate\ud is a promising system for drug delivery and open interesting perspectives for future in vivo applications

Inkjet Printed Nanopatterned Aptamer‐Based Sensors for Improved Optical Detection of Foodborne Pathogens

“…In line with the UV–vis results, the ζ potential presented significant changes providing confirmation of each assembled layer (Figure c). The bare polystyrene particles showed a negative relative surface charge of −33.3 ± 6.41 mV which relates with the anionic nature of the initiator during the chain‐growth polymetization, when gold was reduced on the core material surface the apparent negative ζ potential slightly increased to –43.1 ± 10.6 mV, due to the presence of negative citrate ions stabilizing the particles; Finally, the apparent ζ potetinal became positive (+33.4 ± 5.82 mV) in presence of a layer rich in amine groups provided by the B‐PEI grafting …”

Gold Nanoparticles and Nanorods in Nuclear Medicine: A Mini Review

“…AuNPs can be synthesized by means of several processes such as chemical, physical, and biological methods [24,[49][50][51]65]. A well-known bottom-up approach is a wet reduction in the presence of a capping agent [55,57,[59][60][61][62]64]. The obtained AuNPs can be easily investigated by microscope techniques, such as transmission electron microscope (TEM), scanning electron microscope (SEM), and atomic force microscope (AFM) [98][99][100][101][102].…”

“…In particular, the attachment of radionuclides could influence the surface properties and modify the capability of loading other targeting or therapeutic compounds. In the U87MG glioma cell line, the targeting capability of the arginine-glycine-aspartic acid (RGD) peptide after 64 Cu integration in AuNRs was assessed. The RGD maintains its capability of targeting integrin after 64 Cu treatment [41].…”

“…In the U87MG glioma cell line, the targeting capability of the arginine-glycine-aspartic acid (RGD) peptide after 64 Cu integration in AuNRs was assessed. The RGD maintains its capability of targeting integrin after 64 Cu treatment [41]. Similarly, the attachment of PEG-trastuzumab (HER2-specific monoclonal antibody molecules) on the AuNPs surface (Ø = 5 nm) does not change the 211 At absorption [82].…”

“…In fact, they show remarkable chemical-physical properties, such as an easy modifiable morphology/size/surface, modulable optical absorption and scattering, photothermal and photoacoustic enhancements, and a wide surface/volume ratio that is suitable for interaction with the environment [50][51][52][53]. The gold surface can be functionalized and linked with drugs [54-57] and biomolecules, such as enzymes, antibodies, DNA, and peptides to achieve a specific site [58][59][60][61][62][63][64][65][66], and they are also studied to develop innovative antibacterial systems [67][68][69][70].In the wide field of advanced materials that represent the frontier where gold-based materials and nuclear medicine meet, this review provides an updated scenario of the progress in this young research field, focusing on gold nanoparticles (AuNPs) and nanorods (AuNRs) used in diagnosis and therapy, as schematized in Figure 1. The first key topic is the chemical preparation of gold-based nanomaterials, which is focused on spheres and rods.…”