Mechanisms facilitating the uptake of carboxyl-polythene glycol-functionalized gold nanoparticles into multicellular spheroids.

Objectives: Nanomedicines represent theragnostic alternatives to traditional candidate drugs, with increased targeting and delivery potential due to their size and functional tailorability. Biological activity typically relies on nanomaterials permeating into the intracellular environment, necessitating characterization of uptake and intracellular trafficking pathways. Spheroids' three-dimensional architecture and heterogenous cellular distribution offer an in-vivo-representative platform to assess the biological activity of nanoparticles (NPs).

Differences in uptake of 14 nm PEG-liganded gold nanoparticles into BEAS-2B cells is dependent on their functional groups.

Physico-chemical characteristics of nanoparticles have been shown to alter the uptake and toxicity of nanoparticles. This study investigated the uptake of six gold nanoparticles (AuNPs) into the human bronchial epithelial cell line BEAS-2B. The AuNPs studied included colloidal citrate-stabilised AuNPs of 14 nm in diameter; and 14 nm AuNPs conjugated to functional groups via polyethylene glycol (PEG), namely hydroxyl-PEG (POH), carboxyl-PEG (PCOOH), biotin-PEG (PBtn), nitrilotriacetic acid-PEG (PNTA), and azide-PEG (PAZ).

From the Cover: An Investigation of the Genotoxicity and Interference of Gold Nanoparticles in Commonly Used In Vitro Mutagenicity and Genotoxicity Assays.

The suitability of 4 in vitro assays, commonly used for mutagenicity and genotoxicity assessment, was investigated in relation to treatment with 14 nm citrate-stabilized gold nanoparticles (AuNPs). Specifically, the Ames test was conducted without metabolic activation, where no mutagenic effects were observed. High resolution transmission electron microscopy and Cytoviva dark-field image analysis showed that AuNPs did not enter the bacterial cells, thus confirming the unreliability of the Ames test for nanoparticle mutagenicity studies.

Cytotoxicity, intracellular localization and exocytosis of citrate capped and PEG functionalized gold nanoparticles in human hepatocyte and kidney cells.

Surface-modified gold nanoparticles (AuNPs) are nanomaterials that hold promise in drug delivery applications. In this study, the cytotoxicity, uptake, intracellular localization, and the exocytosis of citrate-stabilized (Cit-AuNP) and polyethylene glycol (PEG)-modified gold nanoparticles with the carboxyl (COOH) terminal functional group were assessed in human embryonic kidney (HEK 293) and the human caucasian hepatocytes carcinoma (Hep G2) cell systems, representing two major accumulation sites for AuNPs. The zeta (ζ)-potential measurements confirmed the negative surface charge of the AuNPs in water and in cell growth medium.

Gold nanoparticle interference study during the isolation, quantification, purity and integrity analysis of RNA.

Investigations have been conducted regarding the interference of nanoparticles (NPs) with different toxicological assay systems, but there is a lack of validation when conducting routine tests for nucleic acid isolation, quantification, integrity, and purity analyses. The interference of citrate-capped gold nanoparticles (AuNPs) was investigated herein. The AuNPs were added to either BEAS-2B bronchial human cells for 24 h, the isolated pure RNA, or added during the isolation procedure, and the resultant interaction was assessed.

Challenges facing sterilization and depyrogenation of nanoparticles: effects on structural stability and biomedical applications.

This review outlines and compares techniques that are currently available for the sterilization of nanoparticles and addresses the topic of endotoxin contamination. Several techniques are available for the removal of microbial contamination from nanoparticles developed for use in nanomedicine applications. These techniques include filtration, autoclaving and irradiation, as well as formaldehyde, ethylene oxide and gas plasma treatments.

Label-free in vitro toxicity and uptake assessment of citrate stabilised gold nanoparticles in three cell lines.

Background: Reliable in vitro toxicity testing is needed prior to the commencement of in vivo testing necessary for hazard identification and risk assessment of nanoparticles. In this study, the cytotoxicity and uptake of 14 nm and 20 nm citrate stabilised gold nanoparticles (AuNPs) in the bronchial epithelial cell line BEAS-2B, the Chinese hamster ovary cell line CHO, and the human embryonic kidney cell line HEK 293 were investigated.

Methods: Cytotoxicity of the AuNPs was assessed via traditional XTT-, LDH-, and ATP-based assays, followed by cell impedance studies.