Toxicity in vitro and in Zebrafish Embryonic Development of Gold Nanoparticles Biosynthesized Using Cystoseira Macroalgae Extracts

Abstract

Introduction Research on gold nanoparticles (AuNPs) occupies a prominent place in the field of biomedicine nowadays, being their putative toxicity and bioactivity areas of major concern. The green synthesis of metallic nanoparticles using extracts from marine organisms allows the avoidance of hazardous production steps while maintaining features of interest, thus enabling the exploitation of their promising bioactivity. Objective To synthesize and characterize AuNPs using, for the first time, macroalga Cystoseira tamariscifolia aqueous extract (Au@CT). Methods Algal aqueous extracts were used for the synthesis of AuNPs, which were characterized using a wide panel of physicochemical techniques and biological assays. Results The characterization by UV-Vis spectroscopy, transmission electron microscopy, Z-potential and infrared spectroscopy confirmed that Au@CT were stable, spherical and polycrystalline, with a mean diameter of 7.6 ± 2.2 nm. The antioxidant capacity of the extract, prior to and after synthesis, was analyzed in vitro, showing that the high antioxidant potential was not lost during the synthesis. Subsequently, in vitro and in vivo toxicity was screened, by comparing two species of the genus Cystoseira ( C. tamariscifolia and C. baccata ) and the corresponding biosynthesized gold nanoparticles (Au@CT and Au@CB). Cytotoxicity was tested in mouse (L929) and human (BJ5ta) fibroblast cell lines. In both cases, only the highest (nominal) test concentration of both extracts (31.25 mg/mL) or Au@CB (12.5 mM) significantly affected cell viability, as measured by the MTT assay. These results were corroborated by a Fish Embryo Acute Toxicity (FET) test. Briefly, it was shown that, at the highest (nominal) tested concentration (31.25 mg/mL), CT extract induced significantly higher cytotoxicity and embryotoxicity than CB extract. However, it was demonstrated that Au@CT, but not Au@CB, were generally non-toxic. At sub-lethal (nominal) test concentrations (1.25 and 2.5 mM), Au@CT affected zebrafish embryonic development to a much lesser extent than Au@CB. In vitro wound healing assays also revealed that, while other experimental conditions did not impact cell migration, CT and Au@CT displayed a moderate positive effect. Conclusion Au@CT and Au@CB display promising features, desirable for biomedical applications, as wound healing.

Antimicrobial and anti-biofilm activity of silver nanoparticles biosynthesized with Cystoseira algae extracts

“…Thalli of live bunches of C. baccata (CB) and C. tamariscifolia (CT) were collected at the lower intertidal rocky shore in the NW coast of Spain (42º12′2.9″N; 8º47′6.2″W) and in the NW coast of Portugal (N 41 47.858′ W 008 52.423′), respectively. The algal extracts were prepared as previously reported [ 15 , 16 ].…”

“…Previously, we synthesized gold nanoparticles (AuNPs) with aqueous extracts of brown seaweeds C. baccata and C. tamariscifolia and demonstrated their good, non-cytotoxic, bioactivity towards cell regeneration and anti-tumoral properties [ 15 , 16 ]. In recent years, research on the antimicrobial potential of AuNPs has increased considerably, and findings show that these NPs trigger microbial cell damage as a result of oxidative stress, membrane and DNA damage.…”

New progress in tumor treatment based on nanoparticles combined with irreversible electroporation

“…Some studies believe that the charge on the surface of Au-NPs will cause the biological toxicity of AU-NPs. [59,[81][82][83] Among them, positively charged particles were more toxic than negative or neutral particles. [84] However, some studies believe Au-NPs are not poisonous, positively or negatively charged.…”

“…[79,80,152] The NPs have specific biological toxicity. It is not easy to control the size and shape of the particles; [59,[81][82][83] It is unevenly distributed and easy to gather, affecting the drug load and release. [70,71,73,75,153] MNPs The NPs have a particular "core-shell" structure and relatively small dosage, which can increase the sensitivity of cancer cells to radiotherapy and chemotherapy; [87,89,99] In addition, these NPs can enhance the local electric field during IRE ablation and improve the ablation range to a certain extent.…”

Evaluation of Metal‐Organic Framework MIL-89 nanoparticles toxicity on embryonic zebrafish development

“…In addition, ZF shares a high degree (~70%) of genetic similarity, functional homology, and physiological and developmental processes with humans [15] , [20] . Several studies have used ZF embryos to assess the toxicity of a wide range of nanoparticles, including iron-oxide [21] , chistosan [6] , [22] , gold [23] , silver [24] , silica [25] , as well as other subclasses of MOFs [14] , [26] .…”