Exploring the Effects of Various Capping Agents on Zinc Sulfide Quantum Dot Characteristics and In-vitro Fate

The In Vitro Toxicity Profile of ZnS and CdS Quantum Dots in Polysaccharide Carriers (Starch/Chitosan)

Nanocomposites are an emerging technology for ensuring food safety and quality. Their unique properties, attributed to nanoparticle presence, facilitate the development of sophisticated sensors and biosensors for detecting harmful substances, microbial growth, and environmental changes in food products. Smart and/or active food packaging development also benefits from the use of nanocomposites. This packaging, or portions of it, provide active protection for its contents and serve as sensors to promptly, simply, and safely identify any detrimental changes in stored food, without elaborate techniques or analyses. Films made from potato starch and chitosan were produced and quantum dots of zinc sulfide (ZnS) and cadmium sulfide (CdS)were synthesized in them for this study. The presence and dimensions of the QDs (quantum dots) were examined with scanning electron microscopy (SEM) and ultraviolet-visible (UV-VIS) spectroscopy. The study aimed to establish the toxicity profile of a starch-chitosan bionanocomposite integrated with ZnS and CdS quantum dots. Cytotoxic and genotoxic features were assessed through cytogenetic instability assessments, consisting of the alkaline comet assay, erythrocyte micronucleus assay, and peripheral blood cell viability analysis of a laboratory mouse model.

Exploring the Effects of Various Capping Agents on Zinc Sulfide Quantum Dot Characteristics and In-vitro Fate

The choice of capping agents used during the synthesis process of quantum dots (QDs) can significantly influence their fate and fundamental properties. Hence, choosing an appropriate capping agent is a critical step in both synthesis and biomedical application of QDs. In this research, ZnS QDs were synthesized via chemical precipitation process and three commonly employed capping agents, namely mercaptoethanol (ME), mercaptoacetic acid (MAA), and cysteamine (CA), were used to stabilize the QDs. This study was aimed to examine how these capping agents impact the physicochemical and optical characteristics of ZnS QDs, as well as their interactions with biological systems. The findings revealed that the capping agents had considerable effects on the behavior and properties of ZnS QDs. MAA-QD exhibited superior crystal lattice, smaller size, and significant quantum yield (QY). In contrast, CA-QDs demonstrated the lowest QY and the highest tendency for aggregation. ME-QDs exhibited intermediate characteristics, along with an acceptable level of cytotoxicity, rapid uptake by cells, and efficient escape from lysosomes. Consequently, it is advisable to select capping agents in accordance with the specific objectives of the research.