Exploring the conformational changes in fibrinogen by forming protein corona with CdTe quantum dots and the related cytotoxicity

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Molecular and biomolecular spectroscopy, 2019-09, Vol.220, p.117143, Article 117143
• Main Authors: Wang, Jing, Zheng, Xiaolin, Zhang, Hongfa
• Format: Article
• Language: English
• Subjects: CdTe quantum dots; Fibrinogen; Multi-spectroscopic studies; Nanoparticles; Protein corona
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2019.117143

This study describes synthesis of N‑acetyl‑l‑cysteine-capped CdTe quantum dots (QDs) and investigates their interaction with plasma protein fibrinogen (FIB) and the structural changes of FIB. It is shown that the interaction of QDs with FIB is a spontaneous process and the major driving forces are van der Waals forces and hydrogen bonds. Multi-spectroscopic measurements show that the intrinsic fluorescence of FIB was quenched and secondary and tertiary structures were altered due to the interaction with QDs. In addition, the aggregation state of FIB was altered in the presence of QDs. Furthermore, the formed complexes of FIB with QDs reduced the cytotoxicity of QDs. The coating of FIB on QDs could lower intracellular QDs uptake and therefore result in less released cadmium ions and ROS productions. This study, therefore, might be helpful to the comprehensive understanding of QDs toxicity and provide evidence for assessing the safe application of nanoparticles. Molecular binding model of NAC-capped CdTe QDs with fibrinogen. [Display omitted] •The interaction of FIB with QDs was studied using the fluorescence methods.•Binding interactions of FIB with QDs were systematically investigated.•Thermodynamic analysis was used to investigate the intermolecular forces.•The binding was majorly driven by van der Waals force and hydrogen-bonding interaction.•The work establishes a new strategy to evaluate combined molecular and cellular toxicity.