24703633 OR Study of metallothionein-quantum dots interactions Dotaz Zobrazit nápovědu
Nanoparticles have gained increasing interest in medical and in vivo applications. Metallothionein (MT) is well known as a maintainer of metal ions balance in intracellular space. This is due to high affinity of this protein to any reactive species including metals and reactive oxygen species. The purpose of this study was to determine the metallothionein-quantum dots interactions that were investigated by spectral and electrochemical techniques. CuS, CdS, PbS, and CdTe quantum dots (QDs) were analysed. The highest intensity was shown for CdTe, than for CdS measured by fluorescence. These results were supported by statistical analysis and considered as significant. Further, these interactions were analysed using gel electrophoresis, where MT aggregates forming after interactions with QDs were detected. Using differential pulse voltammetry Brdicka reaction, QDs and MT were studied. This method allowed us to confirm spectral results and, moreover, to observe the changes in MT structure causing new voltammetric peaks called X and Y, which enhanced with the prolonged time of interaction up to 6 h.
Thanks to quantum dots' (QDs) properties, they can be used as selective and sensitive biomarkers in molecular imaging. In a previous paper, we confirmed the possibility of interaction between mercaptosuccinic acid-capped cadmium telluride QDs (MSA-CdTe) and human metallothionein (MT). The aim of this study was to expand on our previous research with an evaluation of the stability of the formed complexes between human MT and four CdTe compounds of the following sizes: 3.4nm (blue QDs), 3.8nm (green QDs), 4.5nm (yellow QDs), and 5.2nm (red QDs). Complexes were evaluated over time using fluorescence intensity and differential pulse voltammetry. Differences between the voltammograms obtained for standard solutions and for CdTe+MT show that complexes were formed. An increase in fluorescence intensity was observed for blue (Δ%≈40 for t=1→120min) and red (Δ%≈30 for t=1→120min) CdTe-MT complexes than CdTe alone, whereas green and yellow CdTe-MT complexes had a lower fluorescence intensity than CdTe alone. A stronger time dependence of the mercaptosuccinic acid (MSA) peak height on the timeline and differences in the MSA peak shape (in CdTe, and CdTe+MT complexes) were also observed by voltammetry. Authors noticed a decrease in the Cat2 signal of the red and green CdTe+MT complexes at the time of conjugation. Our results reveal that the size of QDs has an impact on the interaction between CdTe and human MT, as well as on the stability of complexes formed during these interactions. The bioconjugates' stability was also found to depend on the time of interaction.
- MeSH
- časové faktory MeSH
- elektrochemické techniky metody MeSH
- fluorescence MeSH
- fluorescenční spektrometrie metody MeSH
- kinetika MeSH
- kvantové tečky * MeSH
- lidé MeSH
- metalothionein chemie metabolismus MeSH
- sloučeniny kadmia chemie metabolismus MeSH
- telur chemie metabolismus MeSH
- vazba proteinů MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Peptide-peptide interactions are crucial in the living cell as they lead to the formation of the numerous types of complexes. In this study, synthetic peptides containing 11 of cysteines (α-domain of metallothionein (MT)) and sialic acid binding region (130-loop of hemagglutinin (HA)) were employed. The aim of the experiment was studying the interactions between MT and HA-derived peptides. For this purpose, fragments were tagged with cysteines at C-terminal part to serve as ligand sites for PbS and CuS quantum dots (QDs), and therefore these conjugates can be traced and quantified during wide spectrum of methods. As a platform for interaction, γ-Fe2O3 paramagnetic particles modified with tetraethyl orthosilicate and (3-aminopropyl)triethoxysilane (hydrodynamic diameter 30-40 nm) were utilized and MT/HA interactions were examined using multi-instrumental approach including electrochemistry, electrophoretic methods, and MALDI-TOF/TOF mass spectrometry. It was found that peptides enter mutual creation of complexes, which are based on some of nonbonded interactions. The higher willingness to interact was observed in MT-derived peptides toward immobilized HA. Finally, we designed and manufactured flow-through electrochemical 3D printed device (reservoir volume 150 μL) and utilized it for automated analysis of the HA/MT metal labels. Under the optimal conditions, (deposition time and flow rate 80 s and 1.6 mL/min for CuS and 120 s and 1.6 mL/min PbS, respectively), the results of peptide-conjugated QDs were comparable with atomic absorption spectrometry.