NanoBioMedical Centre, Adam Mickiewicz University, 61-614 Poznań, Poland; The Institute of Oceanology of the Polish Academy of Sciences, Powstańców Warszawy 55, 81-712 Sopot, Poland.
NanoBioMedical Centre, Adam Mickiewicz University, 61-614 Poznań, Poland.
Biomater Adv. 2025 Jan;166:214083. doi: 10.1016/j.bioadv.2024.214083. Epub 2024 Oct 22.
Cadmium-free and NIR fluorescent QDs are promising candidates for bio-application. Thus, we present the synthesis of ternary ZnCuInS/ZnS (ZCIS/ZnS) quantum dots (QDs) where the molar variation of Cu/Zn of the precursors was used to tune the optical and structural properties. QDs with Cu/Zn molar ratio of 2/1 passivated with ZnS exhibited the best optical properties. They showed dominant near-infrared photoluminescence (approx. 850 nm) and highest quantum yield (approx. 52 %, λ = 500 nm). Therefore, they were further subject to modification to ensure their transfer to the aqueous phase and improve biocompatibility. For this, different functionalization approaches were used. The first method relied on encapsulation with polymers like PSMA (poly(styrene co-maleic anhydride)) and PMAO (poly(maleic anhydride-alt-1-octadecene) coupled with polyetheramine (JEFF; Jeffamine M-1000), and the second relied on hydrophilization with PMAO. Furthermore, we also applied a surface ligand exchange process using DHLA (dihydrolipoic acid) and polyethylene glycol (PEG)-appended DHLA. The comprehensive study indicated that ZnCuInS/ZnS QDs functionalized with PMAO (ZnCuInS/ZnS@PMO) exhibited the highest photoluminescence (PL QY) along with ensured high colloidal stability in aqueous media. Moreover, no noticeable deterioration of the photoluminescence profile was observed for all used functionalization approaches. However, a significant decrease in QY was observed for almost all functionalized QDs except those that were PMO-capped. The synthesized QDs were systematically characterized by transmission electron microscopy (TEM), powder X-ray diffraction (XRD), UV-Vis absorption spectroscopy, and fluorescence spectroscopy. Biological studies indicate that the obtained hydrophilic ZCIS QDs are biocompatible and localized intracellularly inside endosomes.
无镉和近红外荧光量子点是生物应用的有前途的候选者。因此，我们提出了三元 ZnCuInS/ZnS（ZCIS/ZnS）量子点（QDs）的合成，其中前体的 Cu/Zn 摩尔变化用于调整光学和结构性质。用 ZnS 钝化的 Cu/Zn 摩尔比为 2/1 的 QDs 表现出最佳的光学性能。它们表现出主导的近红外光致发光（约 850nm）和最高的量子产率（约 52%，λ=500nm）。因此，它们进一步进行修饰以确保它们转移到水相并提高生物相容性。为此，使用了不同的功能化方法。第一种方法依赖于用聚合物如 PSMA（苯乙烯共马来酸酐）和 PMAO（马来酸酐-alt-1-十八烯）与聚醚胺（JEFF；Jeffamine M-1000）进行封装，第二种方法依赖于用 PMAO 进行亲水化。此外，我们还应用了使用 DHLA（二氢硫辛酸）和聚乙二醇（PEG）接枝的 DHLA 的表面配体交换过程。综合研究表明，用 PMAO 功能化的 ZnCuInS/ZnS QDs（ZnCuInS/ZnS@PMO）表现出最高的光致发光（PL QY），同时确保在水介质中具有高胶体稳定性。此外，对于所有使用的功能化方法，都没有观察到光致发光谱的明显恶化。然而，除了那些用 PMO 封端的 QD 之外，几乎所有功能化的 QD 的量子产率都明显下降。通过透射电子显微镜（TEM）、粉末 X 射线衍射（XRD）、紫外-可见吸收光谱和荧光光谱对合成的 QD 进行了系统表征。生物研究表明，所得的亲水性 ZCIS QD 是生物相容的，并在内涵体内部定位于细胞内。
