Department of Physics, Faculty of Science, Ilam University, P.O. Box: 65315-516, Ilam, Iran.
Department of Medical Nanotechnology, School of Advanced Technologies in Medicine (SATiM), Tehran University of Medical Sciences, 14177-55469 Tehran, Iran.
Mater Sci Eng C Mater Biol Appl. 2020 Jun;111:110807. doi: 10.1016/j.msec.2020.110807. Epub 2020 Mar 3.
Tremendous demands for simultaneous imaging of biological entities, along with the drawback of photobleaching in fluorescent dyes, have encouraged scientists to apply novel and non-toxic colloidal quantum dots (QDs) in biomedical researches. Herein, a novel aqueous-phase approach for the preparation of multicomponent In-based QDs is reported. Absorption and photoluminescence emission spectra of the as-prepared QDs were tuned by alteration of QDs' composition as Zn-Ag-In-S/ZnS, Ag-In-S/ZnS and Cu-Ag-In-S/ZnS core/shell QDs. In order to reach reproducibly intense and tunable light-emissive colloidal QDs with green, amber, and red color, various optimization steps were carefully performed. The structural characterizations such as EDX, ICP-AES, XRD, TEM and FT-IR measurements were also carried out to demonstrate the success of the present method to prepare extremely quantum-confined QDs capped with functional groups. Then, to ensure their promising biomedical applications, the generated intracellular reactive oxygen species (ROS) by QDs were quantitatively and qualitatively measured in dark conditions and under 405 nm laser irradiation. Our results verified an enhancement in the generation of reactive oxygen species (ROS) and cytotoxic effects in the presence of laser irradiation while their muted toxic effects in dark conditions confirmed biocompatible properties of un-excited In-based QDs. Moreover, bioimaging analysis revealed strong merits of the suggested synthetic route to achieve ideal fluorescent QDs as bright/multi-color optical nano-probes in imaging and transporting pumps in the cell membrane. This further emphasized the potential ability of the present AgInS-based/ZnS QDs in obtaining required results as theranostic agents for simultaneous treatment and imaging of cancer. The harmonized advantages in simplicity and effectiveness of synthesis procedure, excellent structural/optical properties enriched with confirmed biomedical merits in high contrast imaging and potential treatment highlight the present work.
为了同时对生物实体进行成像，以及克服荧光染料的光漂白缺点，科学家们鼓励在生物医学研究中应用新型无毒胶体量子点（QD）。在此，报告了一种新颖的水相法制备基于 In 的多组分 QD。通过改变 QD 的组成（例如 Zn-Ag-In-S/ZnS、Ag-In-S/ZnS 和 Cu-Ag-In-S/ZnS 核/壳 QD），调整了所制备的 QD 的吸收和光致发光发射光谱。为了制备具有绿色、琥珀色和红色可调谐发光的重现性强的胶体量子点，仔细进行了各种优化步骤。还进行了 EDX、ICP-AES、XRD、TEM 和 FT-IR 测量等结构表征，以证明本方法制备具有功能基团的超量子受限 QD 的成功。然后，为了确保它们在生物医学应用中的前景，在黑暗条件和 405nm 激光照射下定量和定性地测量了 QD 产生的细胞内活性氧（ROS）。我们的结果证实，在激光照射下，活性氧（ROS）的产生和细胞毒性效应增强，而在黑暗条件下，其减弱的毒性效应证实了未激发的基于 In 的 QD 的生物相容性。此外，生物成像分析表明，该合成路线具有很强的优势，可实现理想的荧光 QD，作为细胞膜成像和转运泵中的明亮/多色光学纳米探针。这进一步强调了本研究中基于 AgInS/ZnS QD 的潜在能力，可作为癌症的同时治疗和成像的治疗剂获得所需的结果。该工作的综合优势在于合成过程的简单性和有效性、优异的结构/光学性能，以及在高对比度成像和潜在治疗方面得到证实的生物医学优势。
