Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, Illinois61801, United States.
Mills Breast Cancer Institute, Carle Foundation Hospital, Urbana, Illinois61801, United States.
ACS Appl Mater Interfaces. 2021 Dec 22;13(50):59747-59760. doi: 10.1021/acsami.1c19995. Epub 2021 Dec 8.
We disclose for the first time a facile synthetic methodology for the preparation of multicolor carbon dots (CDs) from a single source barring any chromatographic separations. This was achieved sequential intraparticle cross-linking of surface abundant carboxylic acid groups on the CDs synthesized from a precursor to control their photoluminescence (PL) spectra as well as affect their degree of cellular internalization in cancer cells. The change in PL spectra with sequential cross-linking was projected by theoretical density functional theory (DFT) studies and validated by multiple characterization tools such as X-ray photoelectron spectroscopy (XPS), PL spectroscopy, ninhydrin assay, etc. The variation in cellular internalization of these cross-linked CDs was demonstrated using inhibitor assays, confocal microscopy, and flow cytometry. We supplemented our findings with high-resolution dark-field imaging to visualize and confirm the colocalization of these CDs into distinct intracellular compartments. Finally, to prove the surface-state controlled PL mechanisms of these cross-linked CDs, we fabricated a triple-channel sensor array for the identification of different analytes including metal ions and biologically relevant proteins.
我们首次披露了一种简便的合成方法，可从单一来源制备多色碳点（CDs），无需任何色谱分离。这是通过对从前体合成的 CDs 上表面丰富的羧酸基团进行顺序的颗粒内交联来实现的，以控制它们的光致发光（PL）光谱，并影响它们在癌细胞中的内化程度。通过理论密度泛函理论（DFT）研究预测了 PL 光谱随顺序交联的变化，并通过 X 射线光电子能谱（XPS）、PL 光谱、茚三酮测定等多种表征工具进行了验证。使用抑制剂测定、共聚焦显微镜和流式细胞术证明了这些交联 CD 的细胞内化变化。我们补充了高分辨率暗场成像，以可视化和确认这些 CD 进入不同细胞内区室的共定位。最后，为了证明这些交联 CD 的表面状态控制的 PL 机制，我们制备了一个三通道传感器阵列，用于识别不同的分析物，包括金属离子和生物相关蛋白。
