Han Zhenyu, Guo Allen X, Luo Taokun, Cai Tong, Mirkin Chad A
Department of Chemistry, Northwestern University, Evanston, IL 60208, USA.
International Institute for Nanotechnology, Northwestern University, Evanston, IL 60208, USA.
Sci Adv. 2025 May 9;11(19):eadv6906. doi: 10.1126/sciadv.adv6906. Epub 2025 May 7.
Proteins can template the heterogeneous nucleation and growth of size-confined nanocrystals. However, protein-templated mineralization often leads to particles that exhibit low colloidal stability, poor crystal quality, and/or diminished photoluminescence. Here, we report protein cage-spherical nucleic acids (SNAs) that can be used as nanoreactors for quantum dot (QD) synthesis and subsequent intracellular delivery. The resulting QD-SNA structures are monodisperse, colloidally stable, and photoluminescent in aqueous solution. The nanoreactors were prepared using two different proteins (~10 and 12 nanometers in diameter), and CdS, CdSe, and PbSe nanocrystals were synthesized. Moreover, the extent of surface defects and crystallinity depends on the relative concentrations of ionic precursors, which control the growth rate and the number of ionic vacancies. By optimizing conditions, CdS-SNAs that exhibit near-zero reabsorption loss were synthesized. Last, QD-SNAs exhibit enhanced cellular uptake and minimal cytotoxicity when compared to commercial QD-protein conjugates, making them potentially useful in bioimaging and diagnostic applications.
蛋白质可以为尺寸受限的纳米晶体的异质成核和生长提供模板。然而，蛋白质模板化矿化通常会导致颗粒表现出低胶体稳定性、较差的晶体质量和/或减弱的光致发光。在此，我们报道了蛋白质笼状球形核酸（SNA），其可用作量子点（QD）合成及随后细胞内递送的纳米反应器。所得的QD-SNA结构在水溶液中是单分散的、胶体稳定的且具有光致发光性。使用两种不同的蛋白质（直径约为10和12纳米）制备了纳米反应器，并合成了硫化镉（CdS）、硒化镉（CdSe）和硒化铅（PbSe）纳米晶体。此外，表面缺陷程度和结晶度取决于离子前驱体的相对浓度，这些离子前驱体控制着生长速率和离子空位的数量。通过优化条件，合成了具有近乎零重吸收损失的CdS-SNA。最后，与市售的QD-蛋白质缀合物相比，QD-SNA表现出增强的细胞摄取和最小的细胞毒性，使其在生物成像和诊断应用中具有潜在用途。
