Efimova Arina A, Badrieva Zilya F, Brui Ekaterina A, Miruschenko Mikhail D, Aleinik Ivan A, Mitroshin Alexander M, Volina Olga V, Koroleva Aleksandra V, Zhizhin Evgeniy V, Liang Yingqi, Qu Songnan, Ushakova Elena V, Stepanidenko Evgeniia A, Rogach Andrey L
PhysNano Department, ITMO University, Saint Petersburg 197101, Russia.
School of Physics and Engineering, Department of Physics, ITMO University, Saint Petersburg 197101, Russia.
ACS Appl Bio Mater. 2025 Feb 17;8(2):1493-1502. doi: 10.1021/acsabm.4c01705. Epub 2025 Jan 31.
Bioimaging probes based on carbon dots (CDs) can become a useful replacement for existing commercial probes, benefiting clinical diagnostics. While the development of dual-mode CD-based probes for magnetic resonance imaging (MRI), which provides the ability for photoluminescence (PL) detection at the same time, is ongoing, several challenges have to be addressed. First, most of the CD-based probes still emit at shorter wavelengths (blue/green spectral range), which is harmful to biological objects or have very low PL intensity in the biological window of tissue transparency (red/near-infrared spectral range). Second, the relaxation characteristics of the proposed CD-based probes are still similar or only slightly larger than those of commercial contrast agents. Herein, we introduce a dual-mode probe allowing for simultaneous PL detection and MRI analysis, based on CDs doped with gadolinium ions (Gd) with a PL peak in the red (640 nm), a PL quantum yield up to 24%, and high longitudinal and transverse relaxivities reaching 25.76 and 40.57 L mmol s, respectively. Moreover, Gd-doped CDs show good biocompatibility, which was studied on H9c2 and 4T1 cell lines with a cell viability above 70%. The developed Gd-doped red-emissive CDs can be utilized as efficient and nontoxic dual-mode probes for PL and MRI measurements carried out simultaneously.
基于碳点（CDs）的生物成像探针有望成为现有商业探针的有效替代品，为临床诊断带来便利。虽然同时具备磁共振成像（MRI）和光致发光（PL）检测能力的基于CDs的双模式探针仍在研发中，但仍需解决一些挑战。首先，大多数基于CDs的探针仍在较短波长（蓝/绿光谱范围）发射，这对生物物体有害，或者在组织透明的生物窗口（红/近红外光谱范围）中PL强度非常低。其次，所提出的基于CDs的探针的弛豫特性仍与商业造影剂相似或仅略高于商业造影剂。在此，我们介绍一种双模式探针，它基于掺杂钆离子（Gd）的CDs，可同时进行PL检测和MRI分析，其PL峰值在红色（640 nm），PL量子产率高达24%，纵向和横向弛豫率分别高达25.76和40.57 L mmol s。此外，Gd掺杂的CDs具有良好的生物相容性，在H9c2和4T1细胞系上进行的研究表明细胞活力高于70%。所开发的Gd掺杂的红色发射CDs可作为高效无毒的双模式探针，用于同时进行PL和MRI测量。
