Araújo Catarina, Rodrigues Raquel O, Bañobre-López Manuel, Silva Adrián M T, Ribeiro Rui S
LSRE-LCM - Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
Pharmaceutics. 2025 Apr 6;17(4):477. doi: 10.3390/pharmaceutics17040477.
: The development of effective therapies for brain disorders is highly correlated with the ability of drugs or nanosystems to cross the blood-brain barrier (BBB), which has been limited. Recently, carbon dots (CDs) have been receiving attention to be used as BBB-crossing theranostic agents due to their inherent advantages, such as low size, excellent biocompatibility, high quantum yield (QY), tunable fluorescence, high drug loading, and relatively easy synthesis at low cost. The aim of this study was to design CDs with precisely controlled fluorescence properties for advanced bioimaging and an in-depth assessment of BBB permeability. : CDs were synthesized using a microwave-assisted approach, optimized through microwaves' irradiation time, and employing citric acid, urea, and sodium fluoride as precursors. The optimized sample was labeled as NF-CD. : A comprehensive physicochemical, photoluminescence, and biological characterization revealed the ability of NF-CD to diffuse across a neuromimetic-BBB model, mainly due to their small size (average diameter of 4.0 ± 1.1 nm), exhibiting excitation-dependent fluorescence in the blue and green wavelengths, high biocompatibility and QY, and exceptional photostability. : Owing to the exceptional fluorescence characteristics and biological compatibility, NF-CD presents promising opportunities in theranostic applications, particularly in brain-targeted bioimaging, nanocarrier-based drug and immunotherapy delivery, early-stage diagnostics, and personalized medicine. NF-CD's ability to cross the BBB further underscores the relevance of pioneering nanomaterial-based strategies for neurological disorder diagnostics and precision-targeted therapeutic interventions. Overall, this research contributes to the broader field of nanotechnology-driven biomedical advancements, fostering innovations in neurological diagnostics and therapeutic delivery systems.
用于脑部疾病的有效治疗方法的发展与药物或纳米系统穿越血脑屏障（BBB）的能力高度相关，而这一能力一直受到限制。最近，碳点（CDs）因其固有的优势，如尺寸小、生物相容性优异、量子产率（QY）高、荧光可调、药物负载量大以及相对容易以低成本合成，而受到关注，有望用作穿越血脑屏障的诊疗试剂。本研究的目的是设计具有精确可控荧光特性的碳点，用于先进的生物成像以及对血脑屏障通透性的深入评估。通过微波辅助方法合成碳点，通过微波辐照时间进行优化，并使用柠檬酸、尿素和氟化钠作为前驱体。优化后的样品标记为NF-CD。全面的物理化学、光致发光和生物学表征揭示了NF-CD能够扩散穿过神经仿生血脑屏障模型，这主要归因于其小尺寸（平均直径为4.0±1.1纳米），在蓝色和绿色波长下表现出激发依赖性荧光，具有高生物相容性和量子产率，以及出色的光稳定性。由于其卓越的荧光特性和生物相容性，NF-CD在诊疗应用中展现出广阔的前景，特别是在脑靶向生物成像、基于纳米载体的药物和免疫治疗递送、早期诊断以及个性化医疗方面。NF-CD穿越血脑屏障的能力进一步强调了基于纳米材料的开创性策略在神经系统疾病诊断和精准靶向治疗干预中的相关性。总体而言，本研究为纳米技术驱动的生物医学进步这一更广泛领域做出了贡献，促进了神经诊断和治疗递送系统的创新。
