Juliana Mărgineanu 1, 2, Ioan Matei Rusu 1, Radu Magop 1, Iarina Emma Ivanovici 1, Andreea Apădurăriței 1, Bogdan-Ionel Tamba 1 *
1 Prof. Ostin C. Mungiu Advanced Research and Development Center for Experimental Medicine – CEMEX, Grigore T. Popa University of Medicine and Pharmacy, Iasi, Romania
2 Faculty of Physics, Alexandru Ioan Cuza University of Iasi, Iasi, Romania
* Correspondence to: Bogdan-Ionel Tamba, Prof. Ostin C. Mungiu Advanced Research and Development Center for Experimental Medicine – CEMEX, Grigore T. Popa University of Medicine and Pharmacy, Iasi, Romania. E-mail: bogdan.tamba@umfiasi.ro
Abstract
Alzheimer’s Disease (AD) represents a global health crisis characterized by complex multifactorial etiology and severe pharmacological limitations imposed by the Blood–Brain Barrier (BBB). This narrative review critically synthesizes recent advancements (2021–2026) regarding the application of Carbon Quantum Dots (CQDs) as a transformative nanotechnological paradigm for AD management. Unlike traditional semiconductor quantum dots, CQDs synthesized via eco-friendly “green” protocols offer superior biocompatibility and unique physicochemical properties ideal for central nervous system interfacing. The article details the molecular mechanisms—specifically passive diffusion and carrier-mediated transport, alongside alternative intranasal and intrathecal routes—that enable surface-engineered CQDs to bypass or circumvent the BBB. A dual-functional analysis high lights the versatility of these structures: diagnostically, they facilitate ultra-sensitive pre symptomatic detection of amyloid-beta and Tau biomarkers through Near-Infrared (NIR) bioimaging and fluorescent biosensing; therapeutically, CQDs are presented as multi-target agents that exhibit intrinsic neuroprotective capabilities (inhibiting protein aggregation and scavenging Reactive Oxygen Species) while serving as advanced vectors for the targeted delivery of genetic materials and neurotrophic drugs such as memantine and insulin. Central to this review is the concept of personalized medicine, exploring “theranostic” platforms and stimuli-responsive smart delivery systems (e.g., pH-sensitive) that adapt to the individual pathological microenvironment. The review concludes by addressing critical challenges regarding long-term biosafety, “protein corona” formation, and manufacturing scalability, while outlining future perspectives focused on autophagy reactivation and the standardization required for clinical translation.