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Advanced Neurology Graphene quantum dots approach in AD

Aβ plaques for precise imaging and potentially facilitate approaches that combine the high spatial resolution of
targeted drug delivery to these binding sites. New types of fluorescence imaging with the ability of positron emission
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QDs, such as selenium-doped QDs, show potential for AD tomography to detect radiolabeled tracers have been
treatment due to their ability to reduce oxidative stress and introduced to enhance the understanding of amyloid
prevent tau phosphorylation – the key therapeutic action pathology and disease mechanisms. These fluorescent
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in the treatment of AD. Guo et al. reported that selenium- probes, designed to target both soluble oligomers and
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doped QDs play a crucial role in scavenging free radicals, insoluble fibrils, provide a valuable tool for studying Aβ
such as hydrogen peroxide and hydroxyl radicals, thereby aggregation. However, there are possible challenges in
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reducing oxidative damage in neurons. In addition, they the photostability of certain probes and optical diffusion in
can interact with tau protein aggregates to inhibit their deep tissues, highlighting the need for further research to
formation or disassemble existing ones. Despite the address these challenges.
various advantages of QDs highlighted, there are several The assessment of neuronal activity and synaptic
challenges that need to be addressed before clinical use. function can be assessed by using newly developed imaging
One major limitation is optimizing their delivery across the techniques, such as calcium imaging and voltage-sensitive
blood–brain barrier. Future research should focus on the dye imaging. 50,85 These methods enable researchers to
potential of combining QDs with advanced technologies, monitor the individual neurons and synapses in real-time,
such as artificial intelligence-driven diagnostic platforms, thereby providing more information on neuronal circuits
to enhance precision and efficiency.
functioning in normal and pathological conditions.
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8.2. Experimental application Their significance lies in advancing the understanding
of specific mechanisms underlying neurodegenerative
The use of fluorescence imaging as a tool for detecting diseases and in developing new strategies for intervention.
amyloid plaques, which are characteristic of AD, holds great GQDs have shown great potential in biochemical assays
diagnostic potential. Through the use of fluorescent dyes for biomarker detection in AD. The unique optical
that bind specifically to amyloid proteins, neuroimaging properties, such as high fluorescence quantum yield
scientists can visualize and quantify the level of Aβ plaque and photostability, make GQDs an excellent option for
deposition in brain tissue samples. This technique sensitive and specific detection of biomolecules associated
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provides non-invasive monitoring of amyloid pathology in with AD pathology. Through the conjugation of GQDs
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pre-clinical models and potentially in human patients to with specific ligands or antibodies, biosensors that are
understand the level of disease progression and treatment capable of detecting AD biomarkers in biological samples
development. The use of fluorescence imaging with can be developed, for early diagnosis and monitoring of
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specific dyes, such as thioflavin T, and novel probes, such disease progression. Studies using in vitro and in vivo
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as temporal cortex, benzothiazole-coumarin derivative 6, models have demonstrated the efficacy of GQDs in AD
and benzothiazole-coumarin derivative 15 have significant models. In cell culture models, GQDs have been shown to
advantages in diagnosing and studying AD progression, reduce neurotoxicity, thereby suggesting a neuroprotective
based on the heterogeneity of Aβ aggregates. Recent effect. In animal models of AD, GQDs have been used
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advancements in fluorescence imaging represent a step for targeted drug delivery to the brain, improving drug
ahead in the development of more effective diagnostic tools efficacy and reducing side effects. 89
and therapeutic options for treating neurodegenerative
diseases. Moreover, innovative approaches have been In addition, GQDS have a highly versatile structure,
developed to improve the delivery of fluorescent sensors which contributes to their functions and applications.
across the blood–brain barrier, which is a critical challenge GQDs, within their graphene scaffold, have been doped
in AD diagnosis. This has been achieved by encapsulating with various heteroatoms – such as nitrogen, oxygen,
fluorescent adenosine triphosphate-reactive sensors in and fluorine – and functionalized with various chemical
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exosomes, thereby facilitating its passage through the groups. In a study conducted by Yousaf et al., they
blood–brain barrier and its accumulation in the brain. reported that fluorine-doped GQDs inhibited the human
This method has enabled real-time imaging of adenosine IAPP, offering a potential target for the treatment of AD.
triphosphate levels in AD mouse models, providing insights Several biochemical structures – such as peptides, nucleic
into disease-related energy deficits in regions, such as the acids, and polymers – can functionalize the surface of
hippocampus and cortex. This non-invasive live brain GQDs. 91-93 Several challenges are associated with achieving
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imaging technique holds great potential and implications site-specific functionalization of GQDs, which have been
for GQDs application in early diagnosis and monitoring affecting the positive progress of the development of GQDs
of AD progression. In addition, multimodal imaging and similarities in theoretical understanding. However,

Volume 4 Issue 4 (2025) 24 doi: 10.36922/an.7087