*6.4. Quantum Dots*

Quantum dots are fluorophores constituted by clusters of atoms at the nanometric scale containing a few hundred to a few thousand atoms of a semiconductor material wrapped by an additional semiconductor layer to improve the optical properties of the material (Figure 3). Quantum dots have been successfully used in immunocyto- and histochemistry, in flow cytometry, and in confocal microscopy [106,107].

Amino(polyethylene glycol)-2000 molybdenum disulfide quantum dots conjugated to (3-carboxypropyl)triphenyl-phosphonium bromide (TPP-MoS2 QDs) have been fabricated and tested in mouse models of AD [108]. These TPP-MoS2 QDs have the ability to cross the BBB and target mitochondria with TPP. These TPP-MoS2 QDs are able to induce a change in the phenotype of the microglia from pro-inflammatory M1 to anti-inflammatory M2 [108]. This contributes to the removal of Aβ aggregates [108].

#### **7. Conclusions**

DHA has shown cytoprotective effects on microglial cells but also on microglia activation in vitro and in vivo in animal models. In clinical studies, positive effects on the development of neurodegenerative diseases have been observed, but some conclusions are divergent and require further investigation, since DHA has a systemic and not a targeted release at the brain level. This may lead to the use of nanoparticles that could allow a release at the brain level of DHA and improve its effectiveness at the level of the microglia, thus leading to better management of neurodegenerative diseases associated with neuroinflammation.

**Author Contributions:** Conceptualization, A.V.; Supervision, A.V.; writing and editing, K.C., G.L., and A.V.; proofreading, I.G. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Acknowledgments:** This work was supported by the University of Bourgogne (Dijon, France).

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **References**


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