An NIR-Driven Upconversion/C₃N₄/CoP Photocatalyst for Efficient Hydrogen Production by Inhibiting Electron–Hole Pair Recombination for Alzheimer’s Disease Therapy

Abstract

Redox imbalance and abnormal amyloid protein (Aβ) buildup are key factors in the etiology of Alzheimer's disease (AD). As an antioxidant, the hydrogen molecule (H 2 ) has the potential to cure AD by specifically scavenging highly harmful reactive oxygen species (ROS) such as • OH. However, due to the low solubility of H 2 (1.6 ppm), the traditional H 2 administration pathway cannot easily achieve long-term and effective accumulation of H 2 in the foci. Therefore, how to achieve the continuous release of H 2 in situ is the key to improve the therapeutic effect on AD. As a corollary, we designed a rare earth ion doped g-C 3 N 4 upconversion photocatalyst, which can respond to NIR and realize the continuous production of H 2 by photocatalytic decomposition of H 2 O in biological tissue, which avoids the problem of the poor penetration of visible light. The introduction of CoP cocatalyst accelerates the separation and transfer of photogenerated electrons in g-C 3 N 4 , thus improving the photocatalytic activity of hydrogen evolution reaction. The morphology of the composite photocatalyst was shown by transmission electron microscopy, and the crystal structure was studied by X-ray diffractometry and Raman analysis. In addition, the ability of g-C 3 N 4 to chelate metal ions and the photothermal properties of CoP can inhibit Aβ and reduce the deposition of Aβ in the brain. Efficient in situ hydrogen production therapy combined with multitarget synergism solves the problem of a poor therapeutic effect of a single target. In vivo studies have shown that UCNP@CoP@g-C 3 N 4 can reduce Aβ deposition, improve memory impairment, and reduce neuroinflammation in AD mice.

Synthesis and up-to-date applications of 2D microporous g-C3N4 nanomaterials for sustainable development

“…15e). 154 Among them, g-C 3 N 4 enabled sustainable photocatalytic hydrogen production in deep tissues with the help of CoP, resulting in a substantial increase in catalytic efficiency. The multifunctional nanocomposite was confirmed to have strong anti-oxidative stress and Aβ inhibition abilities; while being able to play a role in improving memory impairment and reducing neuroinflammation in AD mice.…”

Alzheimer's Disease: Status of Low‐Dimensional Nanotherapeutic Materials

“…[116] The upconversion photocatalyst nanomaterials, UCNP@CoP@gC 3 N 4 (Table 1), improves the low solubility of H 2 (1.6 ppm) via traditional administration method and achieve the continuous release of H 2 in situ to restrain ROS in response to NIR. [117] In the subsequent discussion, we will present notable research on low-dimensional nanomaterials listed in Table 1 that exhibit dual capabilities: facile crossing of the BBB and remarkable inhibition of A𝛽, p-Tau, or ROS aggregation in AD treatment. This overview aims to offer alternative concepts and approaches for the development of multifunctional low-dimensional nanomaterials in the field of AD treatment.…”

Unraveling the role of surface and interfacial defects in hydrogen production to construct an all-in-one broken-gap photocatalyst

“…Yb 3+ /Er 3+ -based upconverting nanoparticles (UCNPs) can effectively convert low-energy near-infrared (NIR) light into high-energy ultraviolet (UV) or visible light through anti-Stokes emission. [24][25][26] Furthermore, previous studies have demonstrated that growing active photocatalysts on UCNPs can enhance their dispersion for photocatalytic reactions. 27,28 Therefore, incorporating both NIRabsorbing UCNPs and photocatalysts not only enhances overall light harvesting efficiency but also improves the dispersion of active sites in photocatalytic applications.…”