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Background: The hippocampus is associated with mood disorders, and the activation of quiescent neurogenesis has been linked to anxiolytic effects. Near-infrared (NIR) light has shown potential to improve learning and memory in human and animal models. Despite the vast amount of information regarding the effect of visible light, there is a significant gap in our understanding regarding the response of neural stem cells (NSCs) to NIR stimulation, particularly in anxiety-like behavior. The present study aimed to develop a new optical manipulation approach to stimulate hippocampal neurogenesis and understand the mechanisms underlying its anxiolytic effects. Methods: We used 940 nm NIR (40 Hz) light exposure to stimulate hippocampal stem cells in C57BL/6 mice. The enhanced proliferation and astrocyte differentiation of NIR-treated NSCs were assessed using 5-ethynyl-2'-deoxyuridine (EdU) incorporation and immunofluorescence assays. Additionally, we evaluated calcium activity of NIR light-treated astrocytes using GCaMP6f recording through fluorescence fiber photometry. The effects of NIR illumination of the hippocampus on anxiety-like behaviors were evaluated using elevated plus maze and open-field test. Results: NIR light effectively promoted NSC proliferation and astrocyte differentiation via the OPN4 photoreceptor. Furthermore, NIR stimulation significantly enhanced neurogenesis and calcium-dependent astrocytic activity. Moreover, activating hippocampal astrocytes with 40-Hz NIR light substantially improved anxiety-like behaviors in mice. Conclusions: We found that flickering NIR (940 nm/40Hz) light illumination improved neurogenesis in the hippocampus with anxiolytic effects. This innovative approach holds promise as a novel preventive treatment for depression. [ABSTRACT FROM AUTHOR]

Peripheral nerve repair remains a major clinical challenge, particularly in the pursuit of therapeutic approaches that ensure adequate recovery of patient's activity of daily living. Autografts are the gold standard in clinical practice for restoring lost sensorimotor functions nowadays. However, autografts have notable drawbacks, including dimensional mismatches and the need to sacrifice one function to restore another. Engineered nerve guidance conduits have therefore emerged as promising alternatives. While these conduits show surgical potential, their clinical use is currently limited to the repair of minor injuries, as their ability to reinnervate limiting gap lesions is still unsatisfactory. Therefore, improving patient functional recovery requires a deeper understanding of the cellular mechanisms involved in peripheral nerve regeneration and the development of therapeutic strategies that can precisely modulate these processes. Interest has grown in the use of external energy sources, such as light, ultrasound, electrical, and magnetic fields, to activate cellular pathways related to proliferation, differentiation, and migration. Recent research has explored combining these energy sources with tailored nanostructured materials as nanotransducers to enhance selectivity towards the target cells. This review aims to present the recent findings on this innovative strategy, discussing its potential to support nerve regeneration and its viability as an alternative to autologous transplantation. [ABSTRACT FROM AUTHOR]

Near‐infrared photosensitizers are valuable tools to improve treatment depth in photodynamic therapy (PDT). However, their low singlet oxygen (1O2) generation ability, indicated by low 1O2 quantum yield, presents a formidable challenge for PDT. To overcome this challenge, the heptamethine cyanine was decorated with biocompatible S (Scy7) and Se (Secy7) atom. We observe that Secy7 exhibits a redshift in the main absorption to ~840 nm and an ultra‐efficient 1O2 generation capacity. The emergence of a strong intramolecular charge transfer effect between the Se atom and polymethine chain considerably narrows the energy gap (0.51 eV), and the heavy atom effect of Se strengthens spin–orbit coupling (1.44 cm−1), both of which greatly improved the high triplet state yield (61 %), a state that determines the energy transfer to O2. Therefore, Secy7 demonstrated excellent 1O2 generation capacity, which is ~24.5‐fold that of indocyanine green, ~8.2‐fold that of IR780, and ~1.3‐fold that of methylene blue under low‐power‐density 850 nm irradiation (5 mW cm−2). Secy7 exhibits considerable phototoxicity toward cancer cells buried under 12 mm of tissue. Nanoparticles formed by encapsulating Secy7 within amphiphilic polymers and lecithin, demonstrated promising antitumor and anti‐pulmonary metastatic effects, exhibiting remarkable potential for advancing PDT in deep tissues. [ABSTRACT FROM AUTHOR]

Dual response polyurethane nanocapsules consisting of a hydrophilic core are synthesized via interfacial polyaddition of the diisocyanate monomers and different diols (VA‐060 and glycols) in inverse miniemulsion process. The presence of the water‐soluble NIR dye in the core and azo‐bonds in the polymer shell allows the selective release of encapsulated material triggered by temperature or NIR light. The capsules are characterized by transmission electron microscopy (TEM) and dynamic light scattering (DLS). The capsule degradation under external stimuli, like temperature and NIR light, is confirmed microscopically by TEM. Macroscopic evidence of the capsule cleavage was achieved by the incorporation of the chemical into the capsule core, and subsequent treatment of the capsules with NIR laser in the presence of the suitable reagent outside the capsules. A color‐forming chemical reaction occurred after the shell opening. The reactions were easily detected by visual observation of a color change and by UV–Vis spectroscopy. [ABSTRACT FROM AUTHOR]

Around 7% of the male population in the world are entangle with considerable situation which is known as male infertility. Photobiomodulation therapy (PBMT) is the application of low-level laser radiation, that recently used to increase or promote the various cell functions including, proliferation, differentiation, ATP production, gene expressions, regulation of reactive oxygen spices (ROS), and also boost the tissue healing and reduction of inflammation. This systematic review's main idea is a comprehensive appraisal of the literatures on subjects of PBMT consequences in four light ranges wavelength (blue, green, red, near-infrared (NIR)) on sperm cell characteristics, in vitro and in vivo. In this study, PubMed, Google Scholar, and Scopus databases were used for abstracts and full-text scientific papers published from 2003–2023 that reported the application of PBM on sperm cells. Criteria's for inclusion and exclusion to review were applied. Finally, the studies that matched with our goals were included, classified, and reported in detail. Also, searched studies were subdivided into the effects of four ranges of light irradiation, including the blue light range (400–500 nm), green light range (500–600 nm), red light range (600–780 nm), and NIR light range (780–3000 nm) of laser irradiation on human or animal sperm cells, in situations of in vitro or in vivo. Searches with our keywords results in 137 papers. After primary analysis, some articles were excluded because they were review articles or incomplete and unrelated studies. Finally, we use the 63 articles for this systematic review. Our category tables were based on the light range of irradiation, source of sperm cells (human or animal cells) and being in vitro or in vivo. Six% of publications reported the effects of blue, 10% green, 53% red and 31% NIR, light on sperm cell. In general, most of these studies showed that PBMT exerted a positive effect on the sperm cell motility. The various effects of PBMT in different wavelength ranges, as mentioned in this review, provide more insights for its potential applications in improving sperm characteristics. PBMT as a treatment method has significant effectiveness for treatment of different medical problems. Due to the lack of reporting data in this field, there is a need for future studies to assessment the biochemical and molecular effects of PBMT on sperm cells for the possible application of this treatment to the human sperm cells before the ART process. [ABSTRACT FROM AUTHOR]

Photocatalytic production of hydrogen peroxide (H2O2) has the advantages of safety, non-polluting operation and energy savings. Molecular-designed covalent organic frameworks (COFs) are an ideal material for achieving efficient photosynthesis of H2O2. However, the current COFs photocatalyst systems have various issues. Most of them harness only ultraviolet light and a small portion of visible light, unable to utilize 52% of the infrared (IR) light in the solar spectrum. Additionally, there are drawbacks such as the need for sacrificial agents and insufficient activity for large-scale production of H2O2. In this study, H2O2 production of 7.6 μmol h−1 was achieved using IR light irradiation without a sacrificial agent, and this photocatalyst ensured 6-times H2O2 production over Pristine COFs. The apparent quantum yield (AQY) under 900 nm light was 3.2%, which is 1.2-times higher than that when using Pristine COFs. This research outcome will contribute to the development of efficient and stable organic polymer photocatalysts for IR-driven H2O2 photocatalysis. [ABSTRACT FROM AUTHOR]

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[Display omitted] The dysregulation of microRNA (miRNA) expression levels is intricately linked to a myriad of human diseases, and the precise and delicate detection thereof holds paramount significance in the realm of clinical diagnosis and therapy. Herein, a near-infrared (NIR) light-mediated homogeneous photoelectrochemical (PEC) biosensor was constructed for miRNA-155 detection based on NaYF 4 : Yb, Tm@ZnIn 2 S 4 (NYF@ ZIS) coupled with a three-dimensional (3D) walking nanomotor-assisted CRISPR/Cas12a strategy. The upconverted light emitted by the NYF in the visible and UV region upon NIR light excitation could be utilized to excite ZIS to produce a photocurrent response. The presence of target miRNA-155 initiated an amplification reaction within the 3D walking nanomotor, resulting in the production of multiple nucleic acid fragments. These fragments could activate the collateral cleavage capability of CRISPR/Cas12a, leading to the indiscriminate cleavage of single-stranded DNA (ssDNA) on ALP-ssDNA-modified magnetic beads and the subsequent liberation of alkaline phosphatase (ALP). The released ALP facilitated the catalysis of ascorbic acid 2-phosphate to generate ascorbic acid as the electron donor to capture the photogenerated holes on the NYF@ZIS surface, resulting in a positively correlated alteration in the photocurrent response. Under optimal conditions, the NIR light-initiated homogeneous PEC biosensor had the merits of good linear range (0.1 fM to 100 pM), an acceptable limit of detection (65.77 aM) for miRNA-155 detection. Considering the pronounced sensitivity, light stability, and low photodamage, this strategy presents a promising platform for detecting various other miRNA biomarkers in molecular diagnostic practice. [ABSTRACT FROM AUTHOR]

Peripheral nerve repair remains a major clinical challenge, particularly in the pursuit of therapeutic approaches that ensure adequate recovery of patient’s activity of daily living. Autografts are the gold standard in clinical practice for restoring lost sensorimotor functions nowadays. However, autografts have notable drawbacks, including dimensional mismatches and the need to sacrifice one function to restore another. Engineered nerve guidance conduits have therefore emerged as promising alternatives. While these conduits show surgical potential, their clinical use is currently limited to the repair of minor injuries, as their ability to reinnervate limiting gap lesions is still unsatisfactory. Therefore, improving patient functional recovery requires a deeper understanding of the cellular mechanisms involved in peripheral nerve regeneration and the development of therapeutic strategies that can precisely modulate these processes. Interest has grown in the use of external energy sources, such as light, ultrasound, electrical, and magnetic fields, to activate cellular pathways related to proliferation, differentiation, and migration. Recent research has explored combining these energy sources with tailored nanostructured materials as nanotransducers to enhance selectivity towards the target cells. This review aims to present the recent findings on this innovative strategy, discussing its potential to support nerve regeneration and its viability as an alternative to autologous transplantation.

In the last decades, near‐infrared (NIR) light has attracted considerable attention due to its unique properties and numerous potential applications in bioimaging and disease treatment. Bone tissue engineering for bone regeneration with the help of biomaterials is currently an effective means of treating bone defects. As a controlled light source with deeper tissue penetration, NIR light can provide real‐time feedback of key information on bone regeneration in vivo utilizing fluorescence imaging and be used for bone disease treatment. This review provides a comprehensive overview of NIR light‐facilitated bone tissue engineering, from the introduction of NIR probes as well as NIR light‐responsive materials, and the visualization of bone regeneration to the treatment of bone‐related diseases. Furthermore, the existing challenges and future development directions of NIR light‐based bone tissue engineering are also discussed. This article is categorized under:Diagnostic Tools > In Vivo Nanodiagnostics and ImagingImplantable Materials and Surgical Technologies > Nanotechnology in Tissue Repair and Replacement [ABSTRACT FROM AUTHOR]

A series of glasses with chemical composition (50−x−y) TeO2–30ZnO–10YF3–10NaF–xHo2O3–yYb2O3 (x = 0.5 and y = 0.5, 1.0, 3.0, 5.0 mol%) were prepared by melt-quenching procedure. The absorption spectra, excitation, down conversion emission spectra, up-conversion (UC) emission spectra and decay time measurements were analyzed. In down conversion, the visible emission transition intensity associated with 5F4 → 5I8 (547 nm), 5F5 → 5I8 (657 nm), and 5F4 → 5I7 (755 nm) of Ho3+ ions decreased with Yb3+ concentration due to the energy transfer (ET) process from Ho3+ to Yb3+ ions. In up-conversion, on exciting with 980 nm diode laser beam, we observed a strong green (543 nm) and red (657 nm) UC emissions, that refers to the energy level transitions; 5F4 (5S2) → 5I8 and 5F5 → 5I8 of Ho3+. The influence of excitation power on UC intensities studies revealed that the population at 5F4 (5S2) and 5F5 levels of Ho3+ ion occurs due to two-photon absorption process associated energy transfer from Yb3+ to Ho3+. The influence of Yb3+ doped concentration on UC was studied, and it is observed that both the green and red UC intensities improved significantly on increasing Yb3+ ions concentration.

Conventional photocages only respond to short wavelength light, which is a significant obstacle to developing efficient phototherapy in vivo. The development of photocages activated by near‐infrared (NIR) light at wavelengths from 700 to 950 nm is important for in vivo studies but remains challenging. Herein, we describe the synthesis of a photocage based on a ruthenium (Ru) complex with NIR light‐triggered photocleavage reaction. The commercial anticancer drug, tetrahydrocurcumin (THC), was coordinated to the RuII center to create the Ru‐based photocage that is readily responsive to NIR light at 760 nm. The photocage inherited the anticancer properties of THC. As a proof‐of‐concept, we further engineered a self‐assembled photocage‐based nanoparticle system with amphiphilic block copolymers. Upon exposure to NIR light at 760 nm, the Ru complex‐based photocages were released from the polymeric nanoparticles and efficiently inhibited tumor proliferation in vivo. [ABSTRACT FROM AUTHOR]

The low utilization of solar energy due to the narrow response spectra limits the performance of current photocatalysts. Utilizing up-conversion photoluminescence is one of the effective methods to enhance photocatalytic ability. A new photocatalyst, NaYF4: Yb, Tm nanoparticles (NYT) embedded in NH2-MIL-125(Ti) (NYT@NH2-MIL-125(Ti)), was constructed aiming to efficiently degrade pollutant under full-spectrum illumination. The characterization certified that NYT had been successfully embedded in NH2-MIL-125(Ti). The photocatalytic activity of NYT@NH2-MIL-125(Ti) was tested by degrading Rhodamine B (RhB). The NYT@NH2-MIL-125(Ti) showed significantly enhanced photocatalytic activity compared with NH2-MIL-125(Ti), whose degradation kinetic constant of RhB was 3.73 times that of NH2-MIL-125(Ti). The enhanced photocatalytic performance should be attributed to the expanded response light spectra. Under illumination, NYT absorbs near-infrared (NIR) light and emits visible light, which stimulates NH2-MIL-125(Ti) to produce photo-generated electrons–holes. Free radical trapping experiments certified that holes(h+) plays a major role in the photocatalytic process. This work deepens the understanding of construction of high-efficiency photocatalyst with a broad spectrum response and promotes the application of photocatalysis in water pollution control. [ABSTRACT FROM AUTHOR]

Near-infrared (NIR) driven photodynamic therapy based on upconversion luminescent nanoparticles (UCNPs) is promising for fighting drug-resistant bacteria infections in deep tissues due to its good noninvasive, nonspecific, and non-drug-resistant properties, but is greatly limited by its low efficacy. Herein, honeycomb-silica-coated upconversion nanoparticles (UCNP@mSiO2) with a size of less than 100 nm were successfully prepared by a typical silica sol–gel reaction assisted with an expanding agent (p-xylene). The honeycomb silica shell has large pores with an average diameter of about 10 nm and large pore volume of 0.82 cm3/g and exhibits a MC540 loading as high as 9% in weight. The UCNP nanoparticle core can effectively capture NIR photons and activate the merocyanine 540 photosensitizer (MC540), generating reactive oxygen species to kill the drug-resistant bacteria of deep tissues. To avoid the drug prerelease, Ag nanoparticles in diameter close to that of the silica hole were covalently grafted onto the aminated UCNP@MC540@mSiO2 (UMS-NH2) nanoparticle. The Ag-decorated UMS-NH2 nanoparticles (UMSAg) showed synergistic antibacterial effects of Ag chemotherapy and photodynamic therapy and are more stable than undecorated UMS nanoparticles in an aqueous medium. The UMSAg with unreacted amino groups enhanced the binding of Ag to the bacterial membrane, effectively exerting the antibacterial effect of Ag+ and ROS. In in vitro antibacterial experiments, the killing rates of the UMSAg composite (150 μg/mL) against drug-resistant Staphylococcus aureus and drug-resistant Pseudomonas aeruginosa under NIR irradiation were 100% and 99.6%, respectively. In addition, the antibacterial activity of the UMSAg group was significantly higher than that of the sole Ag nanoparticles without irradiation. This work provides good insight for the design of efficient antibacterial agents and has a potential application for the bacterial infection of deep tissues. [ABSTRACT FROM AUTHOR]

• A mathematical methodology to find the optimal NIR light protocol in transdermal drug delivery; • Strategy based on an optimization problem minimizing the difference between target and simulated drug absorption profile; • The optimization problem relies on a 2D mathematical model for NIR light controlled transdermal drug delivery; • Validation of the transdermal model against laboratory data; • Convergence and stability analysis of a finite difference spatial scheme for a generalization of the transdermal model. Near-infrared light-controlled transdermal drug delivery (NIRTDD) has several advantages over traditional delivery methods, and it is now undergoing extensive research. One prominent aspect of NIRTDD is the possibility of keeping the drug concentration in its optimal therapeutic window using a suitable near-infrared light protocol. The problem is that this ideal protocol is usually unknown. In this paper, we propose a computational tool that aims at solving this issue. The computational tool relies on an optimization problem involving the numerical simulation of a two-dimensional mathematical model for NIRTDD. We also analyze the convergence and stability of a finite difference spatial scheme for a generalized version of this mathematical model. [ABSTRACT FROM AUTHOR]

CeF3-O with intermediate band showed improved synergic photodegradation activity toward HCl–TC and RhB under NIR light irradiation when enhanced by Ag as a cocatalyst. Ag+ ions take electrons from the second transition in CeF3–O's intermediate band, which are then reduced to Ag as cocatalyst. The photodegradation efficiencies of HCl–TC by various Ag/CeF3–O nanoparticles in 180-min increase from 26.5 to 73.1%. The optimal Ag/CeF3–O-100 is about 2.76 times that of pure CeF3–O. Ag/CeF3–O-100 has an apparent rate constant of 4.5 × 10−3 min−1, which is 3.0 times that of pure CeF3–O. Similarly, Ag/CeF3–O-10 achieves a superior photodegradation efficiency of RhB at 96.7% under NIR light within 120 min. Its apparent rate constant of 27.7 × 10−3 min−1 is 12.0 times that of pure CeF3-O (2.3 × 10−3 min−1). Further, the turnover frequencies of Ag/CeF3–O nanoparticles are greatly higher than that of the corresponding pure CeF3–O nanoparticles. Ag-enhanced CeF3–O has a unique metal–semiconductor interface where Ag acts as a bridge for facilitating charge transfer and the separation efficiency of photogenerated carries. The synergic effect between CeF3–O and Ag provides a practical technique for enhancing the wastewater treatment with NIR light irradiation. [ABSTRACT FROM AUTHOR]

Stable binary nanohybrids based on all‐inorganic halide perovskite encapsulated in porphyrinic Zr‐MOF (PCN‐222) are constructed for photoinduced electron transfer‐reversible addition‐fragmentation chain transfer (PET‐RAFT) polymerization. The synergistic effect of perovskite and PCN‐222 endows the photocatalyst with high‐efficiency photogenic charge carrier separation and light absorption property. CsPbI3@PCN‐222 (20%) is finally screened out as the oxygen and solvent‐resistant photocatalyst for highly efficient photo‐controlled polymerization of conjugated and unconjugated monomers under red to near infrared (NIR) light with high monomer conversion and narrow molecular weight distribution well‐defined polymers (Đ < 1.20). Controllable polymers and ultrahigh molecular weight polymers (up to 1730000 g mol−1) are successfully obtained by chain extension and block copolymerization of various monomers. The constructed photocatalysts easily achieve excellent light and temporal control, and even show high MMA conversion with NIR light under a thick barrier. [ABSTRACT FROM AUTHOR]

The possible charge transfer and promoted photothermal catalytic H 2 evolution mechanism of CuNi/CN. [Display omitted] It is challenging to maximize the utilization of solar energy using photocatalysis or photothermal catalysis alone. Herein, we report a full spectrum solar energy driven photothermal-assisted photocatalytic hydrogen production over CuNi bimetallic nanoparticles co-loaded with graphitized carbon nitride nanosheet layers (Cu x Ni y /CN) which are prepared by a facile in-situ reduction method. Cu 5 Ni 5 /CN shows a high hydrogen production rate of 267.8 μmol g−1 h−1 at room temperature, which is 70.5 and 1.34 times of that for pure CN (3.8 μmol g−1 h−1) and 0.5 wt% Pt/CN (216 μmol g−1 h−1), respectively. The photothermal catalytic hydrogen activity can be further increased by 3.7 times when reaction solution is external heated to 100 °C. For the photothermal catalytic system, the local surface plasmon resonance (LSPR) effect over active Cu nanoparticles can absorb near-infrared light to generate hot electrons, which are partially quenched to generate heat for heating of the reaction system and partially transported to the active sites, where the Ni nanoparticles as another functional component couple the electrons and heat to finally promote the photothermal catalytic activity. Our result suggests that a rational design of the catalyst with bifunctional atomic components can photothermocatalysis-assisted photocatalysis to maximize utilization solar energy for efficient full spectrum conversion. [ABSTRACT FROM AUTHOR]

Targeted, on‐demand delivery has been of interest using materials responsive to environmental stimuli. A delivery technique based on precise release of aqueous microdroplets from a liquid crystal (LC) medium with contactless stimulation is presented. A nematic LC is doped with a photothermal dye that produces heat under near IR light exposure. The heat is used to overcome the elastic strains in the LC phase, promoting the release of initially entrapped water droplets to the neighboring aqueous solution. Designing the geometry of LC‐based emulsions and tuning the light intensity and position allows for manipulation of the release in two distinct modes defined as pulsated and continuous. In the pulsated mode, water droplets are released transiently from the casted water‐in‐LC emulsion layer based on sweeping by the moving isotropic‐nematic phase boundary controlled by light. In the continuous mode, water droplets are ejected continuously from a droplet‐shaped water‐in‐LC emulsion, due to a heating‐induced internal flow controlled by light. The droplet release by contactless stimulation is used for the on‐demand dosing of dopamine and its oxidizing reagent from isolated reservoirs to obtain an in situ reaction signal for a hydrogen peroxide assay. A new dual‐mode release system developed with photothermal LCs holds potential in drug release, controlled mixing, and photothermal therapy. [ABSTRACT FROM AUTHOR]

Purpose: Photobiomodulation (PBM) promotes diabetic wound healing by favoring cell survival and proliferation. This study aimed to investigate the potential of PBM in stimulating cellular migration, viability, and proliferation using the transforming growth factor-β 1 (TGF-β 1)/Smad signaling pathway. Methods: The study explored the in vitro effects of near infrared (NIR) light on cell viability (survival) and proliferation as well as the presence of TGF-β 1, phosphorylated TGF‐β receptor type I (pTGF-βR1) and phosphorylated mothers against decapentaplegic‐homolog (Smad)‐2/3 (p-Smad2/3) in different fibroblast cell models. Results: Results show a significant increase in cellular migration in wounded models, and increased viability and proliferation in irradiated cells compared to their respective controls. An increase in the presence of TGF-β 1 in the culture media, a reduction in pTGF-βR1 and a slight presence of p-Smad2/3 was observed in the cells. Conclusion: These findings show that PBM at 830 nm using a fluence of 5 J/cm2 could induce cell viability, migration and proliferation to favor successful healing of diabetic wounds. This study contributes to the growing body of knowledge on the molecular and cellular effect of PBM and showcases the suitability of PBM at 830 nm in managing diabetic wounds. [ABSTRACT FROM AUTHOR]

The use of cheap and safe near-infrared (NIR) light is still the subject of intense research efforts but remains a huge challenge due to the associated low photon energy (wavelength from 0.78 to 2.5 µm). In this study, a series of 17 NIR dyes mainly based on a well-established cyanine scaffold is proposed. Remarkably, 11 of them were never synthesized before. Markedly, noncharged structures, negatively charged cyanine bearing Na+ as counter cation, and positively charged cyanines bearing (B(Ph)4−) or (I−) as counter anions were examined as promising NIR light photoinitiating systems. Excellent photoinitiating abilities were found for some reported dyes when used in combination with iodonium salt and amine. Markedly, photothermal effects with a huge heater behavior were also observed for different NIR dye structures. Interestingly, the synthesis of interpenetrating polymer networks (IPNs, e.g., for the polymerization of acrylate/epoxy monomer blends) can also be carried out upon NIR light with the proposed systems.

• Excited at 520 nm light, the designed phosphor can emit broad NIR emission peaking at 876 nm. • The luminescence properties of studied samples are improved by constructing Sc3+ vacancy. • Based on FWHM value, the maximum S a and S r values are 42.61 % and 0.16 % K−1, respectively. • The fabricated NIR LED using designed phosphors exhibits various applications. Near-infrared (NIR) emitting phosphors exhibit admirable photophysical performances which enable their promising application in various fields, whereas the development of a broad NIR emitting phosphors with high performance is still a challenge. Herein, series of Ca 2.94 Sc 2- x Si 3 O 12 :0.06Eu2+ (Ca 3 Sc 2- x Si 3 O 12 :Eu2+) garnet NIR emitting phosphors were designed and the defect engineering was used to regulate the luminescence properties. Upon 520 nm excitation, the resulting phosphors emit intense broad NIR emission peaking at 876 nm arising from Eu2+. Through decreasing Sc3+ content, the defect (i.e. Sc3+ vacancy) was formed and it can efficiently increase the luminescence characteristics of designed compounds, in which Ca 3 Sc 1.9 Si 3 O 12 :Eu2+ phosphor possess the strongest intensity. Moreover, based on density functional theory, theoretical calculation was performed to verify the existence of Sc3+ vacancy in studied samples. Furthermore, the fluorescence intensity and full-width at half maximum (FWHM) were all dependent on temperature. Through analyzing the temperature-dependent FWHM value, it was found that the maximum absolute and relative sensitivities were 42.61 % and 0.16 % K−1, respectively. Via utilizing the synthesized phosphors as NIR converters, a new NIR light-emitting diode (LED) was packaged and it presented potential applications in food detection, bioimaging, NIR solid-state lighting and night-vision. Our findings proposed an efficient strategy to manipulate the luminescence properties of NIR emitting phosphors via constructing defect so as to realize their vivid applications. [ABSTRACT FROM AUTHOR]

Cancer stem-like cells (CSCs) have a well-established role in mediating tumor relapse and resistance towards chemotherapy and radiation therapy. Photothermal therapy (PTT) is an efficient therapeutic strategy that uses light and photothermal agents to generate hyperthermia in tumors and kill cancer cells. However, due to the heterogeneity and drug resistance of CSCs, some of them may survive from PTT and cause recurrence and metastasis of tumors. In the study, we present a sequential dual-wavelength light-controlled drug delivery strategy, which combines 656 nm light-triggered drug release to inhibit cancer stemness, followed by 808 nm light-activated PTT to eradicate bulk tumors. The first light irradiation induces the release of γ-secretase inhibitor MK-0752 to deactivate Notch pathway, which is a key regulator of CSCs. Subsequently, the second light irradiation triggers hyperthermia to effectively kill tumor cells. Our findings demonstrate that inhibiting cancer stemness increases tumor sensitivity to PTT, resulting in effective growth inhibition of primary tumors with repressed tumorgenicity. This innovative dual-wavelength strategy holds promise for enhancing the efficacy of PTT in addressing the challenges posed by CSCs-rooted heterogeneity and drug resistance. [Display omitted] Notch pathway deactivation sensitizing cancer stem cells to photothermal therapy Newly designed near-infrared light-activatable prodrug A carrier-free self-assembled nanoparticle to co-deliver two therapeutic agents Dual-wavelength light to control separate drug functions Sequential light irradiation for maximized anti-tumor efficacy [ABSTRACT FROM AUTHOR]

Photolabile Protecting Groups (PPGs) are molecular tools used, for example, in photopharmacology for the activation of drugs with light, enabling spatiotemporal control over their potency. Yet, red‐shifting of PPG activation wavelengths into the NIR range, which penetrates the deepest in tissue, has often yielded inefficient or insoluble molecules, hindering the use of PPGs in the clinic. To solve this problem, we report herein a novel concept in PPG design, by transforming clinically‐applied NIR‐dyes with suitable molecular orbital configurations into new NIR‐PPGs using computational approaches. Using this method, we demonstrate how Cy7, a class of NIR dyes possessing ideal properties (NIR‐absorption, high molecular absorptivity, excellent aqueous solubility) can be successfully converted into Cy7‐PPG. We report a facile synthesis towards Cy7‐PPG from accessible precursors and confirm its excellent properties as the most redshifted oxygen‐independent NIR‐PPG to date (λmax=746 nm). [ABSTRACT FROM AUTHOR]

Near‐infrared (NIR) light plays an increasingly important role in the field of photoinduced electron/energy transfer‐reversible addition–fragmentation chain transfer (PET‐RAFT) polymerization due to its unique properties. Yet, the NIR photocatalyst with good stability for PET‐RAFT polymerization remains promising. Here, a strategy of NIR PET‐RAFT polymerization of semifluorinated monomers using fluorophenyl bacteriochlorin as a photocatalyst with strong absorption at the NIR light region (710–780 nm) is reported. In which, the F atoms are used to modify reduced tetraphenylporphyrin structure with enhanced photostability of photocatalyst. Under the irradiation of NIR light (λmax = 740 nm), the PET‐RAFT polymerization of semifluorinated methylacrylic monomers presents living/control characteristics and temporal modulation. By the PET‐RAFT polymerization‐induced self‐assembly (PISA) strategy, stable fluorine‐containing micelles are constructed in various solvents. In addition, the fluorinated hydrophobic surface is fabricated via a surface‐initiated PET‐RAFT (SI‐PET‐RAFT) polymerization using silicon wafer bearing RAFT agents with tunable surface hydrophobicity. This strategy not only enlightens the application of further modified compounds based on porphyrin structure in photopolymerization, but also shows promising potential for the construction of well‐defined functional fluoropolymers. [ABSTRACT FROM AUTHOR]

Optical control of protein activity represents a promising strategy for precise modulation of biological processes. We report rationally designed, aptamer‐based spherical nucleic acids (SNAs) capable of noninvasive and programmable regulation of target protein activity by deep‐tissue‐penetrable near‐infrared (NIR) light. The photoresponsive SNAs are constructed by integrating activatable aptamer modules onto the surface of upconversion nanoparticles. The SNAs remain inert but can be remotely reverted by NIR light irradiation to capture the target protein and thus function as an enzyme inhibitor, while introduction of antidote DNA could further reverse their inhibition functions. Furthermore, we demonstrate the potential of the SNAs as controllable anticoagulants for the NIR light‐triggered regulation of thrombin function. Ultimately, the availability of diverse aptamers would allow the design to regulate the activities of various proteins in a programmable manner. [ABSTRACT FROM AUTHOR]

Bacterial contamination is a severe issue that affects medical devices, hospital tools and surfaces. When microorganisms adhere to a surface (e.g., medical devices or implants) they can develop into a biofilm, thereby becoming more resistant to conventional biocides and disinfectants. Nanoparticles can be used as an antibacterial agent in medical instruments or as a protective coating in implantable devices. In particular, attention is being drawn to photothermally active nanoparticles that are capable of converting absorbed light into heat. These nanoparticles can efficiently eradicate bacteria and biofilms upon light activation (predominantly near the infrared to near-infrared spectral region) due a rapid and pronounced local temperature increase. By using this approach new, protective, antibacterial surfaces and materials can be developed that can be remotely activated on demand. In this review, we summarize the state-of-the art regarding the application of various photothermally active nanoparticles and their corresponding nanocomposites for the light-triggered eradication of bacteria and biofilms.

The high penetration of near‐infrared (NIR) light makes it effective for use in selective reactions under light‐shielded conditions, such as in sealed reactors and deep tissues. Herein, we report the development of phthalocyanine catalysts directly activated by NIR light to transform small organic molecules. The desired photocatalytic properties were achieved in the phthalocyanines by introducing the appropriate peripheral substituents and central metal. These phthalocyanine photocatalysts promote cross‐dehydrogenative‐coupling (CDC) under irradiation with 810 nm NIR light. The choice of solvent is important, and a mixture of a reaction‐accelerating (pyridine) and ‐decelerating (methanol) solvents was particularly effective. Moreover, we demonstrate photoreactions under visible‐light‐shielded conditions through the transmission of NIR light. A combined experimental and computational mechanistic analysis revealed that this NIR reaction does not involve a photoredox‐type mechanism with electron transfer, but instead a singlet‐oxygen‐mediated mechanism with energy transfer. [ABSTRACT FROM AUTHOR]

Cracks formed in materials can influence the performances and shorten their lifetime. Self‐healing materials can repair cracks caused by mechanical damage using external stimuli, which increases their safety, extend their service life, and can save renovation costs. In this work, a novel thermo‐responsive linear Diels‐Alder polyurethane (DAPU) and reduced tungsten oxide (WO3−x) (W‐DAPU) is developed for the first time. Its near‐infrared (NIR) light‐induced self‐healing properties are evaluated using qualitative optical observation and quantitative tensile measurements. The NIR light‐induced self‐healing and photothermal conversion property of W‐DAPU is also systematically investigated. The results show that linear DAPU has an excellent thermo‐reversible self‐healing efficiency of 94.8% and heals within 6 s due to the presence of a DA bond. In addition, the W‐DAPU has a self‐healing efficiency of 83.2% with outstanding photothermal conversion. This study paves the way to design and fabricate stimuli‐responsive nanocomposite materials for various applications. [ABSTRACT FROM AUTHOR]

Uranium, as the most essential resource for nuclear power production, provides 13% of global electricity demand, has attracted considerable attention. However, it is still a great challenge for uranium extraction from natural water like salt lakes as the background of high salinity and low concentration (3.3 ∼ 330 ppb). Meanwhile, current uranium extraction strategies are generally focus on extraction capacity or selectivity but neglect to enhance extraction rate. In this work, we designed a novel kind of NIR-driven intelligent nanorobots catchers (MSSA-AO) with amidoxime as claws for uranium capture, which showed almost 100% extraction rate and an ultrafast extraction rate. Importantly, high extraction capacity (221.5 mg g−1) and selectivity were taken into consideration as well as good regeneration performance. Furthermore, amidoxime NRCs boosted in extraction amount about 16.7% during the first 5 min with self-driving performance. Overall, this work suggests a new strategy for ultrafast extraction of uranium from natural water with low abundance selectively by self-propelled NRCs, showing great possibility in outdoor application and promising for meeting huge energy needs globally. [Display omitted] • An intelligent nanorobot catchers (MSSA-AO) with self-navigation and self-targeting were designed for uranium extraction. • MSSA-AO was propelled by NIR light, showing easy motion controllability and sustainability. • Motion speed and direction of MSSA-AO is controllable and free from limitation of chemical fuel. • MSSA-AO demonstrated advantages in adsorption capacity and selectivity towards uranium. [ABSTRACT FROM AUTHOR]

Photopolymerization refers to a type of polymerization process in which light is utilized as excitation source to initiate polymerization of monomers and oligomers. Despite great progress, photopolymerization is typically induced by ultraviolet or visible light, which still greatly restrains its applications. Upconversion nanoparticles (UCNPs) represent a class of optical nanomaterials that are able to convert low‐energy near‐infrared (NIR) light into high‐energy ultraviolet (or visible light) emissions. In this context, UCNP‐assisted photopolymerization has recently attracted extensive attentions due to its unique advantages. In this account, recent advances in the fundamentals, optimization and emerging applications of UCNP‐based photopolymerization are reviewed. Fundamental theories of upconversion luminescence and photopolymerization will be introduced first. Various optimization approaches to improve UCNP‐assisted photopolymerization are then summarized, followed by diverse emerging applications. Challenges and future perspectives in this area will be provided as a conclusion. [ABSTRACT FROM AUTHOR]

Daily management of arteriovenous fistula for dialysis patients is crucially important because it sometimes leads to stenosis and obstruction. Numerous shortcomings are associated with management techniques used today. Aside from being invasive, they also require the use of inspection, auscultation, and palpation. Moreover, they rely on the extensive experience of technicians. Actually, definite diagnosis can be made using angiography, but angiography entails difficulties associated with radiation and bulky equipment. To overcome these difficulties posed by current management techniques, we proposed an optical imaging technique. Unfortunately, the related apparatus was too large and heavy for bedside use. This paper therefore explains the possibility of clinical application of our novel technique using compact and light apparatus. Contrast of blood vessel transillumination images is intensified with two wavelengths used for measurements. Results indicate improved accuracy of inner diameter measurements of blood vessels. This study confirmed the possibility of applying this technique in medical settings to achieve continuous management of AV fistula. [ABSTRACT FROM AUTHOR]

Understanding of the functions of enzymes in diverse cellular processes is important, but the design of sensors with controllable localization for in situ imaging of subcellular levels of enzymatic activity is particularly challenging. We introduce herein a spatiotemporally controlled sensor technology that permits in situ localization and photoactivated imaging of human apurinic/apyrimidinic endonuclease 1 (APE1) within an intracellular organelle of choice (e.g. mitochondria or nucleus). The hybrid sensor platform is constructed by photoactivatable engineering of a DNA‐based fluorescent probe and further combination with an upconversion nanoparticle and a specific organelle localization signal. Controlled localization and NIR‐light‐mediated photoactivation of the sensor "on demand" effectively constrains the imaging signal to the organelle of interest, with improved subcellular resolution. We further demonstrate the application of the nanosensors for the imaging of subcellular APE1 translocation in response to oxidative stress in live cells. [ABSTRACT FROM AUTHOR]

Herein, we report near‐infrared (NIR) light‐driven shape‐morphing of programmable MXene‐containing anisotropic hydrogel actuators that are fabricated through in situ free‐radical copolymerization of a judiciously designed MXene nanomonomer with thermosensitive hydrogel network. A low electric field (few V mm−1) was found to enable a spatial distribution of MXene nanosheets and hence introduce anisotropy into the hydrogel network. Programmable anisotropic hydrogel actuators were developed by controlling ITO electrode pattern, direct‐current (DC) electric field direction and mask‐assisted photopolymerization. As a proof‐of‐concept, we demonstrate NIR light‐driven shape morphing of the MXene‐containing anisotropic hydrogel into various shapes and devise a four‐arm soft gripper that can perform distinct photomechanical functions such as grasping, lifting/lowering down and releasing an object upon sequential NIR light exposure. [ABSTRACT FROM AUTHOR]

Photoinduced thermal polymerization upon Near‐InfraRed (NIR) light has been recently reported in the literature as an efficient tool for polymer synthesis. In this work, a completely different approach is developed since polymeric materials containing a very low amount of a stimuli‐responsive compound are prepared by using a benchmark UV photoinitiator. As the stimuli‐responsive compound, an organic dye strongly absorbing in the near‐infrared region is selected. The heat released by its irradiation with an inexpensive and highly penetrating NIR light source allows the development of an unprecedented approach for reprocessing, reshaping, recycling, and self‐healing. Several parameters have been studied in order to determine their influence on the polymer temperature: the wavelength of the NIR irradiation, the irradiance of the NIR light source, the choice of heater (IR‐813 p‐toluenesulfonate or a squaraine dye), and the heater concentration. The thermoplastics bonding and debonding has also been studied and showed promising results since two pieces of polymers could be pasted together after a short time of NIR irradiation. Finally, self‐healing ability of the thermoplastic is investigated and furnished impressive results even for large scratches. [ABSTRACT FROM AUTHOR]

Distinguishing the contributions from localized surface plasmon resonance (LSPR)induced photothermal effect is a significant challenge in the study of solar hydrogen production. Herein, a well‐defined one‐dimensional Cu/TiO2 heterostructure with Cu size of 3–6 nm is designed to address such issue. Cu nanoparticles present notable LSPR absorption from visible to near‐infrared light, while no hydrogen is produced in the presence of simulated light with λ ≥ 700 nm. Interestingly, a remarkable improvement of hydrogen evolution under full‐spectrum light was observed which is almost twice of that under only ultraviolet–visible light irradiation, implying the critical yet auxiliary role of LSPR‐induced photothermal effect in promoting photocatalytic performance. Significantly, a notable reduction of the apparent activation energy and strengthened charge separation efficiency are observed due to the increased local temperature of catalyst surface caused by the plasmon‐induced photothermal effect. The kinetic and thermodynamic changes should be responsible for the enhanced hydrogen production. [ABSTRACT FROM AUTHOR]

In the present study, chiral CuxCoyS nanoparticles (NPs) were developed to selectively induce apoptosis of senescent cells using both an alternating magnetic field (AMF) and near infrared (NIR) photon illumination. The chiral effects on living cells were investigated, and d‐CuxCoyS NPs showed about 2.5 times higher of internalized ability than l‐NPs. By modifying beta 2 macroglobulin (MG), senescent cells were effectively eliminated by d‐CuxCoyS NPs without damaging the activities of normal cells under AMF and photon illumination. Compared to the individual application of NIR illumination and AMF, their synergistic effect induced the production of caspase‐3 with a much shorter treatment time and higher efficiency due to the more serious photon‐induced cellular redox and mechanical damage of cellular skeleton. Moreover, the developed strategy was successfully used to remove senescent cells in vivo. This study developed a controllable way of regulating cell activities using chiral NPs, which will provide a valuable way for treating diseases and promoting health. [ABSTRACT FROM AUTHOR]

Herein, near‐infrared (NIR) photocontrolled iodide‐mediated reversible‐deactivation radical polymerization (RDRP) of methacrylates, without an external photocatalyst, was developed using an alkyl iodide (e.g. 2‐iodo‐2‐methylpropionitrile) as the initiator at room temperature. This example is the first use of a series of special solvents containing carbonyl groups (e.g. 1,3‐dimethyl‐2‐imidazolidinone) as both solvent and catalyst for photocontrolled RDRP using long‐wavelength (λmax=730 nm) irradiation. The polymerization system comprises monomer, alkyl iodide initiator, and solvent. Well‐defined polymers were synthesized with excellent control over the molecular weights and molecular weight distributions (Mw/Mn<1.21). The living features of this system were confirmed by polymerization kinetics, multiple controlled "on‐off" light switching cycles, and chain extension experiments. Importantly, the polymerizations proceeded successfully with various barriers (pork skin and A4 paper), demonstrating the advantage of high‐penetration NIR light. [ABSTRACT FROM AUTHOR]

[Display omitted] • Multi-branched AgAuPt is synthesized for cooperative system electrocatalysis. • The role of light and heat in enhancing catalytic activity is discussed separately. • The dynamic situation in catalytic processes is discussed and elucidated. • The proposed mechanism is explained in terms of the hopping rate of polarons. Electrocatalytic hydrogen evolution reaction (HER) represents a potential technology to solve environmental and energy concerns. However, the high overpotentials and sluggish kinetics remain an essential challenge for electrocatalytic HER. Being different from the complicated strategies of electrocatalyst preparation, the present study focuses on a simple and feasible approach to improve electrocatalytic HER activity through a cooperative catalytic system. Here, we report a kind of multi-branched AgAuPt plasmonic heterojunction. Under the irradiation of 808 nm near-infrared (NIR) light, the localized surface plasmon resonance (LSPR) effect and the photothermal effect induce magnetic field and increased temperature, and achieve electro-optical-magnetic-thermal coupling in the catalysts. In addition, the dynamic process of the cooperative catalytic system is investigated as the temperature gradually changes. The proposed mechanism of the dynamic process is discussed in terms of the hopping rate of polarons (K p). This work provides novel insights and inspirations into the design of cooperative catalytic system with improved electrocatalytic HER activity. [ABSTRACT FROM AUTHOR]

Multidrug-resistant (MDR) bacterial infections have become major threats to public health worldwide. To address this challenge, nanozyme with intrinsic enzyme-like activity has been used that can serve as broad-spectrum antibiotics. However, the efficacy of individual nanozyme is hindered by its limited catalytic activity and therapeutic efficiency. In this study, we develop broad-spectrum antibacterial nanocomposites, namely IrOx@PDA NPs-RSNO (IP NPs-RSNO), which demonstrate remarkable efficacy in eradicating MDR bacteria. The excellent antibacterial performance of IP NPs-RSNO is attributed to the synergistic effects of NIR photothermal property, NIR-enhanced peroxidase-like (POD-like) activity, and NIR-triggered release of NO. IP NPs-RSNO can effectively eliminate carbapenem-resistant Escherichia coli (CREC) and methicillin-resistant Staphylococcus aureus (MRSA), showing excellent therapeutic performance in treating MRSA-infected wounds. This work provides insights into the design of multifunctional nanozymes for antibacterial applications. [Display omitted] • IP NPs-RSNO as a multifunctional nanocomposite for broad-spectrum antibacterial therapy exhibited exceptional efficacy in eradicating MDR bacteria for antibacterial therapeutics. • The remarkable performance of IP NPs-RSNO was attributed to the synergistic interplay of (1) NIR photothermal property; (2) NIR-enhanced peroxidase-like activity; (3) NIR-triggered release of NO. • IP NPs-RSNO had demonstrated the ability to effectively eliminate bacterial strains such as 99.99 % CREC and 99.98 % MRSA within 5 minutes, showing outstanding therapeutic performance in treating MRSA-infected wounds. [ABSTRACT FROM AUTHOR]

Abstract Upconversion is a nonlinear optical phenomenon that involves the emission of high‐energy photons by sequential absorption of two or more low‐energy excitation photons. Due to their excellent physiochemical properties such as deep penetration depth, little damage to samples, and high chemical stability, upconversion nanoparticles (UCNPs) are extensively applied in bioimaging, biosensing, theranostic, and photochemical reactions. Here, recent achievements in the synthesis, optimization, and applications of UCNP‐based nanomaterials are reviewed. The state‐of‐the‐art approaches to synthesize UCNPs in the past few years are introduced first, followed by a summary of several strategies to optimize upconversion emissive properties and various applications of UCNPs. Lastly, the challenges and future perspectives of UCNPs are provided as a conclusion.

• Two representative thermochromic windows for NIR and visible transmittance control respectively were selected. • Comprehensive analyses for the selected thermochromic windows were conducted at three different climates. • Both energy efficient and indoor luminance environmental can be improved with the use of NIR and VIS control thermochromic windows. • Building energy saving over 50% can be achieved with the proper TC applied compared with traditional double glazing. Thermochromic (TC) windows are able to adjust solar radiation transmitted into buildings in response to varying window surface temperature. Vanadium Dioxide (VO 2) is the most common TC material used for TC windows, as it can reduce near infrared (NIR) solar transmittance to attenuate undesirable solar heat gains during hot days when window surface temperature rises above a particular transition temperature. However, there have been few studies of the effect of TC windows on the indoor luminous environment. In order to improve daylight control, an innovative Iron-liquid based TC window film, which can control the visible (VIS) spectrum was introduced and applied alongside a VO 2 based TC material in this study. The combined performance of these two types of TC material was evaluated under three climatic conditions within China: Beijing, Shanghai and Guangzhou. The results show that increasing either the NIR or visible transmittance difference after switching, is beneficial for thermochromic performance, the maximum energy saving increasing from 11% to 18%, and UDI 500–2000 lx increasing by up to 27%. Combined application of NIR and visible spectral selection results in improved balance between energy demand and daylight provision. It was found that the energy saving potential and daylighting regulating capability offered by the combined implementation is highly dependent on matching the climate conditions to the TC windows. [ABSTRACT FROM AUTHOR]