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Objectives Varicose veins that cannot be seen with the naked eye can be easily detected with Near Infrared (NIR) light. With a minimally invasive procedure performed with NIR light guided, the need for reoperation is reduced, while optimal treatment of venous insufficiency and symptoms is provided. In this study, the detection of residual varicose veins after varicose vein surgery using NIR light and the results of treatment of sclerotherapy were investigated. Methods In this retrospective study, treatment and clinical outcomes of patients’ who underwent NIR light-guided foam sclerotherapy for Clinical-Etiology-Anatomy-Pathophysiology (CEAP) (C1, C2) stage residual varicose veins after surgical varicose treatment between 2014 and 2017 were examined. Data of patients who underwent foam sclerotherapy with NIR light were collected and analyzed. Results A total of 151 patients and 171 lower extremity varicose veins were treated with surgery. 55 (35.7%) of the patients were male, and 96 (62.3%) were female. Their age ranges from 20 to 64, with an average age of 45.38. 4 (2.6%) of the patients had phlebectomy. 137 of patients (90.7%) had ligation of perforated veins, phlebectomy, and great saphenous vein (GSV) stripping, 10 of patients (6.6%) had GSV stripping, perforating vein ligation, phlebectomy, and small saphenous vein (SSV) surgery. No residual leakage was observed in the controls of GSV, SSV, and perforating veins by duplex ultrasonography (DUS). In the first month after varicose surgery, an average of 1.64 ± 1.05 sessions of sclerotherapy was applied to patients with CEAP C1, C2 stage residual varicose veins. 70 patients had one session of sclerotherapy, 37 patients had two sessions of sclerotherapy, 20 patients had three sessions of sclerotherapy, and 11 patients had four sessions of sclerotherapy administrated. The need for complementary therapy was required for all female patients; 13 of the male patients did not require complementary sclerotherapy. While single-session sclerotherapy was applied to most male patients (32 (58.18%), 10 (18.18%) patients received two sclerotherapy sessions. After completing sclerotherapy, 7 (4.63%) patients had superficial venous thrombosis, and 13 (8.60%) patients had hyperpigmentation. Conclusion Surgical treatment is a safe and effective technique in venous insufficiency. Nevertheless, residual varicose veins may remain, and these can be detected noninvasively with NIR light. Foam sclerotherapy with NIR light is a minimally invasive and safe treatment method for small residual varicose veins after the operation. We think that sclerotherapy with NIR light as a complementary treatment is a practical, reliable, and demanding treatment for clinical improvement, especially in female patients.

The significance of NIR light-absorbing and/or emitting materials is growing day by day in industrial applications as well as research fields because of intrinsic versatility of NIR light. The uniq...

"On-demand" accurate imaging of multiple intracellular miRNAs will significantly improve the detection reliability and accuracy. However, the "always-active" design of traditional multicomponent detection probes enables them to passively recognize and output signals as soon as they encounter targets, which will inevitably impair the detection accuracy and, inevitably, result in false-positive signals. To address this scientific problem, in this work, we developed a near-infrared (NIR) light-activated multicomponent detection intelligent nanoprobe for spatially and temporally controlled on-demand accurate imaging of multiple intracellular miRNAs. The proposed intelligent nanoprobe is composed of a rationally designed UV light-responsive triangular DNA nano sucker (TDS) and upconversion nanoparticles (UCNPs), named UCNPs@TDS (UTDS), which can enter cells autonomously through endocytosis and enable remote regulation of on-demand accurate imaging for multiple intracellular miRNAs using NIR light illumination at a chosen time and place. It is worth noting that the most important highlight of the UTDS we designed in this work is that it can resist nonspecific activation as well as effectively avoid false-positive signals and improve the accuracy of imaging of multiple intracellular miRNAs. Moreover, distinguishing different kinds of cell lines with different miRNA expressions levels can be also achieved through this NIR light-activated intelligent UTDS, showing feasible prospects in precise imaging and disease diagnosis.

Additive manufacturing of food is a method of creating three-dimensional edible products layer-by-layer. While food printers have been in use since 2007, commercial cooking appliances to simultaneously cook and print food layers do not yet exist. A key challenge has been the spatially controlled delivery of cooking energy. Here, we explore precision laser cooking which offers precise temporal and spatial control over heat delivery and the ability to cook, broil, cut and otherwise transform food products via customized software-driven patterns, including through packaging. Using chicken as a model food, we combine the cooking capabilities of a blue laser (λ = 445 nm), a near-infrared (NIR) laser (λ = 980 nm), and a mid-infrared (MIR) laser (λ = 10.6 μm) to broil printed chicken and find that IR light browns more efficiently than blue light, NIR light can brown and cook foods through packaging, laser-cooked foods experience about 50% less cooking loss than foods broiled in an oven, and calculate the cooking resolution of a laser to be ~1 mm. Infusing software into the cooking process will enable more creative food design, allow individuals to more precisely customize their meals, disintermediate food supply chains, streamline at-home food production, and generate horizontal markets for this burgeoning industry.

It is hard to achieve safe, effective, and minimally invasive therapies on myocardial infarction (MI) via conventional treatments. To address this challenge, a vascular endothelial growth factor (VEGF)-loaded and near-infrared (NIR)-triggered self-unfolding graphene oxide (GO)-poly(vinyl alcohol) (PVA) microneedle (MN) patch was designed and fabricated to treat MI through a minimally invasive surgery (MIS). The folded MN patch can be easily placed into the chest cavity through a small cut (4 mm) and quickly recover to its original shape with 10 s of irradiation of NIR light (1.5 W/cm2, beam diameter = 0.5 cm), thanks to its excellent shape memory effect and fast shape recovery ability. Meanwhile, the unfolded MN patch can be readily punctured into the heart and wrap the heart tightly, thanks to its sufficient mechanical strength and adjustable morphological structure, thus ensuring a high fixation strength to withstand the high-frequency pulsation of the heart. In addition, the prepared MN patch has low cytotoxicity and controllable and sustainable release of VEGF. More importantly, the MN patch can effectively promote neovascularization, reduce myocardial fibrosis, and restore cardiac function, which indicates its promising application prospects in MIS.

We designed novel biocompatible nanocomposite composed of gold nanorods coated with rod-like mesoporous silica SBA-15-SH particles, (GNRs@SBA-15-SH) as a new synergistic therapeutic device to deliver heat and drug to cancer cells for tumor eradication. For this purpose, doxorubicin (DOX) was loaded into GNRs@SBA-15-SH nanocomposites and studied their photothermal therapy, chemotherapy and the combined effect on the ablation of A549 cells in vitro using human lung cancer cells, A549. The results demonstrate the high photothermal efficacy of gold nanorods loaded into the nanocomposite, the thermo-responsive properties of GNRs@SBA-15-SH, the high loading capacity of DOX into the GNRs@SBA-15-SH and its biocompatibility. Synergistic chemo-photothermal of the GNRs@SBA-15-SH/DOX nanocomposite in the eradication of cancer cells under laser irradiation (808 nm), demonstrates the high potential of therapeutic efficacy of this combined therapy over monotherapies.

Current cancer therapy has been restricted by the hypoxic microenvironment of tumors, especially for strongly oxygen-dependent photodynamic therapy. To defeat tumor hypoxia, an oxygen-irrelevant radical nanogenerator, PI/FBC, is developed by the co-assembly of iodized polymer PI and NIR photosensitizer FBC, and further evaluated as a remote controllable free radical generation platform for enhancing antitumor efficiency. The PI/FBC radical nanogenerator can be excited by NIR light to produce ROS through transfer of energy to oxygen and induce the formation of toxic iodine radicals via electron transfer to PI. Notably, unlike conventional tumor treatments, such a radical nanogenerator is controllable and insusceptible to oxygen concentration. Moreover, benefiting from the strong NIR emission of FBC, the distribution of the PI/FBC radical nanogenerator can be monitored without incorporating other imaging agents. This PI/FBC radical nanogenerator treatment will no doubt broaden the family of antitumor strategies by using non-oxygen radicals, which is significant for reference in the development of promising anticancer agents., An iodized polymer-based radical nanogenerator, PI/FBC, with strong NIR emission was prepared for NIR-mediated hypoxia-irrelevant tumor therapy.

Thermoresponsive polymers incorporated with photo-absorbing agents have been widely utilized for controlled drug delivery using light as an external stimulus. However, previously developed thermoresponsive drug carriers have disadvantages such as low biocompatibility and implantation failure. In the present study, gold nanorods (GNRs)-encapsulated poly(N-vinyl caprolactam) (PVCL) (GNR-PVCL) microparticles were synthesized by the stop-flow lithography (SFL) method. The SFL method enabled the fabrication of near-infrared (NIR) light-responsive GNR-PVCL microparticles of uniform size, which can allow localized injection. Doxorubicin (DOX) was encapsulated into GNR-PVCL microparticles to achieve NIR light-responsive anticancer therapy. DOX-loaded GNR-PVCL (DOX-GNR-PVCL) microparticles exhibited NIR light-triggered drug release due to the photothermal effect of GNRs, which increases the local temperature above the volume phase transition temperature of GNR-PVCL microparticles. In addition, DOX-GNR-PVCL exhibited controlled DOX release in response to the periodic irradiation of NIR light. Moreover, we demonstrated the efficient intracellular release of DOX upon NIR light exposure, and thus, NIR light-responsive anticancer activity. This study demonstrates that DOX-GNR-PVCL microparticles have significant potential as implantable drug carriers enabling NIR light-triggered drug release.

Phototherapeutic approaches, including photothermal therapy (PTT) and photodynamic therapy (PDT), have become a promising strategy to combat microbial pathogens and tackle the crisis brought about by antibiotic-resistant strains. Herein, porous gold nanoparticles (AuPNs) were synthesized as photothermal agents and loaded with indocyanine green (ICG), a common photosensitizer for PDT, to fabricate a nanosystem presenting near-infrared (NIR) light-triggered synchronous PTT and PDT effects. The AuPNs can not only convert NIR light into heat with a high photothermal conversion efficiency (50.6-68.5%), but also provide a porous structure to facilely load ICG molecules. The adsorption of ICG onto AuPNs was mainly driven by electrostatic and hydrophobic interactions with the surfactant layer of AuPNs, and the aggregate state of ICG significantly enhanced its generation of reactive oxygen species. Moreover, taking advantage of its synergistic PTT and PDT effect, the hybrid nanocomposites displayed a remarkable antibacterial effect to the gram-positive pathogen

Near‐infrared photoimmunotherapy (NIR‐PIT) is a new type of cancer treatment, which was recently approved in Japan for patients with inoperable head and neck cancer. NIR‐PIT utilizes antibody‐IRDye700DX (IR700) conjugates and NIR light at a wavelength of 690 nm. NIR light exposure leads to physicochemical changes in the antibody‐IR700 conjugate cell receptor complex, inducing rapid necrotic cell death. Just as fluorescence guided surgery is useful for surgeons to resect tumors completely, real‐time information of tumor locations would help clinicians irradiate NIR light more precisely. IR700 is a fluorescence dye that emits at 702 nm; however, there is no clinically available device optimized for detecting this fluorescence. On the other hand, many indocyanine green (ICG) fluorescence imaging devices have been approved for clinical use. Therefore, we investigated whether LIGHTVISION, one of the clinically available ICG cameras, could be employed for tumor detection. We hypothesized that irradiation with even low‐power 690‐nm laser light, attenuated by 99% with a neutral‐density filter, could be detected with LIGHTVISION without fluorescence decay or therapeutic effect because of the long emission tail of IR700 beyond 800 nm (within the detection range of LIGHTVISION). We demonstrated that the LIGHTVISION camera, originally designed for ICG detection, can detect the tail of IR700 fluorescence in real time, thus enabling the visualization of target tumors., A diagnostic imaging method is developed for accurately localizing tumor and IR700 accumulation based on IR700 fluorescence, using weakened therapeutic laser light at a nontherapeutic dose and a commercially available clinical fluorescence camera for indocyanine green (LIGHTVISION).

The solar spectral converters mainly involve the energy transfer between two codoped ions. Here, we report a series of Ce3+, Cr3+, Ln3+ (Ln = Yb, Nd, Er) tridoped Gd3Sc2Ga3O12 (GSGO) phosphors with improved absorption and increasing near infrared (NIR) emission. We observed the multiple energy transfer behaviors of Cr3+→Ln3+, Ce3+→Ln3+, Ce3+→Cr3+, and Ce3+→Cr3+→Ln3+ in GSGO matrix. When Ce3+ is introduced into the GSGO:Cr3+,Ln3+ phosphors, the energy transfer of Ce3+→Cr3+→Ln3+ has been realized by utilizing the energy transfer bridge of the Cr3+ ion. Consequently, GSGO:Ce3+,Cr3+,Ln3+ can absorb almost all ultraviolet and visible (UV–Vis) light and produce strong NIR light thanks to the synergistic effect of Ce3+→Cr3+→Ln3+, improving the photovoltaic conversion efficiency of c-Si solar cells. Our results show that the prepared GSGO:Ce3+,Cr3+,Ln3+ have the potential application in the solar spectral material for c-Si solar cells. Meanwhile, the strategy of multiple energy transfers gives a new way to design the spectral conversion materials with wider absorption for c-Si solar cells.

Photolabile Protecting Groups (PPGs) are chemical tools used in photopharmacology for the oxygen-independent release of bioactive payloads, enabling spatiotemporal activation of their bioactivity. However, red-shifting of PPG activation wavelengths into the NIR range, light which penetrates the deepest in tissue, has been laborious, and often results in inefficient or insoluble PPGs. This challenge prohibits the use of current photocages in complex biological targets, hindering the progression of photopharmacology into the clinic. To directly address 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 clinically-employed NIR dyes possessing ideal properties, such as NIR-absorption, very high molecular absorptivity, and excellent solubility in aqueous media, can be successfully converted into Cy7-PPG. We report a facile organic synthesis towards Cy7-PPG from easily accessible precursors and confirm its function as an oxygen-independent NIR-PPG. Cy7-PPG is the most redshifted PPG to date (max wavelength = 746 nm), with unmatched molecular absorptivity and solubility, and excellent uncaging efficiency, paving the way for the use of PPGs in the clinic.

Various nanoplatforms have been developed to visualize intracellular microRNAs (miRNAs) because of their clinical significance in tumor progression and diagnosis. However, the diffusion-limited motion of the nanoplatforms penalizes the miRNA imaging efficiency in cells. Herein, we fabricated a near-infrared (NIR) light-propelled Janus-based nanoplatform to advance the imaging response. The Janus nanomotor covered with an Au half-shell was loaded by the endocytosis adjuvant of the MnO2 nanosheet for delivering a miRNA-responsive hQN (hairpin DNA quadrangular nanostructure) probe with a catalyzed hairpin assembly (CHA). Once the nanoplatform entered into cells, the MnO2 nanosheet was degraded to Mn2+ by endogenous fuels (such as glutathione) to release the hQN probe. The NIR light irradiation of the nanoplatform generated a heat gradient and thus propelled motion of the nanoplatform. This process accelerated the intracellular reaction of the hQN probe with miRNAs to trigger the cascade CHA amplification with an enhanced fluorescence readout.

Cancer has become a severe threat to human life due to its high mortality and metastatic rate. Effective inhibition and killing of cancer cells using chemotherapeutic drugs have been a promising means in clinical cancer therapy. However, the low selectivity, drug-resistance, uncontrollability and serious side effects of chemotherapy significantly limit its further development. There is an urgent need for new treatment strategies to compensate for deficiencies inherent in chemotherapy alone. A growing body of research shows that combined treatment strategies have the potential to overcome this dilemma by achieving significantly enhanced synergistic effects and reduced side effects. Emerging phase change materials (PCMs) create an ideal nanoplatform for cancer combination therapy due to their universal loading properties, stable and temperature-responsive phase transition capability, and excellent natural biocompatibility/biodegradability. The release of therapeutic agents can be precisely controlled through external, non-intrusive stimuli (such as NIR light and ultrasound), avoiding systemic toxicity associated with conventional chemotherapy. Herein, the construction methods and design principles of PCM-based nanoplatforms serving as strict gatekeeper and smart payload delivery systems are discussed in detail. Moreover, the advantages and disadvantages of these nanoplatforms are provided. A suitable discussion and perspective of the remaining challenges and future opportunities for PCM-based nanoplatforms in cancer treatment are also given in conclusion.

Near infrared (NIR) light therapy, or photobiomodulation therapy (PBMT), has gained persistent worldwide attention in recent years as a new novel scientific approach for therapeutic applications in ophthalmology. This ongoing therapeutic adoption of NIR therapy is largely propelled by significant advances in the fields of photobiology and bioenergetics, such as the discovery of photoneuromodulation by cytochrome c oxidase and the elucidation of therapeutic biochemical processes. Upon transcranial delivery, NIR light has been shown to significantly increase cytochrome oxidase and superoxide dismutase activities which suggests its role in inducing metabolic and antioxidant beneficial effects. Furthermore, NIR light may also boost cerebral blood flow and cognitive functions in humans without adverse effects. In this review, we highlight the value of NIR therapy as a novel paradigm for treatment of visual and neurological conditions, and provide scientific evidence to support the use of NIR therapy with emphasis on molecular and cellular mechanisms in eye diseases.

Light has been present throughout the history of mankind and even the universe. It is of great significance to human life, contributing to energy, agriculture, communication, and much more. In the biomedical field, light has been developed as a switch to control medical processes with minimal invasion and high spatiotemporal selectivity. During the past three years, near-infrared (NIR) light as long-wavelength light has been applied to more than 3000 achievements in biological applications due to its deep penetration depth and low phototoxicity. Remotely controlled cancer therapy usually involves the conversion of biologically inert NIR light. Thus, various materials, especially nanomaterials that can generate reactive oxygen species (ROS), ultraviolet (UV)/visual light, or thermal energy and so on under NIR illumination achieve great potential for the research of nanomedicine. Here, we offered an overview of recent advances in NIR light-activated nanomedicine for cancer therapeutic applications. NIR-light-conversion nanotechnologies for both directly triggering nanodrugs and smart drug delivery toward tumor therapy were discussed emphatically. The challenges and future trends of the use of NIR light in biomedical applications were also provided as a conclusion. We expect that this review will spark inspiration for biologists, materials scientists, pharmacologists, and chemists to fight against diseases and boost the future clinical-translational applications of NIR technology-based precision nanomedicine.

The gaseous microenvironment (GME) of tumors is rapidly becoming a new concern for nanotechnology-mediated oncotherapy. Here, we constructed a tumor/near-infrared (NIR) light-responsive nanoplatform to generate O2 and NO for remodeling the GME of tumors and phototherapy. The biocompatible and pyrolytic polydopamine was used to load indocyanine green, NONOate, and MnO2 NPs as a nanoenzyme (PINM). Then, HA was modified on the PINM to form the final nanoplatform (PINMH). PINMH can target tumors favorably due to the modification of HA. Under the NIR light irradiation, PINM converts the light and O2 to hyperpyrexia (58.5 °C) and cytotoxic 1O2. MnO2 NPs catalyze the H2O2 overexpressed in tumors to O2, which increases the amount of 1O2. Moreover, NONOate decomposes to NO (100 μM) under hyperpyrexia, thus leading to the gas therapy. The results verified that the responsive nanoplatform with precise gaseous regulation and phototherapy exhibited a superior anti-tumor effect (V/V0 = 1.2) and biosafety. In addition, PINMH can be tracked in real-time via magnetic resonance imaging. In this study, an intelligent nano-platform integrated with diagnosis and treatment was developed, which used the phototherapy technology to reshape GME and achieve good anti-tumor effects, aiming to provide an innovative and reasonable strategy for the development of tumor treatment.

Light-based theranostics have become indispensable tools in the field of cancer nanomedicine. Specifically, near infrared (NIR) light mediated imaging and therapy of deeply seated tumors using a single multi-functional nanoplatform have gained significant attention. To this end, several multi-functional nanomaterials have been utilized to tackle cancer and thereby achieve significant outcomes. The present review mainly focuses on the recent advances in the development of NIR light activatable multi-functional materials such as small molecules, quantum dots, and metallic nanostructures for the diagnosis and treatment of deeply seated tumors. The need for improved disease detection and enhanced treatment options, together with realistic considerations for clinically translatable nanomaterials will be the key driving factors for theranostic agent research in the near future. NIR-light mediated cancer imaging and therapeutic approaches offer several advantages in terms of minimal invasiveness, deeper tissue penetration, spatiotemporal resolution, and molecular specificities. Herein, we have reviewed the recent developments in NIR light responsive multi-functional nanostructures for phototheranostic applications in cancer therapy.

Due to its use of green and renewable energy and negligible bacterial resistance, photocatalytic bacterial inactivation is to be considered a promising sterilization process. Herein, we explore the relevant mechanisms of the photoinduced process on the active sites of semiconductors with an emphasis on the active sites of semiconductors, the photoexcited electron transfer, ROS-induced toxicity and interactions between semiconductors and bacteria. Pristine semiconductors such as metal oxides (TiO2 and ZnO) have been widely reported; however, they suffer some drawbacks such as narrow optical response and high photogenerated carrier recombination. Herein, some typical modification strategies will be discussed including noble metal doping, ion doping, hybrid heterojunctions and dye sensitization. Besides, the biosafety and biocompatibility issues of semiconductor materials are also considered for the evaluation of their potential for further biomedical applications. Furthermore, 2D materials have become promising candidates in recent years due to their wide optical response to NIR light, superior antibacterial activity and favorable biocompatibility. Besides, the current research limitations and challenges are illustrated to introduce the appealing directions and design considerations for the future development of photocatalytic semiconductors for antibacterial applications.

Tumor-targeting gold nanorods (AuNRs) assembled through Au-S bonds have been widely used for photothermal therapy (PTT) via intravenous injection. However, with extended in vivo circulation times, biothiols can replace some S-modified targeting ligands on the surface of the AuNRs, which lowers their targeting efficacy towards cancer cells, resulting in a non-ideal PTT effect. To address this problem, herein, we utilized Se-modified AuNRs to establish a dual functional nanoprobe (Casp-RGD-Se-AuNRs) for improving the therapeutic effect and real-time monitoring of Caspase-9 levels to indicate the degree of cell apoptosis. The experiments demonstrated that the Casp-RGD-Se-AuNRs are better at avoiding interference from biothiols than the S-modified nanoprobe (Casp-RGD-S-AuNRs) for extended blood-circulation times after intravenous injection, significantly improving the PTT efficacy via more effectively targeting cancer cells. Simultaneously, the change of Caspase-9 levels visually shows the degree of apoptosis. Moreover, an in vivo study showed that, compared with the S-modified nanoprobe, the Se-modified nanoprobe exhibits a higher delivery efficiency to the tumor region after intravenous injection (accumulation in the tumor increased by 87%) and a better anticancer efficacy under NIR light irradiation (the tumor inhibition rate increased 6-fold). This work provides a valuable strategy to overcome the off-target problem, and new ideas for avoiding interference by biomolecules during blood circulation.

Using light-harvesting materials to enhance natural photosynthesis is attracting much attention in both materials and plant research. The working efficiency of most light-harvesting materials is, however, compromised by a narrow light-harvesting range (either ultraviolet (UV) only, or near-infrared (NIR) only) and a short lifetime of the excited state. We have now developed a new light-harvesting material (UCNP@CDs) from upconverting nanoparticles (UCNPs) and carbon dots (CDs), which has good photon up- and down-converting properties, because of the UCNPs and CDs, respectively. UCNP@CDs efficiently absorbed and converted both UV and NIR light to visible light, with a long lifetime for the excited state. UCNP@CDs was incorporated into a carboxymethylcellulose (CMC) matrix to produce a light-harvesting film that enhances natural photosynthesis, both by isolated chloroplasts and by living plants. Our rationally designed UCNP@CDs/CMC composite light-harvesting film was able to enhance photosynthesis by Arabidopsis thaliana by ∼12%.

Photoredox catalysis is now considered as a major topic in the field of organic synthesis. Recently, important progress has been made in the development of new processes involving low-energy wavelengths: Near-Infrared (NIR) photoredox catalysis. Shifting from visible to NIR light brings many advantages including mild reaction conditions and deep penetration of light. These benefits will open novel perspectives in organic synthesis. This present review highlights the recent photocatalytic systems that are able to catalyze challenging organic transformations upon NIR activation.

A non-toxic nano system using a cleverly designed dual light can be an important treatment strategy in cancer therapy. Here, we propose a unique concept of synergistic non-toxic nanoplatform, which operates with dual light. An apoferritin nano-platform whose surface was modified with Verteporfin (Visudyne (R)) and with ultra-small CuS nanoparticles in the center demonstrated the synergistic effect of photodynamic therapy (PDT) and photothermal therapy (PTT). The synergistic effect of PDT and PTT were achieved with 808 nm laser light and 690 nm LED light, respectively. These results not only give a new horizon to multifunctional nanostructures for biological applications but also show a new way to design the novel PDT and PTT agents.

Purpose Antibiotic resistance issues associated with microbial pathogenesis are considered to be one of the most serious current threats to health. Fortunately, TiO2, a photoactive semiconductor, was proven to have antibacterial activity and is being widely utilized. However, its use is limited to the short range of absorption wavelength. Methods In this work, heterostructured TiO2-FeS2 nanocomposites (NCs) were successfully prepared by a facile solution approach to enhance light-induced antibacterial activity over a broader absorption range. Results In TiO2-FeS2 NCs, FeS2 NPs, as light harvesters, can effectively increase light absorption from the visible (Vis) to near-infrared (NIR). Results of light-induced antibacterial activities indicated that TiO2-FeS2 NCs had better antibacterial activity than that of only TiO2 nanoparticles (NPs) or only FeS2 NPs. Reactive oxygen species (ROS) measurements also showed that TiO2-FeS2 NCs produced the highest relative ROS levels. Unlike TiO2 NPs, TiO2-FeS2 NCs, under light irradiation with a 515-nm filter, could absorb light wavelengths longer than 515 nm to generate ROS. In the mechanistic study, we found that TiO2 NPs in TiO2-FeS2 NCs could absorb ultraviolet (UV) light to generate photoinduced electrons and holes for ROS generation, including ⋅O2 - and ⋅OH; FeS2 NPs efficiently harvested Vis to NIR light to generate photoinduced electrons, which then were transferred to TiO2 NPs to facilitate ROS generation. Conclusion TiO2-FeS2 NCs with superior light-induced antibacterial activity could be a promising antibacterial agent against bacterial infections.

Ovarian cancer survival and recurrence rate are drastically affected by the amount of tumor that can be surgically removed prior to chemotherapy. Surgeons are currently limited to visual inspection, making smaller tumors difficult to remove surgically. Enhancing the surgeon’s ability to selectively remove cancerous tissue would have a positive effect on a patient’s prognosis. One approach to aid in surgical tumor removal involves using targeted fluorescent probes to selectively label cancerous tissue. To date, there has been a trade off in balancing two requirements for the surgeon: the ability to see maximal tumors and the ability to identify these tumors by eye while performing the surgery. The ability to see maximal tumors has been prioritized and this has led to the use of fluorophores activated by near-infrared (NIR) light as NIR penetrates most deeply in this surgical setting, but the light emitted by traditional NIR fluorophores is invisible to the naked eye. This has necessitated the use of specialty detectors and monitors that the surgeon must consult while performing the surgery. In this study, we develop nanoparticles that selectively label ovarian tumors and are activated by NIR light but emit visible light. This potentially allows for maximal tumor observation and real time detection by eye during surgery. We designed two generations of up-converting nanoparticles (UCNPs) that emit green light when illuminated with NIR light. These particles specifically label ovarian tumors most likely via tumor-associated macrophages (TAMs), which are prominent in the tumor microenvironment. Our results demonstrate that this approach is viable means of visualizing tumors during surgery without the need for complicated, expensive, and bulky detection equipment. Continued improvement and experimentation could expand our approach into a much needed surgical technique to aid ovarian tumor removal.

Bacterial infections are becoming a serious public health challenge because the abuse of antibiotics worldwide has caused bacterial resistance and the occurrence of superbugs. In this work, a new near-infrared (NIR) photoresponsive coating was constructed on Ti implant material, which was composed of MnO2, IR780 photosensitizer and polydopamine (PDA). Under the irradiation of 808 nm NIR light, the component of MnO2 in the coating exhibited high photothermal performance, and IR780 could be stimulated to generate ROS as a photosensitizer. The addition of PDA not only improved the cytocompatibility of the composite coating but also strengthened the light absorption ability of the system. Under the irradiation of 808 nm NIR light for 15 min, the composite coating killed 99.94% Staphylococcus aureus and 99.89% Escherichia coli on Ti plates. This rapid and highly effective bactericidal rate was ascribed to the synergistic effects of photothermal performance and photodynamic effect of the coatings excited by NIR light. Cell culture tests showed that PDA/IR780@MnO2–Ti had good cytocompatibility due to the excellent biocompatibility of PDA and nanostructured surface. Therefore, this surface system will be a very promising plateform to safely and effectively kill bacteria on biomedical devices and implants in a short time.