1O2 Production Research Articles

Synthesis and Catalytic Property of Ribonucleoside-Derived Carbon Dots.

Exploring appropriate precursors has been proposed to be a promising strategy for the creation of artificial enzymes that are emerging as alternatives of natural enzymes. Herein, inspired by the catalytic activities of ribose nucleic acid, using ribonucleosides as precursors including adenosine, guanosine, cytidine, and uridine, respectively, four carbonic aggregates, namely, carbon dots (A-CDs, G-CDs, C-CDs, and U-CDs) to mimic artificial enzymes are synthesized. All the CDs show a planar graphene-like structure and thus can intercalatively bind with DNA double helix. Different from the other three CDs, the uridine-derived U-CDs exhibit unique catalytic property, which can mediate the topological transformation of DNA from supercoiled to nicked open-circular conformation. U-CDs can catalyze oxidation of O2 to generate singlet oxygen 1 O2 via a Haber-Weiss reaction, and consequently mediate oxidative cleavage of phosphate backbone in DNA and release the torsional energy stored in supercoiled DNA. Explorations reveal that the unique highly active oxygenated species, namely, quinone groups that are on the edge of U-CDs, play a key role in the catalytic production of 1 O2 . This work represents a new insight that using natural biomolecules in living systems as precursors can create new species beyond life.

An Effective Supramolecular Approach to Boost the Photodynamic Therapy Efficacy of a Near-Infrared Activating Perylene Diimide-Based Photosensitizer

Perylene diimide (PDI) derivatives with outstanding photo-physicochemical properties hold significant promise for application in solar energy conversion, pollutant degradation, and disease diagnosis. However, the inherent characteristics of PDI molecules, including poor water solubility, short-wavelength absorption, and negligible singlet oxygen (1O2) generation capabilities, severely limit their application in photodynamic therapy (PDT). Here, a novel PDI-based photosensitizer was deliberately designed with the potential to solve these limitations. By facile modifications of a PDI molecule, we constructed an amphiphilic PDI-based compound (PDIPa) that can be self-assembled into a functional supramolecular photosensitizer (NanoPDIPa) with excellent water dispersity and intense near-infrared (NIR) absorbance. Remarkably, the intermolecular electronic coupling and interaction in NanoPDIPa can induce efficiency intersystem crossing (ISC) through the minimization of singlet–triplet energy gap (ΔEST), a characteristic that is not possessed by the monomer, thus resulting in significant 1O2 production. The successful development of NanoPDIPa not only can enlarge the family of NIR-absorbing photosensitizers for potential PDT applications but also can provide a solution to overcome the limitations of clinically used photosensitizers.

Hematoporphyrin monomethyl ether mediated photodynamic therapy inhibits oral squamous cell carcinoma by regulating the P53-miR-21-PDCD4 axis via singlet oxygen.

The objective of this study was to determine the mechanism and effect of hematoporphyrin monomethyl ether mediated photodynamic therapy (HMME-PDT) on oral squamous cell carcinoma (OSCC). Human OSCC CAL-27 cells were randomly divided into four groups: control group, HMME group, laser group, and HMME-PDT group. Cell viability was detected by the CCK-8 method. Cell cycle distribution was evaluated by flow cytometry. GEO database was used to screen differentially expressed microRNAs (DEMs), and TCGA database was performed to verify DEM expression in OSCC and normal tissues. The effects of HMME-PDT on DEM expression were assayed by real-time PCR, and the expressions of miRNAs target genes were measured by western blot. Fluorescence probes were used to determine the production of singlet oxygen (1O2). Compared with the other three groups, HMME-PDT dramatically inhibited CAL-27 cell proliferation and induced G0/G1 cycle arrest. The expressions of miR-21 and miR-155 were significantly upregulated in OSCC. HMME-PDT downregulated the expression of miR-21 but had no obvious effect on miR-155. HMME-PDT remarkably upregulated the levels of P53 and miR-21 target proteins, such as PDCD4, RECK, and SPRY2. 1O2 was generated during HMME-PDT, and inhibition of 1O2 production could reverse the regulation of HMME-PDT on P53, miR-21, and its target proteins, thus restoring cell viability. HMME-PDT can significantly inhibit the growth of OSCC cells, and the mechanism of this effect is related to the regulation of the P53-miR-21-PDCD4 axis via 1O2 induced by HMME-PDT.

Boosting reactive oxygen species generation over Bi3O4Br/CuBi2O4 by activating peroxymonosulfate under visible light irradiation

Given the limitations of conventional advanced oxidation processes (AOPs), a coupling system by integrating sulfate radical-based AOPs (SO4--AOPs) with photocatalysis for boosting the peroxymonosulfate (PMS) activation under visible light was established. Herein, we developed a novel 5 %Bi3O4Br/CuBi2O4 catalyst for rapid and efficient degradation of tetracycline (TC). The rate constant (k) for degrading TC in 5 %Bi3O4Br/CuBi2O4 + PMS + Vis system was 3.69 min−1, which is 30.62, 2.18 times higher than that of photocatalysis and SO4--AOPs alone, respectively. The quenching experiments verified that h+, OH, O2– and 1O2 were dominant contributors for the degradation of TC. EPR and quantitative analysis further implied illumination was favor in achieving mass production of OH and 1O2. Moreover, O2– and SO4- might convert into 1O2 in the 5 %Bi3O4Br/CuBi2O4 + PMS + Vis system. The degradation pathways of TC were proposed and the toxicity of intermediates was much lower than that of untreated TC. Besides, the 5 %Bi3O4Br/CuBi2O4 + PMS + Vis system showed over 90% removal rate in a wide pH range (3–11) or different concentrations of inorganic anions. This work provided a worthy reference in developing an environmentally-friendly system for the high-efficiency degradation of antibiotics.

Dual-functionalized luminescent/photodynamic composite fabrics: Synergistic antibacterial activity for self-disinfecting textiles

For the purpose of developing self-disinfecting photodynamic textiles with enhanced antibacterial activity, here we report a scalable and facile method to immobilize the long persistent phosphor SrAl2O4:Eu2+, Dy3+ (SAOED) and the photosensitizer Rose Bengal onto cotton fabric (CF) by knife coating and photocrosslinking methods. The resultant composite material, termed SAOED/RB-CF, exhibited superior synergistic antibacterial efficacy capable of 99.999% (5 log units, detection limit) and 99.986% (3.9 log units) photoinactivation against Staphylococcus aureus and methicillin-resistant S. aureus (MRSA), respectively, under visible-light illumination (Xenon lamp). Mechanistic studies employing both substrate photooxidation and EPR spin-trapping methods demonstrated an enhanced yield of singlet oxygen (1O2) production compared to the RB/CF material alone (without the phosphor), suggesting that the light emitted from the phosphorescence of the photoexcited SAOED could be absorbed by the RB photosensitizer under dark conditions, resulting in effective synergistic pathogen inactivation. In addition, the SAOED/RB-CF composite fabric possessed excellent abrasion resistance, mechanical strength and color fastness. Our findings suggest that the integration of long persistent phosphors into photodynamic materials may provide a new avenue to explore for developing composite fabrics as applied materials in infection control applications for use in both healthcare environments and consumer textiles.

Enhanced ciprofloxacin degradation by electrochemical activation of persulfate using iron decorated carbon membrane cathode: Promoting direct single electron transfer to produce 1O2

In this work, electrochemical activation of persulfate (E-PS) for the energy efficient treatment of ciprofloxacin (CIP) was performed using a novel iron-decorated carbon membrane (FeCM) cathode and SnO2-Bi/Ti anode. Synergistic effect of electrochemical oxidation and PS activation resulted in superior CIP removal. The FeCM cathode outperforms various cathodes (Pt, Ti, graphite, and stainless steel), owing to the existence of C = O, Fe2+/Fe3+, and F on FeCM, which can facilitate 1O2 generation and utilization in the E-PS system. Moreover, the continuous supply of negative charges endows rapid redox cycle of Fe2+/Fe3+ on FeCM cathode, which not only prevents iron leaching, but also reduces the consumption of active sites, and thus, enables FeCM with high stability over a wide pH range and improved cyclic performance. The potential of E-FeCM-PS for outdoor application were evaluated by removing various persistent organic pollutants, and treating actual hospital effluent. The CIP removal mechanism in the E-FeCM-PS process and the possible CIP degradation pathways were proposed. Overall, this work provides a plausible route for the continuous production of 1O2 for effective abatement of organic contaminants via electro-activation of PS and gives an insight into the intrinsic role of iron-doped carbon membrane for persulfate cathodic activation.

Bimetallic PdPt-based nanocatalysts for Photothermal-Augmented tumor starvation and sonodynamic therapy in NIR-II biowindow assisted by an oxygen Self-Supply strategy

Tumor starvation by depleting intratumoral glucose has been validated as a promising therapeutic strategy to combat cancer. However, inadequate oxygenation in hypoxic tumorous tissue significantly compromises the treatment efficacy. Herein, PdPt bimetallic nanocatalyst conjugated with glucose oxidase (GOx) and sonosensitizer IR780 is developed for photothermal-augmented tumor starvation and sonodynamic therapy (SDT) in near-infrared (NIR)-II biowindow, assisted by an oxygen self-supply strategy. As a catalase-mimicking nanozyme, PdPt@GOx/IR780 (PGI) can facilitate the alleviation of tumor hypoxia through catalyzing H2O2 decomposition into O2. Furthermore, GOx-mediated intratumoral glucose consumption may block the essential energy and nutrient supply to achieve tumor starvation. The resultant H2O2 production enables a continuous supply of local O2, which subsequently aggravates glucose depletion. Meanwhile, the hypoxia alleviation also promotes the production of 1O2 for a more efficacious SDT with the aid of sonosensitizer IR780. In another aspect, hyperthermia generation by PGI under NIR-II laser irradiation leads to the thermal ablation of tumor cells, which effectively incorporates with tumor starvation and SDT for a complete tumor eradication. More importantly, the combination therapy can trigger strong immunogenic cell death (ICD), which favors the overcoming of immune suppression and the enhancement of antitumor immunity. The admirable tumor suppression effect by PGI is demonstrated on tumor-bearing mice with minimal adverse effect. Taken together, this paradigm provides a useful strategy for PdPt functionalization in the pursuit of effective tumor therapy with high clinical relevance.

Engineering Cu-CuFe2O4 nanoenzyme for hypoxia-relief and GSH-depletion enhanced chemodynamic/sonodynamic therapy

Specific hypoxia and overexpressed glutathione (GSH) in the tumor microenvironment (TME) are bottleneck for reactive oxygen species (ROS)-involved therapy performance. Herein, we report a novel Cu-CuFe2O4 nanoenzyme enables simultaneous hypoxia relief and GSH depletion for efficiently augmenting ROS-involved chemodynamic (CDT)/sonodynamic (SDT) therapy. The nanoenzyme exhibited both catalase-like and GSH peroxidase-like catalytic activities, which can persistently catalyze tumor-overexpressed hydrogen peroxide (H2O2) to generate oxygen (O2) to facilitate singlet oxygen (1O2) production under an external ultrasound, achieving hypoxia-relieved SDT. Meanwhile, the Cu-CuFe2O4 NPs reacted with GSH to deplete GSH and release Fenton-like Cu+ and Fe2+ ions to mediate abundant hydroxyl radical (OH) production for CDT. Highly efficient anticancer ability of the Cu-CuFe2O4 NPs was demonstrated from the efficient MCF-7 cells killing and multicellular tumor spheroids (MCTS) elimination. This work provides a useful strategy to design multi-mode TME-responsive nanosonosensitizer for enhancing therapeutic effect of cancer therapy via persistent and simultaneous regulatory of TME, showing a great potential for clinical cancer therapy.

In-situ production of singlet oxygen by dioxygen activation on iron phosphide for advanced oxidation processes

In this study, we delicately design a novel iron-based dioxygen activation system for sustainable production of 1O2 on iron phosphide (FeP). This is the first time to realize the 1O2 production on Fe-based dioxygen activation. Unlike traditional iron-based materials that only activate dioxygen, this delicately designed FeP can simultaneously activate dioxygen and adsorb some generated •OH. Those •OH can react with O2•−/HO2•. Thus, the •OH-mediated reaction can in-situ occur on the surface of FeP to rapidly produce 1O2. As a result, the FeP exhibits remarkably higher degradation activity for various organic pollutants and pollutants in real aquatic systems in absence of light, electricity and other oxidants. Therefore, this study provides a green strategy to generate 1O2 for environmental remediation and also demonstrates a new role of surface-bound •OH in contributing to the 1O2 production.

A Photosensitized Singlet Oxygen (1O2) Toolbox for Bio-Organic Applications: Tailoring 1O2 Generation for DNA and Protein Labelling, Targeting and Biosensing.

Singlet oxygen (1O2) is the excited state of ground, triplet state, molecular oxygen (O2). Photosensitized 1O2 has been extensively studied as one of the reactive oxygen species (ROS), responsible for damage of cellular components (protein, DNA, lipids). On the other hand, its generation has been exploited in organic synthesis, as well as in photodynamic therapy for the treatment of various forms of cancer. The aim of this review is to highlight the versatility of 1O2, discussing the main bioorganic applications reported over the past decades, which rely on its production. After a brief introduction on the photosensitized production of 1O2, we will describe the main aspects involving the biologically relevant damage that can accompany an uncontrolled, aspecific generation of this ROS. We then discuss in more detail a series of biological applications featuring 1O2 generation, including protein and DNA labelling, cross-linking and biosensing. Finally, we will highlight the methodologies available to tailor 1O2 generation, in order to accomplish the proposed bioorganic transformations while avoiding, at the same time, collateral damage related to an untamed production of this reactive species.

Engineering single-atom Fe-Pyridine N4 sites to boost peroxymonosulfate activation for antibiotic degradation in a wide pH range

Single-atom Fe catalysts have shown great potential for Fenton-like technology in organic pollutant decomposition. However, the underlying reaction pathway and the identification of Fe active sites capable of activating peroxymonosulfate (PMS) across a wide pH range remain unknown. We presented a novel strategy for deciphering the production of singlet oxygen (1O2) by regulating the Fe active sites in this study. Fe single atoms loaded on nitrogen-doped porous carbon (FeSA-CN) catalysts were synthesized using a cage encapsulation method and compared to Fe-nanoparticle-loaded catalysts. It was discovered that FeSA-CN catalysts served as efficient PMS activators for pollutant decomposition over a wide pH range. Several analytical measurements and density functional theory calculations revealed that the pyridinic N-ligated Fe single atom (Fe-pyridine N4) was involved in the production of 1O2 by the binding of two PMS ions, resulting in an excellent catalytic performance for PMS adsorption/activation. This work has the potential to not only improve the understanding of nonradical reaction pathway but to also provide a generalizable method for producing highly stable PMS activators with high activity for practical wastewater treatment.

Aggregation Turns BODIPY Fluorophores into Photosensitizers: Reversibly Switching Intersystem Crossing On and Off for Smart Photodynamic Therapy

Aggregation Turns BODIPY Fluorophores into Photosensitizers: Reversibly Switching Intersystem Crossing On and Off for Smart Photodynamic Therapy

Tumor microenvironment-responsive MnSiO3-Pt@BSA-Ce6 nanoplatform for synergistic catalysis-enhanced sonodynamic and chemodynamic cancer therapy

Compared with traditional photodynamic therapy (PDT), ultrasound (US) triggered sonodynamic therapy (SDT) has a wide application prospect in tumor therapy because of its deeper penetration depth. Herein, a novel MnSiO3-Pt (MP) nanocomposite composed of MnSiO3 nanosphere and noble metallic Pt was successfully constructed. After modification with bovine serum albumin (BSA) and chlorine e6 (Ce6), the multifunctional nanoplatform MnSiO3-Pt@BSA-Ce6 (MPBC) realized the magnetic resonance imaging (MRI)-guided synergetic SDT/chemodynamic therapy (CDT). In this nanoplatform, sonosensitizer Ce6 can generate singlet oxygen (1O2) to kill cancer cells under US irradiation. Meanwhile, the loaded Pt has the ability to catalyze the decomposition of overexpressed hydrogen peroxide (H2O2) in tumor microenvironment (TME) to produce oxygen (O2), which can conquer tumor hypoxia and promote the SDT-induced 1O2 production. In addition, MP can degrade in mildly acidic and reductive TME, causing the release of Mn2+. The released Mn2+ not only can be used for MRI, but also can generate hydroxyl radical (∙OH) for CDT by Fenton-like reaction. The multifunctional nanoplatform MPBC has high biological safety and good anticancer effect, which displays the great latent capacity in biological application.

AIE-based gold nanostar-berberine dimer nanocomposites for PDT and PTT combination therapy toward breast cancer.

We designed and synthesized three new berberine-based compounds, namely, pyridine-2,6-dimethyl-/2,2'-bipyridine-3,3'-dimethyl-tethered berberine dimers BD1 and BD2, and a tetrakis(4-benzyl)ethylene linked berberine tetramer BD4. We identified that the dimer BD2 and tetramer BD4, as well as 1,10-phenanthroline-2,9-dimethyl-linked berberine dimer BD3 previously reported by us, showed remarkable aggregation-induced emission (AIE) properties which endowed them with higher singlet oxygen (1O2) production ability than berberine. Of the four compounds, BD3 exhibits the lowest ΔEST energy with the highest 1O2 generation ability and thus was selected for further construction of AuNSs-BD3@HA (denoted as ABH, AuNSs = gold nanostars; HA = hyaluronic acid). The nanosystem of ABH shows a remarkable therapeutic effect toward breast cancer by combining photodynamic therapy (PDT) from BD3, photothermal therapy (PTT) from AuNSs, and the CD44-targeting capability of HA. The synergistically enhanced PDT and PTT induce superior cancer cell apoptosis/necrosis in vitro and anti-breast cancer activity in vivo. This study provides a new concept for PDT using natural product derivatives and their combination with PTT for efficient treatment of tumors.

MOF-coated upconversion nanoconstructs for synergetic photo-chemodynamic/oxygen-elevated photodynamic therapy.

Excessive production of intracellular reactive oxygen species (ROS) can induce apoptosis of cancer cells; however, it is often limited by severe triggering conditions and hypoxic microenvironments of solid tumors. To address these issues, herein, we have designed a MOF-coated upconversion nanoconstruct (UCTSCF, referring to UC@Ce6/TFS@mSiO2@MIL-100(Cu/Fe)) for synergetic photochemodynamic therapy (PCT)/oxygen-elevated photodynamic therapy (PDT). The MOF (MIL-100(Fe)) coating with Cu-doping was designed to catalyze H2O2 overexpression in cancer cells to generate the most cytotoxic ˙OH via chemodynamic therapy (CDT). It is noted that UC, representing 808 nm driven upconversion nanoparticles with high tissue penetration depth/low over-heating effects, was designed to provide intense blue light which can relieve the severe triggering conditions of CDT via PCT. Furthermore, the functional layer of the photosensitizer chlorin e6 (Ce6) and O2-carrying triethoxy(1H,1H,2H,2H-nonafluorohexyl)silane (TFS) co-doped mesoporous silicon (Ce6/TFS@mSiO2) can cause oxygen-elevated 1O2 production upon 671 nm light irradiation. In such a simple ROS generation nanoplatform, we heighten the antitumor effect via oxygen-elevated synergetic tumor PCT/PDT.

Boosting the singlet oxygen production from H2O2 activation with highly dispersed Co-N-graphene for pollutant removal.

Singlet oxygen (1O2) is a promising reactive species for the selective degradation of organic pollutants. However, it is difficult to generate 1O2 from H2O2 activation with high efficiency and selectivity. In this work, a graphene-supported highly dispersed cobalt catalyst with abundant Co–Nx active sites (Co–N-graphene) was synthesized for activating H2O2. The Co–N-graphene catalyzed H2O2 reaction system selectively catalyzed 1O2 production associated with the superoxide radical (O2˙−) as the critical intermediate, as proven by scavenger experiments, electron spin resonance (ESR) spin trapping and a kinetic solvent isotope effect study. This resulted in excellent degradation efficiency towards the model organic pollutant methylene blue (MB), with an outstanding pseudo-first-order kinetic rate constant of 0.432 min−1 (g Lcatalyst−1)−1 under optimal reaction conditions (CH2O2 = 400 mM, initial pH = 9). Furthermore, this Co–N-graphene catalyst enabled strong synergy with HCO3− in accelerating MB degradation, whereas the scavenger experiment implied that the synergy herein differed significantly from the current Co2+–HCO3− reaction system, in which contribution of O2˙− was only validated with a Co–N-graphene catalyst. Therefore, this work developed a novel catalyst for boosting 1O2 production from H2O2 activation and will extend the inventory of catalysts for advanced oxidation processes.

Enhancing Intersystem Crossing by Intermolecular Dimer-Stacking of Cyanine as Photosensitizer for Cancer Therapy

Enhancing Intersystem Crossing by Intermolecular Dimer-Stacking of Cyanine as Photosensitizer for Cancer Therapy

Microfluidic Synthesis of Theranostic Nanoparticles with Near-Infrared Scintillation: Toward Next-Generation Dosimetry in X-ray-Induced Photodynamic Therapy.

We developed a microfluidic synthesis to grow GdF3:Eu theranostic scintillating nanoparticles to simultaneously monitor the X-ray dose delivered to tumors during treatments with X-ray activated photodynamic therapy (X-PDT). The flow reaction was optimized to enhance scintillation emission from the Eu3+ ions. The as-prepared ∼15 nm rhombohedral-shaped nanoparticles self-assembled into ∼100 nm mesoporous flower-like nanostructures, but the rhombohedral units remained intact and the scintillation spectra unaltered. The conjugation of the ScNPs with multilayers of methylene blue (MB) in a core-shell structure (GdF@MB) resulted in enhanced singlet oxygen (1O2) generation under X-ray irradiation, with maximum 1O2 production for nanoparticles with 4 MB layers (GdF@4MB). High 1O2 yield was further evidenced in cytotoxicity assays, demonstrating complete cell death only for the association of ScNPs with MB and X-rays. Because the scintillating Eu3+ emission at 694 nm is within the therapeutic window and was only partially absorbed by the MB molecules, it was explored for getting in vivo dosimetric information. Using porcine skin and fat to simulate the optical and radiological properties of the human tissues, we showed that the scintillation light can be detected for a tissue layer of ∼16 mm, thick enough to be employed in radiotherapy treatments of breast cancers, for instance. Therefore, the GdF3:Eu ScNPs and the GdF@4MB nanoconjugates are strong candidates for treating cancer with X-PDT while monitoring the treatment and the radiation dose delivered, opening new avenues to develop a next-generation modality of real-time in vivo dosimetry.

Singlet oxygen-dominated activation of peroxymonosulfate by CuO/MXene nanocomposites for efficient decontamination of carbamazepine under high salinity conditions: Performance and singlet oxygen evolution mechanism

The degradation of organic contaminants via traditional radical-dominated advanced oxidation processes (AOPs) under high salinity conditions was limited due to side reactions between coexisting inorganic anions and radicals. Herein, a nonradical oxidation process via peroxymonosulfate (PMS) activation by CuO/MXene for treating high-salinity organic wastewater was developed. Rapid removal efficiency of target pollutant carbamazepine (CBZ) was significantly enhanced to 95.88% within 20 min by CuO/MXene under high salinity conditions (NaCl, 200 mM), compared to the efficiency of 4.30% exhibited by PMS alone. Besides, CBZ maintained a higher removal efficiency of > 81.04% in complex highly saline wastewater composed of eight common inorganic anions. Radical quenching experiments and electron paramagnetic resonance (EPR) analysis confirmed that radical and nonradical oxidation processes were involved in the catalytic process. However, singlet oxygen (1O2) was identified as the primary reactive species, and its contribution rate to CBZ degradation was > 73.58% in a wide pH range (3.0-9.0). The oxygenated functional groups and the interaction between CuO/MXene and PMS facilitated the production of 1O2. The degradation pathway was proposed based on the detection of intermediates. This work provided a new inspiration for the decontamination of organic contaminants under high salinity conditions via a nonradical oxidation process.

Near-infrared vinyl-containing aza-BODIPY nanoparticles as photosensitizer for phototherapy

Novel vinyl-containing pyrroles were developed by the reaction of vinyl-containing ketones with 3-phenyl-2H-azirine in the presence of LDA. Utilizing these pyrroles, asymmetric vinyl-containing azaBDPs 1–8 were prepared, avoiding to the use of Knoevenagel condensation. Solid-state structure of 7 was confirmed by X-ray crystallographic analysis, and the furan, the vinyl group and the pyrrole segment in 7 are almost coplanar, owing to the conjugation. AzaBDPs 1–8 absorb and emit beyond 685 nm, and have low fluorescence quantum yields. AzaBDPs 1–8 were found to merely possess the 1O2 production capacity. The formed azaBDP nanoparticles (7-NPs) by facile encapsulation of F127 exhibit the excellent photothermal stabilities. Noteworthily, 7-NPs show the outstanding photothermal conversion efficiency (η = 55%) in aza-BODIPY system, and can effectively kill cancer cells through the photothermal conversion, which is highly desirable for an effective and potential tumor phototherapeutic reagent.