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The disintegration of nanoparticles and drug release are important and imperative for nanoparticle formulations of therapeutic agents. However, quantitatively monitoring the drug release of nanomedicines is a major challenge. In this work, boron-dipyrromethene (BDP) was applied as a model drug to study the disassembly of nanoparticles and drug release. BDP dimers with disulfide and ester bonds were synthesized, and their nanoparticles were made. The accurate analysis of bond breaking in BDP nanoparticles could not be realized by using confocal laser scanning microscopy. Hence, the possible products after bond cleavage were quantified by using liquid chromatography tandem mass spectrometry (LC-MS/MS). BDP nanoparticles could be endocytosed into cancer cells, and the disulfide bonds and ester bonds were broken to promote the disassociation of nanoparticles and BDP release. Then, near-infrared BDP nanoparticles were investigated in live mice by near-infrared fluorescence imaging and LC-MS/MS. The release of BDP was low (<10%) and BDP maintained the original dimer structure in vivo , which showed that the bond breaking for BDP nanoparticles was difficult in vivo . These results could help us understand the breaking law of disulfide bonds and ester bonds in nanoparticles and are beneficial for developing practical new drug formulations.

Lung cancer is the major cause of cancer death worldwide. Immune checkpoint inhibitors (ICIs) of PD-1/PD-L1 have improved the survival rate in some patients with lung cancer. However, the efficacy of ICIs is limited by the inhibitory tumor immune microenvironment. Herein, we designed porphyrin cholesterol conjugates (TPPC) for synergistic photodynamic therapy (PDT)-immunotherapy for lung cancer. Porphyrin derivatives with great reactive oxygen species (ROS) production efficiency have been applied as photosensitizers in clinics, and cholesterol is one of the main components of the cell membrane. Porphyrin cholesterol conjugates could assemble into nanoparticles (NPs) in the absence of surfactants or amphiphilic polymers. On the other hand, TPPC NP-mediated PDT could accumulate at the tumor site and induce immunogenic cell death to stimulate and recruit antigen-presenting cells to mature and activate T cells, rendering cancer cells more sensitive to ICIs. Importantly, the combination strategy reshapes the tumor immune microenvironment to enhance the antitumor immune response and significantly suppresses the tumor growth and eliminates metastasis. This study offers theoretical guidance for the combination of PDT and ICIs as a potential therapeutic option in lung cancer.

Amino acids are one kind of basic life unit in biological systems. Modification with amino acids may bring interesting properties to the principal molecules. In this work, BDP was modified with L-aspartic acid (Asp) and D-Asp to obtain BDP-LAsp and BDP-DAsp, respectively. The as-synthesized BDPs can self-assemble into uniform nanoparticles (NPs) due to the hydrophilicity of Asp. We found that BDP-LAsp NPs possessed higher photodynamic therapeutic efficacy than BDP-DAsp NPs in fighting against cancer cells and bacteria. This provides a simple design strategy for the modification of photosensitizers in the biomedical field.

Charge-transfer assemblies (CTAs) represent a new class of functional material due to their excellent optical properties, and show great promise in the biomedical field. Porphyrins are widely used photosensitizers, but the short absorption wavelengths may restrict their practical applications. To obtain porphyrin phototherapeutic agents with red-shifted absorption, charge-transfer nanoscale assemblies (TAPP-TCNQ NPs) of 5,10,15,20-tetrakis(4-aminophenyl) porphyrin (TAPP) and 7,7,8,8‑tetracyanoquinodimethane (TCNQ) were prepared via optimizing the stoichiometric ratios of donor-acceptor. The as-prepared TAPP-TCNQ NPs exhibit red-shifted absorption to the near-infrared (NIR) region and enhanced absorbance because of the charge-transfer interactions. In especial, TAPP-TCNQ NPs possess the capacity of both photodynamic and photothermal therapy, thus effectively killing the bacteria upon 808 nm laser irradiation. This modular assembly method provides an alternative strategy to enhance the application of the phototherapeutic agents., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The combination of gene therapy and chemotherapy is emerging as a promising strategy for multidrug-resistant (MDR) cancer treatment. However, due to the significant differences in the physicochemical properties between macromolecular oligonucleotides and chemodrugs, the co-delivery of different drug combos makes for a great challenge. Moreover, the biosafety of the carriers and poor lysosomal escape of oligonucleotides are the main concerns for combination therapy. Herein, we developed a facile carrier-free strategy to co-deliver small interfering RNA (siRNA) and positive-charged chemodrugs (termed cationic amphiphilic chemodrugs, CACDs), in which CACDs interact with negative-charged anti P-glycoprotein siRNA (siPgp) without extra carriers and self-assemble into siPgp/CACDs nanoparticles (NPs [siPgp/CACDs] ). Meanwhile, the CACDs also play an important role in the lysosomal escape of siRNA. Both molecular dynamics simulations and experimental characterization demonstrate that CACDs and siRNA can self-assemble into nanoparticles. Furthermore, red blood cell membrane (RBCm) was used to camouflage the NPs [siPgp/CACDs] to enhance their physiological stability and prolong the circulation time. Both in vitro and in vivo assessments reveal their excellent performance for drug-resistant cancer treatment. This strategy provides a safe and efficient pathway for gene and chemo combination therapy for MDR cancers.

P-glycoprotein (P-gp) induced multidrug resistance (MDR) is the main reason for the failure of cancer chemotherapy. The combined delivery of chemodrug and P-gp inhibitor is a promising pathway to reverse MDR. However, the intrinsic stimuli in the tumor microenvironment could not realize a complete drug release, which would induce poor cancer therapeutic efficacy. Herein, we conjugated tamoxifen (TAM) with D-α-tocopherol polyethylene glycol1000 succinate (TPGS) based on a reactive oxygen species (ROS)-responsive aryl boronic ester bond to construct a self-amplified ROS-responsive chemodrug-inhibitor (TPGS-TAM) co-delivery system. Due to its amphiphilic property, the TPGS-TAM conjugates could self-assemble into uniform spherical nanoparticles (NPs). After effective endocytosis by cancer cells, the intracellular ROS cleaved the aryl boronic ester bond and initiated the release of TAM and α-tocopherol succinate (α-TOS) from the NPs. Subsequently, the released α-TOS further generated ROS to facilitate the release of TAM. Moreover, α-TOS also consumed adenosine triphosphate (ATP) to impair ATP-dependent P-gp mediated drug efflux to reverse the tumor's drug resistance. As a result, the TPGS-TAM NPs enhanced the antitumor effect with a tumor inhibition rate (TIR) high up to 74.6 ± 6.1% in an MCF-7/ADR tumor model. Based on systematic in vitro and in vivo assessments, this self-amplified ROS-responsive carrier-free conjugate of chemodrug/P-gp inhibitor may shed light on the potential application for the MDR cancer therapy.

Copper-based nanomaterials are widely used in near-infrared (NIR) light-mediated deep tumor treatment because of their abundant photothermal and photodynamic properties. However, copper phosphide (Cu 3 P) nanoparticles (NPs) are rarely investigated. Herein, Cu 3 P NPs were prepared to strengthen their local surface plasmon resonance absorption in the NIR region, exhibiting promising photothermal and photodynamic properties. After surface modification by polyethylene glycol, the formed p Cu 3 P NPs showed negligible influence on the viability of 4T1 cells, presenting remarkable biocompatibility. However, with 808 nm irradiation, p Cu 3 P NPs could induce HSP70 and HO-1 protein expression and enhance intracellular reactive oxygen species levels, leading to dramatic cell death. In 4T1 tumor-bearing mice, an intravenous injection of biocompatible p Cu 3 P NP could lead to remarkable aggregation in the tumor region and significantly inhibit tumor growth under 808 nm laser irradiation, presenting great potential for tumor therapy.

Fluorescence imaging is a non-invasive imaging technique, which facilitates the visualization of sub-cellular components in cells with high sensitivity and selectivity. Up to now, only indocyanine green (ICG) has been approved as a diagnostic reagent for intravenous application. But the intrinsic disadvantage of ICG has spurred more research attention to exploit new fluorescent materials in imaging fields. In the last decade, many materials, including inorganic and organic materials, have been developed for fluorescence imaging. There are some reviews about fluorescence bioimaging. In this review, we will summarize and highlight the reported organic nanoparticles for noninvasive long-term bioimaging. According to the emitting mechanism, fluorescent nanoparticles obtained from fluorophores with aggregation-caused quenching and aggregation-induced emission features are discussed respectively. Finally, we come up with some key issues and challenges in the future and clinical translation.

Liver tumor is one of the most lethal cancers due to its low ratio of surgical resection, high recurrence rate, and invasiveness. Photothermal therapy (PTT) possesses many advantages for cancer therapy because of its noninvasive nature. However, most PTT is conducted in the first near-infrared (NIR-I) window, so second near-infrared (NIR-II) photosensitizers with higher penetrating ability and clinical prospects are seriously desirable. Herein, a semiconducting polymer with optimized absorption in NIR-I and NIR-II regions is obtained by ternary copolymerization methodology. The prepared nanoparticle (NP) from the semiconducting polymer is used for treatment of orthotopic liver cancer upon laser irradiation. Compared with an 808 nm laser, a 1064 nm laser leads to more effective inhibition toward orthotopic liver cancer in the same conditions. These results thus demonstrate that the NIR-II polymeric NPs may inspire another aspect for highly efficient therapy of various orthotopic cancers.

Application of organic dyes is limited in biomedical fields due to the rapid self-quenching, poor stability and water solubility. In this work, polymer modified organic dyes is developed through the dyes initiating polymerization. The polymer length is studied by tuning the amount of monomer. With an optimal molecule weight of the polymer, the π-π stacking from π-conjugated organic fluorescent dyes and fluorescence quenching are inhibited, resulting in an enhancement of fluorescence intensity and photostability. Nanoparticles are further fabricated to be used for cell uptake based on the optimized organic dyes. Then, long term cellular fluorescence imaging is realized. This work highlights the potential of polymer modification to improve the performance of organic dyes and expand their applications., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Two hydrophilic poly-vinylidene fluoride (PVDF) ultrafiltration membranes were prepared via in situ embedment of nanoparticles (NP), i.e., TiO 2 and Al 2 O 3 , respectively, and their anti-organic-fouling and anti-biofouling were comprehensively investigated. Characterization of modified PVDF-NP membranes by XRD and FTIR exhibited that nanoparticles were embedded successfully. Series of fast filtration tests demonstrated that in contrary to virgin PVDF membrane, PVDF-NP membranes have high permeability and anti-organic-fouling ability by decreasing the possibility of organic matters deposition and accumulation. Co-existed Ca 2+ in feed solution deteriorated the organic fouling in virgin PVDF and PVDF-NP membranes, which was mainly caused by gelation of macromolecular foulants. PVDF-NP membranes were used to form MBR modules for domestic wastewater treatment, and the long-term monitoring evidenced that hydrophilic modified membranes achieved stably high COD and [Formula: see text] rejection efficiencies, and better organic rejection capability than mAO process. PVDF-NP membranes possessed consistently high anti-biofouling ability to maintain stable membrane permeability.

Fundamental studies on the cellular uptake and drug release of PEGylated nanomedicines are beneficial to understand their fate in vivo and construct ideal nanoparticle formulations. In this work, the detailed metabolic process of PEGylated doxorubicin (Dox) nanomedicines were investigated via confocal laser scanning microscopy (CLSM), flow cytometry (FCM), cytotoxicity test, fluorescence imaging in vivo (FLIV) and liquid chromatography tandem mass spectrometry (LC-MS/MS). Among them, only LC-MS/MS could accurately determine the content of PEGylated Dox and Dox in vitro and in vivo. To the best of our knowledge, this was the first time the PEGylated Dox and released Dox were simultaneously quantified. The interplay of molecular structures, cellular uptake, drug release, and antitumor effect was well characterized. PEG with high molecular weight impeded the cellular uptake of nanoparticles, and the acid-labile hydrazone bond between Dox and PEG promoted Dox release significantly. Cellular uptake and drug release play decisive roles in cytotoxicity and antitumor effect, as evidenced by LC-MS/MS. We emphasized that LC-MS/MS would be a practicable method to quantify PEGylated drugs without complex tags, which could be more in-depth to understand the interaction between PEGylated nanomedicines and their antitumor efficacy.

Photothermal conversion in the second near-infrared (NIR-II) window allows deeper penetration and higher exposure to lasers, but examples of NIR-II photothermal agents are mainly formulated by inorganic compounds. In view of the underlying influence of inorganic materials, a novel NIR-II photothermal nanoagent based on a narrow band gap D-A conjugated polymer (TBDOPV-DT) with 2,2-bithiophene as the donor and thiophene-fused benzodifurandione-based oligo( p-phenylenevinylene) as the acceptor has been developed. More importantly, TBDOPV-DT nanoparticles (TBDOPV-DT NPs) are demonstrated to combine excellent photoacoustic imaging (PAI) and photothermal therapy (PTT) ability. TBDOPV-DT NPs exhibit dramatic photostability and heating reproducibility with a photothermal conversion efficiency of 50%. Especially, the NPs possess a remarkable PTT effect toward cancer cells in vitro and can eliminate tumor cells completely in vivo under 1064 nm laser irradiation, while no appreciable side effects have been observed. This study achieves PAI-guided cancer therapy and sheds light on the future of using organic polymer NPs for the NIR-II PTT of cancer.

Self-assembled small molecules, as a novel form of drug presentation, have splendid capabilities for water stability and cell endocytosis. Photodynamic therapy (PDT) is regarded as a promising cancer treatment because it is less invasive and has fewer side effects. In this work, an amphiphilic glycyrrhetinic acid-porphyrin conjugate (TPP-GA) was designed and synthesized, and this could self-assemble into nanoparticles (TPP-GA NPs) in water. The morphology of the TPP-GA NPs was observed using transmission electron microscopy (TEM) and their stability in water was revealed by dynamic light scattering (DLS). The PDT effect of the TPP-GA NPs was confirmed by means of in vitro experiment, after photostability verification. It could be conceived that the application of TPP-GA NPs for PDT is a feasible choice and this work shows progress in the self-assembly of amphiphilic small organic molecules.

All-trans-retinoic acid (RA) is a non-toxic physiological metabolite of vitamin A. A paclitaxel (PTX) prodrug (RA-PTX) with high PTX content of 75% was synthesized via an easy condensation reaction. RA-PTX nanoparticles (RA-PTX NPs) were prepared through a nanoprecipitation method which increased the water solubility of PTX. RA-PTX NPs were spherical in shape and exhibited favorable structural stability in both water and the physiological environment. RA-PTX NPs possessed effective cellular uptake as revealed by confocal laser scanning microscopy and exerted potent cytotoxicity. These results highlight the potential of nanomedicines from PTX prodrugs for increasing the drug loading and water solubility of PTX.

Polymeric nanoparticles (NPs) play a key role in nanoscale formulations for bioimaging, cancer treatment, and theranostics. In this work, we designed and synthesized a series of hydrophobic polymers (P1-6) with different pendent groups via one-step multicomponent Passerini reaction. These polymers possessed similar molecular structures and various biomedical functions. Interestingly, they could self-assemble into stable NPs in aqueous media. All formed NPs were redox sensitive because of the existence of disulfide bonds in the backbone. The stability of NPs in aqueous media with or without glutathione was systematically evaluated and compared. The optical performance, including fluorescence resonance energy transfer, was characterized under different conditions for those polymers with fluorescent components. Importantly, all formed NPs showed good cytocompatibility toward HeLa cells and different biological functions, including drug loading and delivery, bioimaging with variable fluorescence, and photodynamic activity, as evidenced by experiments in vitro and in vivo. These results demonstrate the great potential of multicomponent reaction to customize versatile polymeric nanoparticles for biomedical applications.

In this work, a glutamic acid linked paclitaxel (PTX) dimer (Glu-PTX 2 ) with high PTX content of 88.9wt% was designed and synthesized. Glu-PTX 2 could self-assemble into nanoparticles (Glu-PTX 2 NPs) in aqueous solution to increase the water solubility of PTX. Glu-PTX 2 NPs were characterized by electron microscopy and dynamic light scattering, exhibiting spherical morphology and favorable structural stability in aqueous media. Glu-PTX 2 NPs could be internalized by cancer cells as revealed by confocal laser scanning microscopy and exert potent cytotoxicity. It is envisaged that Glu-PTX 2 NPs would be an alternative formulation for PTX, and such amino acid linked drug dimers could also be applied to other therapeutic agents., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

An amphiphilic drug-dye conjugate (PTX-Pt-BDP) was designed and synthesized with a platinum compound as the hydrophilic head. The precursor of PTX-Pt-BDP was obtained under mild conditions by means of a three-component Passerini reaction. PTX-Pt-BDP could self-assemble into nanoparticles (PTX-Pt-BDP NPs) in aqueous solution via a nanoprecipitation method. The obtained nanoparticles exhibited favorable structural stability in both water and physiological environment. PTX-Pt-BDP NPs could be endocytosed by cancer cells as revealed by confocal laser scanning microscopy and exert potent cytotoxicity. This work highlights the potential of nanomedicines from amphiphilic drug-dye conjugates for cancer cell imaging and chemotherapy., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Two fluorescent nanomedicines based on small molecular cyanine-platinum conjugates have been prepared via a nanoprecipitation method and characterized by transmission electron microscopy (TEM) as well as dynamic light scattering (DLS). The conjugates exhibited an enhanced fluorescence in their nanoparticle formulation compared to that in solution. The nanomedicines could be endocytosed by cancer cells as revealed by confocal laser scanning microscopy (CLSM) and showed high cellular proliferation inhibition. Fluorescent platinum nanomedicines prepared directly from small molecules could be an alternative strategy for developing new drugs with simultaneous cellular imaging and cancer therapy functions., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A new photothermal nano-agent was obtained by the coprecipitation of 2,5-Bis(2,5-bis(2-thienyl)-N-dodecyl pyrrole) thieno[3,4-b][1,2,5] thiadiazole (TPT-TT) and a biodegradable amphiphilic block copolymer, methoxypoly(ethylene glycol)2K-block-poly(D,L-lactide)2K (mPEG2K-PDLLA2K). TPT-TT, a donor-acceptor-donor (D-A-D) type small molecule, with bis(2-thienyl)-N-alkylpyrrole (TPT) as the donor and thieno[3,4-b]thiadiazole (TT) as the acceptor was a strong near infrared (NIR) absorber, which could convert the absorbed light energy into heat. The formation of TPT-TT nanoparticles (TPT-NPs), which possessed high stability in water, was confirmed by dynamic light scattering (DLS) and transmission electron microscopy (TEM). TPT-NPs showed high photothermal conversion efficiency (32%) and excellent photostability and heating reproducibility. The photostability of TPT-TT NPs was much better than that of indocyanine green (ICG), a federal drug administration (FDA) approved NIR dye. Besides, TPT-TT NPs exhibited significant photothermal therapeutic effect toward human cervical carcinoma (HeLa) and human liver hepatocellular carcinoma (HepG2) cells, while no appreciable dark cytotoxicity was observed. These results highlight the potential of TPT-TT NPs as an effective photothermal agent for cancer therapy., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Magnetic poly (D,L-lactide-co-glycolide) (PLGA)/lipid nanoparticles (MPLs) were fabricated from PLGA, L-α-phosphatidylethanolamine (DOPE), 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-amino (polyethylene glycol) (DSPE-PEG-NH2), and magnetic nanoparticles (NPs), and then conjugated to trans-activating transcriptor (TAT) peptide. The TAT-MPLs were designed to target the brain by magnetic guidance and TAT conjugation. The drugs hesperidin (HES), naringin (NAR), and glutathione (GSH) were encapsulated in MPLs with drug loading capacity (>10%) and drug encapsulation efficiency (>90%). The therapeutic efficacy of the drug-loaded TAT-MPLs in bEnd.3 cells was compared with that of drug-loaded MPLs. The cells accumulated higher levels of TAT-MPLs than MPLs. In addition, the accumulation of QD-loaded fluorescein isothiocyanate (FITC)-labeled TAT-MPLs in bEnd.3 cells was dose and time dependent. Our results show that TAT-conjugated MPLs may function as an effective drug delivery system that crosses the blood brain barrier to the brain.

Metal oxide nanoparticles (NPs) are among the most highly produced nanomaterials, and have many diverse functions in catalysis, environmental remediation, as sensors, and in the production of personal care products. In this study, the toxicity of several widely used metal oxide NPs such as copper oxide, silica, titanium oxide and ferric oxide NPs, were evaluated In vitro. We exposed A549, H1650 and CNE-2Z cell lines to metal oxide NPs, and found CuO NPs to be the most toxic, SiO2 mild toxic, while the other metal oxide NPs had little effect on cell viability. Furthermore, the autophagic biomarker LC3-II significantly increased in A549 cells treated with CuO NPs, and the use of the autophagy inhibitors wortmannin and 3-methyladenin significantly improved cell survival. These results indicate that the cytoxicity of CuO NPs may involve the autophagic pathway in A549 cells.

Three-dimensionally ordered macro-/mesoporous carbon (OMMC)-supported Ag nanoparticles (Ag/OMMC) with homogeneously dispersed Ag particles are prepared and investigated as effective electrocatalysts for oxygen reduction reaction (ORR) in alkaline aqueous system. The obtained Ag/OMMC catalyst displays smaller Ag particle size, higher Ag dispersion, and enhanced catalytic activity and durability compared with the carbon black Vulcan XC-72R supported Ag (Ag/XC-72R). The sizes of Ag particles supported on the OMMC and XC-72R are 4.3 and 6.5 nm, respectively. The prepared Ag/OMMC catalyst shows a positive half-wave potential of 0.79 V vs. RHE and a large diffusion-limited current of 5.6 mA cm−2 at 0.4 V, superior to Ag/XC-72R catalyst. The better ORR performance of the Ag/OMMC is probably ascribed to the unique 3D ordered interconnected macro-/mesoporous structure, which contributes to facilitating the mass/charge transport, improving the Ag particle dispersion, and preventing the Ag particle growth and aggregation. [ABSTRACT FROM AUTHOR]

Targeting imaging to the desired site of action can increase the accuracy and effectiveness of diagnostic and treatment. In this work, a series of fluorescent carbon dots (CDs) were prepared by varying molar ratios of d -glucose (Glu) to l -aspartic acid (Asp). Their photophysical properties, morphologies and structures were investigated in detail. More important, the targeting ability was screened by confocal laser scanning microscopy and flow cytometry. The results indicate that CDs prepared from the optimal molar ratio of Glu/Asp (7:3) exhibit the highest targeting ability on C6 glioma cells. This work highlights the interplay of molecular design and corresponding functions, and open new possibility of developing state-of-art nanoparticles for biomedical applications. [ABSTRACT FROM AUTHOR]

An amphiphilic drug-dye conjugate ( PTX-Pt-BDP) was designed and synthesized with a platinum compound as the hydrophilic head. The precursor of PTX-Pt-BDP was obtained under mild conditions by means of a three-component Passerini reaction. PTX-Pt-BDP could self-assemble into nanoparticles ( PTX-Pt-BDP NPs) in aqueous solution via a nanoprecipitation method. The obtained nanoparticles exhibited favorable structural stability in both water and physiological environment. PTX-Pt-BDP NPs could be endocytosed by cancer cells as revealed by confocal laser scanning microscopy and exert potent cytotoxicity. This work highlights the potential of nanomedicines from amphiphilic drug-dye conjugates for cancer cell imaging and chemotherapy. [ABSTRACT FROM AUTHOR]

PtNi alloy nanoparticles anchored on the hierarchically ordered macro-/mesoporous Co, N-doped carbon (PtNi/Co-N-OMMC) contribute to superior electrocatalytic performances for oxygen reduction under acidic condition. [Display omitted] • Co-N-OMMC has ordered macro-/mesoporous structure and high specific surface area. • PtNi alloy particles are uniformly dispersed on Co-N-OMMC. • The synergistic effect between Co-N-OMMC and PtNi leads to good ORR activity. Herein, an ORR electrocatalyst with ultrafine PtNi alloy nanoparticles (sub-10 nm) anchored on the hierarchically ordered macro-/mesoporous Co, N-doped carbon (PtNi/Co-N-OMMC) is developed via an dual-template-assisted pyrolysis combined with one-step solvothermal method. As inspired, the PtNi/Co-N-OMMC catalyst shows superior ORR activity (half-wave potential (E 1/2) of 0.92 V) and high durability (negligible loss in E 1/2 over 2000 potential cycles) in acidic condition. The remarkable property of the PtNi/Co-N-OMMC catalyst for ORR benefits from the synergistic catalytic effect between PtNi nano-alloys and Co-N-OMMC for accelerating the reaction, the anchoring effect of the Co-N-OMMC support for suppressing nanoparticle migration and corrosion, the large surface area for highly dispersing PtNi nanoparticles and 3D interconnected ordered macro-/mesoporous structure for enhancing mass/charge transport throughout the electrode. [ABSTRACT FROM AUTHOR]

Herein, different loading of Ni 2 P nanoparticles anchored on 3D Co-N-doped ordered macro-/mesoporous carbon (Ni 2 P/CoN-OMMC) were synthesized. The optimized Ni 2 P/CoN-OMMC-40 ​wt% catalyst with 40 ​wt% Ni 2 P loading exhibits the best electrocatalytic HER activity under strong acidic conditions, showing an extremely low overpotential of 69 ​mV at 10 ​mA ​cm−2 and a small Tafel slope of 38 ​mV dec−1. The highly distributed active Ni 2 P nanoparticles and the unique macro-mesoporous CoN-OMMC support that is beneficial for promoting the active site exposure and mass/electron transport may contribute synergistically to the remarkable HER catalytic performance. [Display omitted] We have prepared a series of catalysts with different loading of Ni 2 P nanoparticles embedded in Co–N-doped ordered macro-/mesoporous carbon support (Ni 2 P/CoN-OMMC). The optimal Ni 2 P/CoN-OMMC-40 ​wt% catalyst with 40 ​wt% Ni 2 P loading shows excellent electrocatalytic performances for HER under acidic electrolyte with an extremely low overpotential of 69 ​mV at 10 ​mA ​cm−2 and a small Tafel slope of 38 ​mV dec−1, as well as a remarkable long-term durability. • Ni 2 P particles anchored on Co,N-doped ordered macro-/mesoporous carbons are prepared. • HER activity relates to the loading of Ni 2 P particles. • Optimal electrocatalyst exhibits excellent HER activity and durability. • Active Ni 2 P particles and ordered porous structure contribute to high HER property. [ABSTRACT FROM AUTHOR]

Supported Pd nanoparticle catalystsover Mg–Al mixed metal oxides derived from layered double hydroxideswere prepared by three different approaches, including coprecipitation,anion-exchange, and impregnation, in order to enhance the metal dispersionand thus facilitate the growth of uniform multiwalled carbon nanotubes(CNTs) via catalytic chemical vapor deposition of methane. The effectsof preparation methods for supported Pd catalysts on the morphologiesand microstructures of CNTs formed were investigated. The resultsrevealed that the characteristics of CNTs were strongly correlatedto the dispersion of active Pd species in the catalysts, and the structuraldefects and the diameter of CNTs were reduced with the increasingmetal dispersion. Especially, the anion-exchange route for preparationof supported Pd catalyst was appropriate for the growth of uniformbamboo-like CNTs with fewer defects, which could be contributed tothe presence of more uniform and smaller Pd0nanoparticleshighly dispersed over Mg–Al mixed-metal oxides. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The pure BODIPY nanoparticles are made from hydrophobic BODIPY molecules in the absence of surfactants or auxiliaries. • The BODIPY nanoparticles possess excellent colloid stability, near 100% of BODPIY, and particular physicochemical properties. • The BODIPY nanoparticles can be used for tumor imaging and treatment upon irradiation. Abstract 4,4-Difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) as the robust dyes have been widely applied in biomedical areas, especially for tumor imaging and phototherapy. Most of the BODIPY dyes are hydrophobic, so the nanoparticle formulations are imperative for their dispersion in physiological conditions. The nanoparticles are usually obtained in the presence of surfactants or auxiliaries. In recent years, our group and others have reported the pure BODIPY nanoparticles (BODIPY NPs), which were prepared via the self-assembly of BODIPY molecules in aqueous solution without addition of any surfactants. These BODIPY NPs possess excellent colloid stability, near 100% of BODIPY, and particular physicochemical properties, which could be potentially used in cancer treatment and diagnosis. In this review, we will summarize and highlight the reported unadulterated organic nanoparticles based on BODIPY dyes and their application in bioimaging and cancer therapy to provide a paradigm of rational design of novel BODIPY photosensitizers for biomedical applications. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Theranostics, integrating tumor treatment and diagnosis concurrently, has become an emerging and meaningful strategy in cancer therapy. In this work, an amphiphilic redox-sensitive near-infrared (NIR) BODIPY dye, which could be formed into nanoparticles (PEG-SS-BDP NPs) by self-assembly, was synthesized and possessed good capability of photothermal therapy (PTT), near-infrared fluorescence (NIRF) imaging, photoacoustic (PA) imaging and drug loading. The stable nanoparticles could be dissociated to turn on NIRF due to the rift of embedded disulfide bonds by glutathione (GSH). The enhanced fluorescence in vitro could be observed via confocal laser scanning microscopy (CLSM) after adding GSH, confirming the redox-sensitivity of disulfide bonds. NIRF and PA imaging demonstrated active accumulation in tumor and good imaging effect. At last, PEG-SS-BDP NPs could significantly suppress tumor growth in vivo upon irradiation. The amphiphilic redox-sensitive BODIPY nanoparticles provide a promising design strategy to formulate multifunctional stimuli-responsive theranostic nanoplatforms. [ABSTRACT FROM AUTHOR]

Nowadays, developing efficient and low-cost catalysts to catalyze oxygen reduction reaction (ORR) is important to alleviate environmental pollution and energy scarcity. Herein, we describe an ORR electrocatalyst that anchors Co–Fe alloy nanoparticles (NPs) on the carbon support obtained from biomass (Sichuan pepper powder), which can effectively convert O 2 into water. The precursor containing cobalt phthalocyanine and Sichuan pepper powder is modified with nitrogen-rich ligand-pyrrole by using FeCl 3 as the initiator, and then the nitrogen-rich Co–Fe-based biomass carbon catalyst is synthesized by highly efficient one-step pyrolysis at 900 ​°C (defined as FeCoNC-900). It was found that not only Co–Fe alloy nanoparticles were produced, but also graphene-packaged metallic Fe 3 C nanocrystals around Co–Fe alloy nanoparticles were formed during the pyrolysis. The results show that the best performing catalyst (FeCoNC-900) exhibits higher half-wave potential (0.91 ​V vs. reversible hydrogen electrode (RHE)) and better stability in an alkaline electrolyte in comparison with the 20 ​wt% Pt/C. [Display omitted] By using cheap biomass as the carbon source, we prepared a carbon-based catalyst including Co–Fe alloy nanoparticles and Fe 3 C nanocrystals supported on N-doped porous carbon through a one-step pyrolysis strategy. This catalyst showed excellent electrocatalytic activity and durability for oxygen reduction reaction (ORR) and even superior to commercial Pt/C under an alkaline electrolyte. • A Co–Fe alloy ORR catalyst is synthesized by a simple one-step pyrolysis strategy. • The catalyst exhibits excellent electrocatalytic ORR activity and durability. • Biomass carbon opens the way for the commercial applications of carbon-based catalysts. [ABSTRACT FROM AUTHOR]