Black Phosphorus Quantum Dots Research Articles

Black Phosphorus Quantum Dot Loaded Bioinspired Nanoplatform Synergized with aPD-L1 for Multimode Cancer Immunotherapy.

Efforts to prolong the blood circulation time and bypass immune clearance play vital roles in improving the therapeutic efficacy of nanoparticles (NPs). Herein, a multifunctional nanoplatform (BPP@RTL) that precisely targets tumor cells is fabricated by encapsulating ultrasmall phototherapeutic agent black phosphorus quantum dot (BPQD), chemotherapeutic drug paclitaxel (PTX), and immunomodulator PolyMetformin (PM) in hybrid membrane-camouflaged liposomes. Specifically, the hybrid cell membrane coating derived from the fusion of cancer cell membrane and red blood cell membrane displays excellent tumor targeting efficiency and long blood circulation property due to the innate features of both membranes. After collaboration with aPD-L1-based immune checkpoint blockade therapy, a boosted immunotherapeutic effect is obtained due to elevated dendritic cell maturation and T cell activation. Significantly, laser-irradiated BPP@RTL combined with aPD-L1 effectively eliminates primary tumors and inhibits lung metastasis in 4T1 breast tumor model, offering a promising treatment plan to develop personalized antitumor strategy.

Biomimetic nanodrug blocks CD73 to inhibit adenosine and boosts antitumor immune response synergically with photothermal stimulation

Combination of tumor immunotherapy with photothermal therapy (PTT) is a feasible tactic to overcome the drawback of immunotherapy such as poor immune response. Via triggering the immunogenic cells death (ICD), PTT can stimulate the activity of immune cells, but meanwhile, the level of adenosine is elevated via the CD73-induced decomposition of ATP which is overexpressed accompanying with the PTT process, resulting in negative feedback to impair the immune stimulation. Herein, we developed a novel biomimetic photothermal nanodrug to specifically block CD73 for inhibition of adenosine production and more efficient priming of the suppressive immune microenvironments. The nanodrug, named as AptEM@CBA, is constructed by encapsulation of photothermal agent black phosphorus quantum dots (BPQDs) and selective CD73 inhibitor α, β-Methyleneadenosine 5′-diphosphate (AMPCP) in chitosan nanogels, which are further covered with aptamer AS1411 modified erythrocyte membrane (EM) for biomimetic camouflage. With AS1411 induced active targeting and EM induced long blood circulation time, the enrichment of the nanodrug tumor sites is promoted. The photothermal treatment promotes the maturation of dendritic cells. Meanwhile, the release of AMPCP suppress the adenosine generation via CD73 blockade, alleviating the impairment of adenosine to dendritic cells and suppressing regulatory T cells, synergically stimulate the activity of T cells. The combination of CD73 blockade with PTT, not only suppresses the growth of primary implanted tumors, but also boosts strong antitumor immunity to inhibit the growth of distal tumors, providing good potential for tumor photoimmunotherapy.

Polyphenols functionalized MOF encapsulated BPQDs for synergistic photothermal/photodynamic antibacterial properties and multifunctional food preservation

Active antibacterial materials play an important role in solving food safety problems caused by pathogen contamination. In this study, a composite active antibacterial material with the synergistic antibacterial effectiveness of photothermal, photodynamic and the surface charge of polyphenols was developed, where the multi-porous polyphenol functionalized metal–organic frameworks (ZIF-8-TA) were used as the framework carrier, and black phosphorus quantum dots (BPQDs) were used as the photosensitive source. The resulted ZIF-8-TA/PBQDs possesses excellent photothermal conversion efficiency (27.92%), photodynamic performance and surface charge, and these factors ensure the outstanding broad-spectrum antibacterial performance (100%). Multifunctional characteristics and excellent biocompatibility endow the materials with vast potential for foodstuff packaging. The results showed that the composite antibacterial film produced by doping ZIF-8-TA/PBQDs into chitosan could effectively prolong the shelf life of foodstuff compared with commercial membrane. The successful implementation of this research provides a new idea for controlling microbial contamination and developing multifunctional antibacterial materials.

Subacute exposure to black phosphorus quantum dots induces cardiac fibrosis and the potential role of gut microbiota

Black phosphorus quantum dots (BPQDs) have been used as the nano-carrier in the field of biomedicine due to their excellent electronic conductivity, optical and thermoelectric properties. However, it is still lack of evaluation of the safety of BPQDs, specifically on the effects and mechanisms of BPQDs on heart. In this study, the specific pathogen-free male mice were orally administered with different doses of BPQDs (0.02, 0.1, 0.5 mg/kg) for 28 days. BPQDs exposure decreased the heart-body ratio and caused cardiac hypertrophy and fibrosis. Additionally, ferroptosis was observed in the cardiac tissue. The recent study has shown BPQDs oral exposure alter gut microbiota. Here, after exposure to 0.1 mg/kg BPQDs for 28 days, the germ-free mice showed neither cardiac injury nor ferroptosis. Taken together, the study demonstrates that BPQDs induce cardiac ferroptosis and fibrosis, possibly mediated by gut microbiota. This research may aid in enhancing understanding of the biosafety of BP nanomaterials and promoting the sustainable development of nanotechnology.

Controllable preparation of black phosphorus nanomaterials via liquid-phase pulsed discharge

The N, N-dimethylformamide (DMF) organic solvent was deliberately chosen as the optimal medium for this investigation. To achieve uniform dispersion of black phosphorus powder, which was obtained via shock-induced phase transformation, it was effectively dispersed in the DMF solution, resulting in a homogeneous black phosphorus-DMF suspension. Subsequently, a liquid-phase pulsed discharge experiment was conducted. This experimental setup harnessed the shockwave and tensile stripping effects generated by the rapid expansion of plasma during the liquid-phase pulsed discharge. These phenomena facilitated the interlayer exfoliation and dispersion of black phosphorus molecules, ultimately leading to the formation of a suspension containing black phosphorus quantum dots. In-depth investigation into the formation mechanism of black phosphorus quantum dots was also undertaken. Our findings reveal a pivotal influence of the charging voltage on the microstructure of the recovered samples. Specifically, as the charging voltage increases, the lateral dimensions of the retrieved two-dimensional black phosphorus powder undergo a remarkable reduction, transitioning from the micron-scale to less than 10 nm. The above results, which stem from meticulous experimentation and analysis, emphasize the significance of controlled synthesis in producing black phosphorus quantum dots with varying microstructures. Such insights hold substantial promise for advancing the field of materials science and enhancing the applicability of black phosphorus quantum dots in diverse applications.

Black Phosphorus Microbubbles Combined with Ultrasound for Treating Parkinson's Disease

AbstractParkinson's disease (PD) is a common chronic central nervous system disorder that reduces quality of life and increases mortality. Currently, the treatment of PD is limited due to the challenge of macromolecular drugs crossing the blood‐brain barrier (BBB). Black phosphorus (BP) has antioxidant and anti‐inflammatory effects and shows potential for neuroprotection. To solve the restriction of the BBB, innovative BP microbubbles (BP@MBs) combined with focused ultrasound (FUS) are constructed to facilitate BBB opening. Additionally, the biocompatibility and safety of BP@MBs with varying dimensions are investigated, including BP quantum dot microbubbles (BPQDs@MBs) and BP nanosheet microbubbles (BPNSs@MBs). The findings indicate that low concentrations of BP have good biosafety and that BPQDs@MBs exhibit better biocompatibility than BPNSs@MBs both in vitro and in vivo at the same concentrations. Moreover, a 6‐hydroxydopamine (6‐OHDA)‐induced PD cell model and an animal model are established to verify the anti‐PD effects of BPQDs@MBs and BPNSs@MBs. The results confirmed that BPQDs@MBs and BPNSs@MBs have antioxidant effects that reduced neuronal apoptosis and improved the motor symptoms of PD in rats. BPQDs@MBs combined with FUS may be a promising option for the clinical treatment of PD.

Sonoelectrochemical exfoliation of defective black phosphorus nanosheet with black phosphorus quantum dots as a uric acid sensor

To maintain human health, the development of rapid uric acid (UA) sensing is crucial. In this study, defective black phosphorus nanosheets with black phosphorus quantum dots (dBPN/BPQDs) were successfully and rapidly prepared by sonoelectrochemical exfoliation. In this process, the intercalation of phosphate ions into the black phosphorus working electrode was improved by coupling ultrasonic radiation with a high intercalating potential (8 V vs. Ag/AgCl/3M). The dBPN/BPQDs with various vacancies (5–9 defects, 5-7-7-5 defects, and 5-8-5 defect vacancies) exhibited a remarkable mass activity (jm, 1.22 × 10−3 mA μg−1) for uric acid oxidation, which was 5.92 times greater than that of reduced graphene oxide (rGO) (2.06 × 10−4 mA μg−1). In addition, the sensitivity of the dBPN/BPQD UA sensor was 474.2 μA mM−1 cm−2 in the linear analysis range of 0.1–1.3 mM. The sensitivity of the sensor was apparently higher than 67.7 μA mM−1cm−2 for rGO. The data from real sample experiments using serum showed that the dBPN/BPQD catalyst had high recoveries (97.3 %–100.2 %) and low related standard deviation (0.44 %–1.52 %). The dBPN/BPQDs exhibited the potential as an amperometric sensor to detect UA without needing enzymes.

A theragenerative bio-nanocomposite consisting of black phosphorus quantum dots for bone cancer therapy and regeneration

Recently, the term theragenerative has been proposed for biomaterials capable of inducing therapeutic approaches followed by repairing/regenerating the tissue/organ. This study is focused on the design of a new theragenerative nanocomposite composed of an amphiphilic non-ionic surfactant (Pluronic F127), bioactive glass (BG), and black phosphorus (BP). The nanocomposite was prepared through a two-step synthetic strategy, including a microwave treatment that turned BP nanosheets (BPNS) into quantum dots (BPQDs) with 5 ± 2 nm dimensions in situ. The effects of surfactant and microwave treatment were assessed in vitro: the surfactant distributes the ions homogenously throughout the composite and the microwave treatment chemically stabilizes the composite. The presence of BP enhanced bioactivity and promoted calcium phosphate formation in simulated body fluid. The inherent anticancer activity of BP-containing nanocomposites was tested against osteosarcoma cells in vitro, finding that 150 μg mL−1 was the lowest concentration which prevented the proliferation of SAOS-2 cells, while the counterpart without BP did not affect the cell growth rate. Moreover, the apoptosis pathways were evaluated and a mechanism of action was proposed. NIR irradiation was applied to induce further proliferation suppression on SAOS-2 cells through hyperthermia. The inhibitory effects of bare BP nanomaterials and nanocomposites on the migration and invasion of bone cancer, breast cancer, and prostate cancer cells were assessed in vitro to determine the anticancer potential of nanomaterials against primary and secondary bone cancers. The regenerative behavior of the nanocomposites was tested with healthy osteoblasts and human mesenchymal stem cells; the BPQDs-incorporated nanocomposite significantly promoted the proliferation of osteoblast cells and induced the osteogenic differentiation of stem cells. This study introduces a new multifunctional theragenerative platform with promising potential for simultaneous bone cancer therapy and regeneration.

A responsive hydrogel modulates innate immune cascade fibrosis to promote ocular surface reconstruction after chemical injury

Following an ocular chemical injury, the release of neutrophil extracellular traps (NETs) triggers an innate immune cascade fibrotic effect involving macrophages (Mø), which limits corneal repair. However, the interplay and mechanisms between NETs and macrophages, as well as the coordination between the innate immunity and corneal repair, remain challenging issues. Using a co-culture system, we report that chemical stimulation exacerbates the accumulation of reactive oxygen species (ROS) within the polymorphonuclear neutrophils, leading to NET formation and the activation of M2 macrophages, ultimately inducing pathological fibrosis of the ocular surface through the IL-10/STAT3/TGF-β1/Smad2 axis. Inspired by the locally formed acidic microenvironment mediated by innate acute inflammatory stimulation, we further integrate sericin with oxidized chitosan nanoparticles loaded with black phosphorus quantum dots (BPQDs) using Schiff base chemistry to construct a functional pH-responsive hydrogel. Following corneal injury, the hydrogel selectively releases BPQDs in response to the acidic environment, inhibiting the innate immune cascade fibrosis triggered by the PMN-ROS-NETs. Thus, corneal pathological fibrosis is alleviated and reshaping of the ocular surface takes place. These results represent a refinement of the mechanism of inherent immune effector cell interactions, and provide new research ideas for the construction of nano biomaterials that regulate pathological fibrosis.

Lipid-nanoparticles-based co-delivery of black phosphorus quantum dots and melphalan by photothermal therapy combined with chemotherapy for retinoblastoma

Melphalan is an efficient chemotherapeutic agent for retinoblastoma (RB) in clinical practice. However, the problems of drug resistance and poor prognosis caused by long-term treatment of melphalan should not be ignored. At present, it is urgent to find a therapeutic strategy to enhance the curative effect to solve the need for clinical treatment of RB to protect eyesight. Herein, we propose an effective strategy to encapsulate melphalan and black phosphorus quantum dots (BPQDs) with high-biocompatibility liposomes for photothermal therapy (PTT) to enhance cell killing. BPQDs and melphalan were encapsulated using liposomes with a similar structure to the cell membrane, and a lipid nanoparticle with both photothermal and chemical inhibition effects was prepared. The obtained nanoparticle has a spherical shape (particle size range of 82–180 nm) and good stability (encapsulation efficiencies of melphalan of 40 % and BPQDs of 43.7 %). Its temperature increased to 65 °C within 10 min under a 2 W/cm2 laser at 808 nm, exerting photothermal and synergistic effects with melphalan to induce apoptosis of tumor cells. As expected, the prepared nanoparticle effectively inhibits tumor proliferation, upregulates the ki67 expression level, and has an excellent PTT effect on the orthotopic xenograft of WERI-RB-1 cells.

Optical tuning of the terahertz response of black phosphorus quantum dots: effects of weak carrier confinement

Abstract In contrast to few-layer black phosphorus (BP) with a relatively larger area, BP quantum dots (BP-QDs) are expected to have distinctive electromagnetic response and carrier behaviors, especially in low-frequency range such as in the THz regime. Herein, we experimentally investigate the THz properties of BP-QDs as well as the optical control of these properties. It is demonstrated that the effects of weak carrier confinement, which is associated with diffusive restoring current in each BP-QD, contribute significantly to the effective THz conductivity of BP-QDs. Instead, spectral features of discretely spaced energy levels as shown for many kinds of semiconductor QDs in UV-visible range are not observed in the THz regime. This indicates an insignificant contribution of strong quantum confinement here. Based on the modified Drude–Smith formula, we show that the optical excitation/pump of a CW laser can induce photogenerated carriers and enhance the effects of weak carrier confinement in BP-QDs. Thus, a nonlinear enhancement of THz absorption can be observed by increasing the power of the excitation laser. These results not only deepen our understanding of the fundamental physics of BP nanomaterials but also provide an alternative approach to realize active control of BP-based THz devices.

Optical fiber Fabry–Perot sensor based on BPQDs-PVA compound for humidity measurement

A high-sensitivity fiber humidity sensor based on Fabry–Perot interferometer is experimentally proposed. The sensor is fabricated by coating black phosphorus quantum dots (BPQDs)-polyvinyl alcohol (PVA) film on the end face of single mode fiber via controllable dipping method. Benefit from the BPQDs-PVA based cavity, the length and the refractive index of the BPQDs-PVA compound changes with ambient humidity, evidently modulating the interference spectrum. Experimental results show that the sensor achieves a maximum humidity sensitivity of 4.844 nm/%RH in the humidity range of 33%–56%RH with a low temperature cross sensitivity of 0.017%RH °C−1. Meanwhile, stability test exhibits a low instability of 0.016%RH. Together with the advantages of simple manufacture, small size and fast response, the sensor has broad practical application prospect.

Nitrogen-doped reduced graphene oxide/black phosphorus quantum dot composites for electrocatalytic treatment of choroidal melanoma

Choroidal melanoma (CM) is a melanocyte-derived intraocular malignancy that poses a great threat to patients’ vision and life. Electrochemical therapy, which relies on the generation of reactive oxygen species via an oxygen reduction reaction (ORR) to kill target cells, has emerged as a promising approach for the local treatment of malignant tumors. In this study, nitrogen-doped reduced graphene oxide (N-rGO) was electrostatically bound with black phosphorus (BP) quantum dots to form a composite system (N-rGO-BP) for tumor therapy. Owing to the synergistic effect of the two components, the optimal catalyst (N-rGO-BP-12) exhibits improved electrochemical properties and stability, achieving a more positive half-wave potential of 0.66 V and a larger steady-state current density of 2.76 mA cm−2 compared with the N-rGO precursor. In electrochemical therapy, N-rGO-BP-12 undergoes ORR via a two-electron pathway in the acidic microenvironment of the tumor, producing large amounts of hydrogen peroxide and hydroxyl radical to kill tumor cells; only 25 % of the human CM cells survive after 3 h of the treatment. This study provides a new approach for the synthesis and application of electrochemical catalysts for clinical tumor therapy.

Composite nanoarchitectonics for efficient lithium storage by encapsulating black phosphorus quantum dots in cobalt/iron based Prussian blue analogues

It is the critical to efficiently using black phosphorus quantum dots (BQ) in lithium batteries to obtain high energy density with improved stability. In this work, BQ was encapsulated in the size-matched pores of metal-organic frameworks (MOF) Cobalt/Iron-based Prussian blue analogues (Co/Fe-based PBA) by a coprecipitation method to construct a series of Co/Fe-based PBA@xBQ composite materials. The composite materials added with BQ exhibit significantly improved stability, demonstrating excellent electrochemical performances in lithium batteries. The close contact of BQ with Co/Fe catalytic sites promoted the rapid transfer of lithium ions between the metal sites. The unique structure of black phosphorus allowed storing more lithium ions in the pores of Co/Fe-based PBA. Grafting the surface of MOF with BQ could reduce side reactions on the electrode surface, and their synergistic effects enhanced the lithium storage capacity. The energy density of Li||Co-Co PBA@ 8BQ and Li||Fe-Co PBA@ 10BQ batteries was 130.5 mAh·g−1 and 187.4 mAh·g−1 higher than the Li||Co/Fe-based PBA. Li||Fe-Co PBA@ 10BQ battery had a long cycle stability, with 70% capacity retention rate after 500 cycles. The new composite materials achieved the combination of BQ and PBA to obtain lithium batteries with higher capacity density and stability with more cycles.

Black phosphorus quantum dots induced ferroptosis in lung cell via increasing lipid peroxidation and iron accumulation.

Black Phosphorus Quantum Dots (BP-QDs) have potential applications in biomedicine. BP-QDs may enter the body through the respiratory tract during grinding and crushing production and processing, causing respiratory toxicity. Ferroptosis is an oxidative, iron-dependent form of cell death. Here, respiratory toxicity of BP-QDs has been validated in mice and human bronchial epithelial cells. After 24h of exposure to different doses (4-32μg/mL) of BP-QDs, intracellular lipid peroxidation and iron overload occurred in Beas-2B cells. After 4 times exposures by noninvasive tracheal instillation at four doses [0, 0.25, 0.5 and 1 (mg/kg/48h)], all animals were sacrificed, organs were removed, processed for pathological examination and molecular analysis. Iron overload, glutathione (GSH) depletion and lipid peroxidation in the lung tissue of mice in the exposure group. Furthermore, based on the ferroptosis-associated protein and mRNA expression, it was hypothesized that BP-QDs induced ferroptosis through increasing intracellular free iron and polyunsaturated fatty acid synthesis. By comparing with previous studies, we speculate that primary cells generally are more sensitive to BP-QDs-induced damage than cancer cells. In summary, findings in the present study confirmed that BP-QDs induce ferroptosis via increasing lipid peroxidation and iron accumulation in vitro and in vivo.

Stabilizing α-FAPbI3 at FAPbI3/SnO2-X Interface By Reducing Oxygen Vacancies in SnO2-X

CH3NH3PbI3 (CH3NH3 + is denoted MA hereinafter) was selected as the photoactive material in the early stage of perovskite solar cell (PSC) research. However, MAPbI3 shows poor thermal stability due to high volatility of the MA organic cation. Replacing the MA organic cation with a CH(NH2)2 + (CH(NH2)2 + is denoted FA hereinafter) organic cation was suggested to resolve the thermal stability issue. Additionally, FAPbI3 holds higher potential for high-efficiency solar cells with a broader photoresponse range in the solar spectrum than MAPbI3. However, fabricating FAPbI3 thin films is more challenging than MAPbI3. FA exhibits a larger ionic size (2.56 Å) than MA (2.17 Å), making incorporation of FA into PbI6 octahedra difficult. Incorporating FA induces tilting of PbI6 octahedra, which causes reversible deformation of perovskite-phase FAPbI3 (α-phase) into unfavorable phases (δ-phase and PbI2) at room temperature. Several reports on stabilizing the α-phase of FAPbI3, such as through heterogeneous cation or anion mixing, have been presented. For example, mixing smaller ions such as MA, Cs, and Br reduces the unit cell volume of FAPbI3, enhancing hydrogen bonding between FA and the PbI6 octahedron. This hydrogen bonding prevents reversible deformation of and stabilizes the α-phase of FAPbI3 in ambient atmosphere. In conventional PSCs, the perovskite layer usually forms an interface with an electron or hole transport layer (ETL or HTL). The compatibility of materials forming the interface is significant for separating charges from the perovskite with minimal loss. Nevertheless, although stabilizing FAPbI3 in a bulk manner is widely studied, stabilizing FAPbI3 at the interface is relatively overlooked. Stabilizing FAPbI3 at the interface is more important since the interface contains a high portion of structural defects compared to the bulk, almost 100-fold. Unfavorable phases, such as δ-phase FAPbI3 and PbI2, formed at the interface will hinder the charge extraction process from FAPbI3 to the transport layer, similar to defects. Especially, in the n-i-p structure, the perovskite is epitaxially deposited over the ETL, and tuning the interface after deposition is nearly impossible, which stresses the importance of the surface structure of the ETL. In the case of FAPbI3/SnO2-x, Sn and O are the key atoms for stabilizing the PbI6 octahedron and organic cation, respectively, which affects the growth of the perovskite at the interface. Oxygen vacancies in the surface of SnO2-x can cause distortion of the perovskite structure at the interface, inducing unfavorable phases, such as the δ-phase, PbI2, or other unknown phases. Furthermore, oxygen vacancies are more prevalent issue in SnO2-x than TiO2-x due to the stronger multivalency of Sn, which further emphasizes control of oxygen vacancies in SnO2-x. Since the open-circuit voltage (Voc) and fill factor (FF) show greater potential for improvement than the short-circuit current density (Jsc), stabilizing α-FAPbI3 at the interface may be a necessary step for researchers to further increase the power conversion efficiency (PCE) and stability of PSCs. In this work, we systematically studied the formation of δ-phase FAPbI3 and PbI2 induced by oxygen vacancies of the SnO2-x surface at the FAPbI3/SnO2-x interface. Using X-ray diffraction (XRD) and transmission electron microscopy (TEM), we observed PbI2 segregation and δ-phase FAPbI3 formation adjacent to SnO2-x. The generation of iodine interstitials at the interface was revealed as the driving force of the unfavorable phase transition. The absence of oxygen atoms interacting with tin atoms lowered the energy barrier for iodine interstitial generation almost by half, and the iodine interstitials accelerated the unfavorable phase transition of FAPbI3. For the first time, organic cation loss at the FAPbI3/SnO2-x interface was also observed as a severe drawback to forming an ideal heterojunction. Oxygen vacancies in the SnO2-x surface, which act as hydrogen bonding sites for FA cations, induced withdrawal of FA cations, which was revealed by X-ray photoelectron spectroscopy (XPS) measurements. Inspired by this phenomenon, we fabricated a SnO2-x layer with reduced oxygen vacancies by using oxidized black phosphorus quantum dots (O-BPs). The multiple P=O bonds of O-BPs effectively assisted the formation of a SnO2-x layer with minimal oxygen vacancies. After P=O passivation, most of the detrimental effects were mitigated, showing highly stable α-FAPbI3 crystal structures. Consequently, we achieved a maximum PCE of 23.43% with enhanced thermal and operational stability.

Rapid and deep photocatalytic degradation of polyvinyl alcohol by black phosphorus quantum dot sensitized g-C3N4

To address the pollution caused by polyvinyl alcohol (PVA) waste, a composite photocatalyst is developed by sensitizing g-C3N4 with black phosphorus quantum dots (BPQDs) using a simple mechanical stirring method. Both g-C3N4 and BPQDs are inorganic nonmetallic semiconductors with well-matched band positions, facilitating efficient photoinduced charge transfer. The periodic table’s adjacent relationship between C, N and P elements allows easy formation of P-N or P-C bonds by replacing C or N atoms with P atoms. The resulting composite shows uniform decoration of two-dimensional layered g-C3N4 with BPQDs with an average size of 2.2 nm. Under solar light simulator irradiation for 20 min, the composite photocatalyst exhibits significantly enhanced photocatalytic activity, with PVA degradation efficiency increasing from 27.1% (pure g-C3N4) to 85.9%. Experimental results and density functional theoretical calculations suggest the formation of a Z-scheme route at the g-C3N4/BPQDs interface. This facilitates photoinduced electron transfer from g-C3N4 to BPQDs, leading to improved carrier production and separation, reduced charge-transfer resistance, and accelerated PVA degradation. The proposed composite photocatalyst holds promise for addressing PVA pollution and improving environmental sustainability.

Black phosphorus quantum dots camouflaged with platelet-osteosarcoma hybrid membrane and doxorubicin for combined therapy of osteosarcoma

BackgroundOsteosarcoma (OS) is the most prevalent primary malignant bone tumor. However, single-agent chemotherapy exhibits limited efficacy against OS and often encounters tumor resistance. Therefore, we designed and constructed an integrated treatment strategy of photothermal therapy (PTT) combined with chemotherapy and used a surface-encapsulated platelet-osteosarcoma hybrid membrane (OPM) that enhances circulation time and enables OS-specific targeting.ResultsThe OPM functions as a shell structure, encapsulating multiple drug-loaded nanocores (BPQDs-DOX) and controlling the release rate of doxorubicin (DOX). Moreover, near-infrared light irradiation accelerates the release of DOX, thereby extending circulation time and enabling photostimulation-responsive release. The OPM encapsulation system improves the stability of BPQDs, enhances their photothermal conversion efficiency, and augments PTT efficacy. In vitro and ex vivo experiments demonstrate that BPQDs-DOX@OPM effectively delivers drugs to tumor sites with prolonged circulation time and specific targeting, resulting in superior anti-tumor activity compared to single-agent chemotherapy. Furthermore, these experiments confirm the favorable biosafety profile of BPQDs-DOX@OPM.ConclusionsCompared to single-agent chemotherapy, the combined therapy using BPQDs-DOX@OPM offers prolonged circulation time, targeted drug delivery, enhanced anti-tumor activity, and high biosafety, thereby introducing a novel approach for the clinical treatment of OS.

The Addition of an Ultra-small Amount of Black Phosphorous Quantum Dots Endow Self-healing Polyurethane with a Biomimetic Intelligent Response.

This study explores new applications of black phosphorus quantum dots by adding them to self-healing material systems for the first time. Self-healing polyurethane with an ultra-small amount of black phosphorus quantum dots has biomimetic intelligent responsiveness and achieves balance between its mechanical and self-healing properties. By adding 0.0001 wt% black phosphorus quantum dots to self-healing polyurethane, the fracture strength of the material increases from 3.0 to 12.3MPa, and the elongation at break also increases from 750 to 860%. Meanwhile, the self-healing efficiency remains at 98%. The addition of black phosphorus quantum dots significantly improves the deformation recovery ability of the composite materials and transforms the surface of self-healing polyurethane from hydrophilic to hydrophobic, making it suitable for applications in fields such as electronic skin and flexible wearable devices. This study provides a simple and feasible strategy for endowing self-healing materials with biomimetic intelligent responsiveness using a small amount of black phosphorus quantum dots. This article is protected by copyright. All rights reserved.

An "on-off-on" electrochemiluminescence aptasensor based on a self-enhanced luminophore for ochratoxin A detection.

A highly selective and sensitive "on-off-on" electrochemiluminescence (ECL) aptasensor based on a self-enhanced luminophore was developed for the detection of ochratoxin A (OTA). Specifically, polyethyleneimine functionalized multi-walled carbon nanotubes decorated with gold nanoparticles (AuNPs-PEI-MWCNTs) were used as the electrode matrix to accelerate electron transfer and provide a favorable microenvironment for self-enhanced luminophore loading and ECL signal enhancement. In addition, black phosphorus quantum dots (BPQDs) were used as co-reactants of the ECL reagent tris (2,2'-bipyridyl) ruthenium(II) (Ru(bpy)32+) in ECL experiments, and the reaction mechanism was investigated. The self-enhanced luminophore Ru@SiO2-BPQDs was obtained by encapsulating Ru(bpy)32+ in silica (SiO2) nanoparticles and then combining it with BPQDs through electrostatic interaction. In conventional ECL systems, the emitter and its co-reactants reacted via the inter-nanoparticle pathway, leading tolong distance electron transfer. However, the electron transfer distance in the self-enhanced luminophore was significantly shortened due to the intra-nanoparticle electron transfer pathway because BPQDs and oxidized Ru(bpy)32+ were bound within one nanoparticle, thereby improving ECL efficiency to achieve the first "switch-on" state. Then, the luminophore was quenched using ferrocenes (Fc) modified on anaptamer to achieve the "switch-off" state. Finally, OTA was specifically identified by the adapter, causing Fc to be released from the sensor interface, restoring the ECL intensity to achieve the second "switch-on" state. Under optimal conditions, the aptasensor exhibited good sensitivity, stability, and reproducibility, with a linear detection range from 0.1 to 320ng/mL and a detection limit of 0.03ng/mL. The novel ECL aptasensor provided a common analytical tool for the detection of mycotoxins and other small molecules.