Synthesis and Evaluation of PEG-PR for Water Flux Correction in an In Situ Rat Perfusion Model.

Phenol red (PR) is a widely used marker for water flux correction in studies of in situ perfusion, in which intestinal absorption usually leads to the underestimation of results. In this paper, we propose a novel marker polyethylene glycol (PEG)-PR (i.e., PR modified by PEGylation) with less permeability and evaluate its application in an in situ perfusion model in rats. PEG-PR was synthesized by the chemical conjunction of polyethylene glycol-4k/5k (PEG-4k/5k) and PR. The synthesized PEG-PR was then characterized using 1H-NMR, 13C-NMR, ultraviolet (UV), X-ray diffraction (XRD), and differential scanning calorimetry (DSC) analyses. The low permeability of PEG-PR was assessed using everted gut sac (EGS) methods. The apparent permeability coefficients (Papp, 3-8 × 10-7 cm/s) of PEG4k/5k-PR exhibited a nearly 15-fold reduction compared to that of PR. The different concentrations of PEG4k/5k-PR did not contribute to the Papp value or cumulative permeable percentage (about 0.02-0.06%). Furthermore, the larger molecular weight due to PEGylation (PEG5k-PR) enhanced the nonabsorbable effect. To evaluate the potential application of the novel marker, atenolol, ketoprofen, and metoprolol, which represent various biopharmaceutics classification system (BCS) classes, were selected as model drugs for the recirculation perfusion method. The water flux corrected by PEG4k/5k-PR reflected the accuracy due to the nonabsorbable effect, while the effective intestinal membrane permeability (Peff) of atenolol corrected by PEG4k/5k-PR showed a statistically significant increase (p < 0.05) in different intestinal segments. In conclusion, PEG-PR is a promising marker for the permeability estimation when using the in situ perfusion model in rats.

Tumor Microenvironment Stimuli-Responsive Polymeric Prodrug Micelles for Improved Cancer Therapy.

PURPOSE: The discovery of nano drug delivery system has rendered a great hope for improving cancer therapy. However, there are some inevitable obstacles that constrain its development, such as the physical and biological barriers, the toxicity of carrier materials and the physiological toxicity of drugs. Here, we report a polymeric prodrug micelle (PPM) with pH/redox dual-sensitivity, which was prepared using methoxy poly (ethylene glycol) (mPEG) with favorable biosafety to improve cancer therapy. METHOD: The tumor microenvironment stimuli-responsive PPMs were prepared and characterized in vitro and in vivo. RESULTS: Our data displayed that the PPMs with excellent biocompatibility exhibited the stimuli-responsive drug release behavior under the microenvironment of cancer cells, superior cellular internalization and lower cytotoxicity. A new method to control drug release behavior was proposed by comparing the release behavior of PPMs formed by PEG of different molecular weight. Furthermore, the fabricated PPMs exhibited the "oral-like" blood concentration curve, improved biodistribution, reduced tissue toxicity and excellent antitumor efficiency in vivo. Consistently, these results indicated that PPMs improved chemotherapeutic efficiency and reduced side effects of the model drug doxorubicin (DOX). CONCLUSION: The prepared pH/redox dual-sensitive PPM enhanced the chemotherapy effect on the tumor site while reducing the physiological toxicity of DOX. Graphical Abstract.

The impact of anionic polyacrylamide (APAM) on ultrafiltration efficiency in flocculation-ultrafiltration process.

With the purpose of improving the ultrafiltration (UF) efficiency, anionic polyacrylamide (APAM) has been used as a coagulant aid in the flocculation-UF process. In this study, the impact of APAM on UF efficiency has been investigated with regard to membrane fouling, membrane cleaning and effluent quality. The results indicated that the optimal dosage of APAM had positive impacts on membrane fouling control, membrane cleaning and effluent quality. According to the flux decline curve, scanning electron microscopy and contact angle characterization, the optimal dosage of APAM was determined to be 0.1 mg/L coupled with 2 mg/L (as Al3+) poly-aluminium chloride. Under this optimal condition, membrane fouling can be mitigated because of the formation of a porous and hydrophilic fouling layer. APAM in the fouling layer can improve the chemical cleaning efficiency of 0.5% NaOH due to the disintegration of the fouling layer when APAM is dissolved under strong alkaline conditions. Furthermore, with the addition of APAM in the flocculation-UF process, more active adsorption sites can be formed in the flocs as well as the membrane fouling layer, thus more antipyrine molecules in the raw water can be adsorbed and removed in the flocculation-UF process.

Removal mechanism of low-concentration Cr (VI) in a submerged membrane bioreactor activated sludge system.

Removal mechanism of low-concentration Cr (VI) (0.4 mg/L) was studied in a submerged membrane bioreactor (SMBR) activated sludge system. SMBR was operated with the synthetic wastewater containing 0.4 mg/L Cr (VI). Bio-removal and inactivation batch experiments were also carried out for studying the low-concentration Cr (VI) removal mechanism. SMBR activated sludge system recovered rapidly from the 0.4 mg/L Cr (VI) shock to achieve the excellent removal of chemical oxygen demand (COD) and NH4 (+)-N. Sulfuricurvum kujiense grew quickly in the bacterial community of activated sludge after Cr (VI) addition. Cr (VI) was mainly removed by the adsorption of extracellular polymeric substances, probably in the form as R2(SOH(+))2 (.)CrO4 (2-). Only few of Cr (VI) was transferred into Cr (III) under aerobic condition. All the results indicated that the sulfur was probably involved in 0.4 mg/L Cr (VI) removal process in SMBR.

[Physicochemical Property of iRGD Peptide Modified Doxorubicin Loaded Liposome and Its Effect on Cancer Cell Growth].

OBJECTIVE: To determine the physicochemical properties of iRGD conjugated doxorubicin loaded liposome (iRGD-LP-DOX), and its effect on targeting and inhibiting growth of A549 cells. METHODS: Liposomes were observed under a transmission electron microscope. Release of doxorubicin from iRGD-LP-DOX was detected by the dialysis bag method. The efficiency of cellular uptake and tumor spheroids penetration on A549 cells in vitro was determined. The anti-proliferation efficiency of iRGD-LP-DOX was evaluated by MTT assay using IC50 (50% inhibition concentration). RESULTS: iRGD-LP-DOX was spherical in a uniform size. Free DOX was released by 100% in 5 h, while LP-DOX and iRGD-LP-DOX were released by about 40% in 48 h. A higher level of iRGD-LP-DOX uptaken by A549 was found compared with that of LP-DOX (P<0.01). Higher fluorescence intensity was detected with iRGD-LP-DOX than with LP-DOX in tumor spheroid. The MTT assay confirmed strong inhibitory effect of iRGD-LP-DOX (P<0.01). CONCLUSION: iRGD can enhance uptake of liposomes by A549 cells and inhibit the proliferation of tumor cells.

New insight into the effects of Ca(II) on cake layer structure in submerged membrane bioreactors.

The effects of Ca(II) on the structure of the cake layer in submerged membrane bioreactors (SMBRs) were investigated in this study. Three parallel laboratory-scale SMBRs were operated with synthetic municipal wastewater with three Ca(II) levels (82, 208 and 410 mg l(-1)). As the Ca(II) concentration increased, the sludge floc size increased and the molecular weight of the soluble microbial products (SMP) in the bulk liquid decreased. These observations were attributed to the neutralization and bridging function of Ca(II). Furthermore, Ca(II) addition did not change the thickness of the cake layer, but inhibited the deposition of other elements, such as Al, Si, Mg, and Fe. As a result of Ca(II) addition, the cake layer became less compact and more porous. The interspaces among the flocs in the cake layer helped to reduce the membrane fouling potential.

Effects of low-concentration Cr(VI) on the performance and the membrane fouling of a submerged membrane bioreactor in the treatment of municipal wastewater.

The effects of low-concentration Cr(VI) (0.4 mg l(-1)) on the performance of a submerged membrane bioreactor (SMBR) in the treatment of municipal wastewater, as well as membrane fouling were investigated. Compared with the SMBR for control municipal wastewater, the SMBR for Cr(VI)-containing municipal wastewater had a higher concentration of soluble microbial products (SMP) with lower molecular weights, and smaller sludge particle sizes. Furthermore, low-concentration Cr(VI) induced membrane fouling, especially irreversible membrane pore blocking, which markedly shortened the service life of the membrane.

Sewer sediment adhesion degeneration and gelatinous biopolymer deconstruction by structural cation chelation and alkaline macromolecule hydrolysis for improving hydraulic erosion.

Sediment siltation has been regarded as the serious challenge in sewer system, which dominantly root in the gelatinous extracellular polymeric substance (EPS) structure and cohesive ability. Considering the crucial roles of divalent cation bridging and macromolecular biopolymer winding in sediment EPS formation and adhesive behavior, an innovative combination strategy of sodium pyrophosphate (SP)-mediated divalent cation chelation and alkaline biopolymer hydrolysis was developed to degenerate sediment adhesion. At the SP dosage of 0.25 g/g TS and the alkaline pH 12, the SP + pH 12 treatment triggered structural transformation of aromatic proteins (α-helix to ß-turn) and functional group shifts of macromolecular biopolymers. In this case, the deconstruction and outward dissolution of gelatinous biopolymers were achievable, including proteins (tyrosine-like proteins, tryptophan-like proteins), humic acids, fulvic acids, polysaccharides and various soluble microbial products. These were identified as the major driving forces for sediment EPS matrix disintegration and bio-aggregation deflocculation. The extraction EPS content was obviously increased by 18.88 mg COD/g TS. The sediment adhesion was sensitive to EPS matrix damage and gelatinous biopolymer deconstruction, leading to considerable average adhesion degeneration to 0.98 nN with reduction rate of 78.32%. As such, the sediments could be disrupted into dispersive fragments with increased surface electronegativity and electric repulsion (up to -45.6 mV), thereby the sediment resistance to hydraulic erosion was impaired, providing feasibility for in-situ sediment floating and removal by gravity sewage flow in sewer.

Continuation of a cleaning process: Application of MNBs-coagulation process to mitigate ultrafiltration membrane fouling.

The MNBs-coagulation process as a novel and cleaning enhanced coagulation process has been demonstrated to enhance the removal efficiency of hydrophilic organics. In this study, while continuing the concept of cleaning production, the MNBs-coagulation process was first applied to the ultrafiltration process and was expected to alleviate the ultrafiltration membrane fouling. This study investigated the effect of the involvement of MNBs in coagulation-ultrafiltration process (the MC-UF process) on the fouling behaviour of ultrafiltration membrane based on the calculation of membrane resistance distribution and the fitting of membrane fouling model. In addition, the NOM removal efficiency, floc characteristics analysis and membrane hydrophilicity analysis were used to illustrate the mechanism of mitigating ultrafiltration mebrane fouling by the MC-UF process. The experimental results showed that the involvement of MNBs in the coagulation-ultrafiltration process was able to reduce the irreversible fouling and TMP by 43.1 % and 41.6 % respectively. This phenomenon could be attributed to the involvement of MNBs in the coagulation process to improve the removal efficiency of hydrophilic organics and to enhance the characteristics of flocs, thus reducing the possibility of hydrophilic organics and broken flocs entering and blocking the membrane pores. In addition, the FT-IR spectral changes before and after the floc breakage were analyzed by 2D-COS technique in this study, and it was found for the first time that the participation of MNBs in the coagulation process could change the sequence of functional group transformation within the floc, and promote the generation of hydrogen bonds between flocs by hindering the generation of hydroxyl groups (-OH), and improve the shear resistance and regrowth capacity of flocs while reducing the possibility of broken flocs entering and blocking membrane pores. In summary, the MC-UF process proposed in this study can significantly mitigate ultrafiltration membrane fouling while meeting cleaning production, providing theoretical support for the application of the process to practical engineering.

Mechanistic insight into the impact of polystyrene microparticle on submerged plant during asexual propagules germination to seedling: Internalization in functional organs and alterations of physiological phenotypes.

Asexual reproduction is one of the most important propagations in aquatic plants. However, there is a lack of information about the growth-limiting mechanisms induced by microplastics on the submerged plant during asexual propagule germination to seedling. Hence, we investigated the effects of two sizes (2 µm, 0.2 µm) and three concentrations (0.5 mg/L, 5 mg/L, and 50 mg/L) of polystyrene microplastics (PSMPs) on Potamogeton crispus turion germination and seedling growth. Both PSMPs sizes were found in P. crispus seedling tissues. Metabolic profile alterations were observed in leaves, particularly affecting secondary metabolic pathways and ATP-binding cassette transporters. Metal elements are indispensable cofactors for photosynthesis; however, alterations in the metabolic profile led to varying degrees of reduced concentrations in magnesium, iron, copper, and zinc within P. crispus. Therefore, the maximum quantum yield of photosystem II significantly decreased in all concentrations with 0.2 µm-PSMPs, and at 50 mg/L with 2 µm-PSMPs. These findings reveal that internalization of microplastics, nutrient absorption inhibition, and metabolic changes contribute to the negative impact on P. crispus seedlings.

Uptake and effect of carboxyl-modified polystyrene microplastics on cotton plants.

Microplastics (MPs) have emerged as a significant global environmental concern, particularly within agricultural soil systems. The extensive use of plastic film mulching in cotton cultivation has led to the alarming presence of MP pollution in cotton fields. However, the uptake and effects of MPs on the growth of cotton plants are poorly understood. In this study, we conducted a comprehensive analysis of hydroponically cultured cotton seedlings at the phenotypic, transcriptional, and metabolic levels after exposure to carboxyl-modified polystyrene microplastics (PS-COOH). Treatment with three concentrations of PS-COOH (100, 300, and 500 mg/L) resulted in notable growth inhibition of treated plants and exhibited a dose-dependent effect. And, PS-COOH can invade cotton roots and be absorbed through the intercellular spaces via apoplastic uptake, with accumulation commensurate with treatment duration. Transcriptomic analysis showed significant up-regulation of genes associated with antioxidant activity in response to 300 mg/L PS-COOH treatment, suggesting the induction of oxidative stress. In addition, the PS-COOH treatment activated the phenylpropanoid biosynthesis pathway, leading to lignin and flavonoid accumulation, and altered sucrose catabolism. These findings illustrate the absorption and effects of MPs on cotton seedlings and offer valuable insights into the potential toxicity of MPs to plants in soil mulched with plastic film.

Gas permeable membrane electrode assembly with in situ utilization of authigenic acid and base for transmembrane electro-chemisorption to enhance ammonia recovery from wastewater.

Ammonia recovery from wastewater is of great significance for aquatic ecology safety, human health and carbon emissions reduction. Electrochemical methods have gained increasing attention since the authigenic base and acid of electrochemical systems can be used as stripper and absorbent for transmembrane chemisorption of ammonia, respectively. However, the separation of electrodes and gas permeable membrane (GPM) significantly restricts the ammonia transfer-transformation process and the authigenic acid-base utilization. To break the restrictions, this study developed a gas permeable membrane electrode assembly (GPMEA), which innovatively integrated anode and cathode on each side of GPM through easy phase inversion of polyvinylidene fluoride binder, respectively. With the GPMEA assembled in a stacked transmembrane electro-chemisorption (sTMECS) system, in situ utilization of authigenic acid and base for transmembrane electro-chemisorption of ammonia was achieved to enhance the ammonia recovery from wastewater. At current density of 60 A/m2, the transmembrane ammonia flux of the GPMEA was 693.0 ± 15.0 g N/(m2·d), which was 86 % and 28 % higher than those of separate GPM and membrane cathode, respectively. The specific energy consumption of the GPMEA was 9.7∼16.1 kWh/kg N, which were about 50 % and 25 % lower than that of separate GPM and membrane cathode, respectively. Moreover, the application of GPMEA in the ammonia recovery from wastewater is easy to scale up in the sTMECS system. Accordingly, with the features of excellent performance, energy saving and easy scale-up, the GPMEA showed good prospects in electrochemical ammonia recovery from wastewater.

Micro-flow cell washing technique combined with single-cell Raman spectroscopy for rapid and automatic antimicrobial susceptibility test of pathogen in urine.

Facing the rapid spread of antimicrobial resistance, methods based on single-cell Raman spectroscopy have proven their advances in reducing the turn-around time (TAT) of antimicrobial susceptibility tests (AST). However, the Raman-based methods are still hindered by the prolonged centrifugal cell washing procedure, which may require complex labor operation and induce high mechanical stress, resulting in a pretreatment time of over 1 h as well as a high cell-loss probability. In this study, we developed a micro-flow cell washing device and corresponding Raman-compatible washing chips, which were able to automatically remove the impurities in the samples, retain the bacterial cell and perform Raman spectra acquisition in situ. Results of washing the 5- and 10-µm polymethyl methacrylate (PMMA) microspheres showed that the novel technique achieved a successful removal of 99 % impurity and an 80 % particle retention rate after 6 to 10 cycles of washing. The micro-flow cell washing technique could complete the pretreatment for urine samples in a 96-well plate within 10 min, only taking 15 % of the handling time required by centrifugation. The AST profiles of urine sample spiked with E. coli 25922, E. faecalis 29212, and S. aureus 29213 obtained by the proposed Raman-based approach were found to be 100 % consistent with the results from broth micro-dilution while reducing the TAT to 3 h from several days which is required by the latter. Our study has demonstrated the micro-flow cell washing technique is a reliable, fast and compatible approach to replace centrifuge washing for sample pretreatment of Raman-AST and could be readily applied in clinical scenarios.

A stacked transmembrane electro-chemisorption system connected by hydrophobic gas permeable membranes for on-site utilization of authigenic acid and base to enhance ammonia recovery from wastewater.

The ammonia recovery from wastewater via electrochemical technologies represents a promising way for wastewater treatment, resource recovery, and carbon emissions reduction. However, chemicals consumption and reactors scalability of the existing electrochemical systems have become the key challenges for their development and application. In this study, a stacked transmembrane electro-chemisorption (sTMECS) system was developed to utilize authigenic acid and base on site for enhancing ammonia recovery from wastewater. The easily scaled up system was achieved via innovatively connecting the cathode chamber in a unit with the anode chamber in the adjacent unit by a hydrophobic gas permeable membrane (GPM). Thus, authigenic base at cathodes and authigenic acid at anodes could be utilized as stripper and absorbent on site to enhance the transmembrane chemisorption of ammonia. Continuous power supply, reducing the distances of electrodes to GPM and moderate aeration of the catholyte could promote ammonia recovery. Applied to the ammonia recovery from the simulated urine, the sTMECS under the current density 62.5 A/cm2 with a catholyte aeration rate of 3.2 L/(L⋅min) for operation time 4 h showed the transmembrane ammonia flux of 26.00 g N/(m2·h) and the system energy consumption of 10.5 kWh/kg N. Accordingly, the developed sTMECS system with chemicals saving, easy scale-up and excellent performance shows good prospects in recovering ammonia from wastewater.

Dual targetable drug delivery system based on cell membrane camouflaged liposome for enhanced tumor targeting and improved anti-tumor efficiency.

Receptor and ligand binding mediated targeted drug delivery systems (DDS) sometimes fail to target to tumor sites, and cancer cell membrane (CCM) coating can overcome the dilemma of immune clearance and nonspecific binding of DDS in vivo. In order to enhance the targeting ability and improve the anti-tumor effect, a dual targeting DDS was established based on U87MG CCM mediated homologous targeting and cyclic peptide RGD mediated active targeting. The DDS was prepared by coating RGD doped CCM onto doxorubicin (DOX) loaded liposomes. The homologous and active dual targeting ability endowed the DDS (RGD-CCM-LP-DOX) exhibited superior cancer cell affinity, improved tissue distribution and enhanced anti-tumor effects. In vivo pharmacodynamic studies revealed that RGD-CCM-LP-DOX exhibited superior therapeutic effect compared with homologous targeting CCM-LP-DOX and non-targetable LP-DOX injection. H&E staining, Ki 67 staining and TUNEL staining confirmed that RGD-CCM-LP-DOX not only increased anti-tumor efficacy, but also reduced tissue toxicity by changing the distribution in vivo. The experimental results showed that the RGD doped CCM camouflaged liposome DDS is a better choice for chemotherapeutics delivery.

Cancer cell membrane coated PLGA nanoparticles as biomimetic drug delivery system for improved cancer therapy.

Based on the immune escape and homologous adhesion ability of cancer cells, a drug delivery system (DDS) could overcome the dilemma of immune clearance and non-specific binding by coating the cancer cell membrane (CCM). In this study, a biomimetic DDS based on CCM and poly lactic acid-glycolic acid (PLGA) nanoparticles was successfully constructed for tumor active and homologous targeting therapy. The doped CCM on the surface of the nanoparticle enabled the DDS to achieve immune escape and had an affinity for tumor tissues. The cellular uptake and in vivo distribution tests showed a superior cellular affinity of CCM coated PLGA nanoparticles (CCMNPs) than that of PLGA nanoparticles (PLGANPs). All of those results proved that CCMNPs endowed with drug-loaded nanoparticles had the abilities of immune escape and homologous targeting through the biological functional proteins retained on the coated CCM. In addition, the tumor inhibition rate of CCMNPs in tumor-bearing nude mice was 1.3 and 2.0-fold compared to PLGANPs and PTX injection, which showed the capacity to efficiently and accurately deliver drugs to cancer sites improved the therapeutic effect of tumor and achieved accurately targeted therapy.

Osmotic stress-induced lignin synthesis is regulated at multiple levels in alfalfa (Medicago sativa L.).

Alfalfa is an important forage crop. Yield and quality are frequently threatened by extreme environments such as drought and salt stress. As a component of the cell wall, lignin plays an important role in the abiotic stress response, the mechanisms of which have not been well clarified. In this study, we combined physiological, transcriptional, and metabolic analyses to reveal the changes in lignin content in alfalfa under mannitol-induced osmotic stress. Osmotic stress enhanced lignin accumulation by increasing G and S units, which was associated with increases in enzyme activities and decreases in 8 intermediate metabolites. Upon combined analysis of the transcriptome and metabolome, we identified five key structural genes and several coexpressed transcription factors, such as MYB and WRKY, which may play a core role in regulating lignin content and composition under osmotic stress. In addition, lignin synthesis was positively regulated by ABA but negatively regulated by ethylene under osmotic stress. These results provide new insight into the regulatory mechanism of lignin synthesis under abiotic stress.

Brain default-mode network abnormalities in hepatic encephalopathy: a resting-state functional MRI study.

Many neuroimaging investigations focus on hepatic encephalopathy (HE); however, few investigate default-mode network (DMN) in the patients with HE and its underlying physiological relevance using resting-state fMRI. In this study, independent component analysis was used to retrieve components representing the DMN of patients with HE (n = 14) and healthy volunteers (n = 14). Four patients were excluded because of head motion (n = 3) and the artifact from the artificial tooth (n = 1). Comparison results between the two groups revealed significantly reduced functional connectivity in the right middle frontal gyrus and left posterior cingulate cortex in the HE patients. A statistical t-map from the comparison of venous blood ammonia levels and the z-scores of the DMN obtained from independent component analysis was computed in the HE group, which showed negative correlation with the changes in left angular gyrus. In conclusions, resting-state fMRI can be used to examine DMN changes in HE patients. Reduced functional connectivity in the right middle frontal gyrus and left posterior cingulate cortex consisting of the DMN and negative correlation between the functional connectivity changes in left AG and the venous blood ammonia levels support the notion of damages in functional organization of the central nervous system in HE patients.

Influence and mechanism of N-(3-oxooxtanoyl)-L-homoserine lactone (C8-oxo-HSL) on biofilm behaviors at early stage.

N-acyl-homoserines quenching, enzymatic quenching of bacterial quorum sensing, has recently applied to mitigate biofilm in membrane bioreactor. However, the effect of AHLs on the behavior of biofilm formation is still sparse. In this study, Pseudomonas aeruginosa biofilm was formed on ultra-filtration membrane under a series of N-(3-oxooxtanoyl)-L-homoserine lactone (Cs-oxo-HSL) concentrations. Diffusing C8-oxo-HSL increased the growth rate of cells on biofilm where the concentration of C8-oxo-HSL was over 10(-7) g/L. The C8-oxo-HSL gradient had no observable influence on cell density and extracellular polymeric substances of biofilm with over 10(-7) g/L C8-oxo-HSL. Surprisingly, 10(-11)-10(-8) g/L of C8-oxo-HSL had no effect on cell growth in liquid culture. The cell analysis demonstrated that the quorum sensing system might enhance the growth of neighboring cells in contact with surfaces into biofilm and may influence the structure and organization of biofilm.

Poly-l-lysine derivative-coated black phosphorus as a nanoplatform for photothermal chemotherapy to enhance anti-tumor efficiency.

Severe systemic toxicity and side effects are major obstacles to the success of chemotherapy for tumors. Regardless of the choice of chemotherapy drugs, the safety of drug delivery materials is crucial, and therefore, there have been various efforts to improve the therapeutic effect and the biological safety of drug delivery systems (DDSs). In this study, a dual stimulus-response DDS (PLL-SS@DOX-BP) was constructed based on the biomaterials of black phosphorus (BP) nanosheets and poly-l-lysine (PLL) to enhance the treatment of doxorubicin hydrochloride (DOX) for breast cancer. The PLL derivative was nano-coated on the surface of drug-loaded BP nanosheets, and it prevented premature leakage of the drug and maintained the stability of the DDS. The introduced disulfide bonds and photothermal agent BP enabled the redox and near-infrared responsive drug release of the DDS, and the coated PLL derivative on the nanocarrier decreased premature leakage of the drug before the DDS reached the tumor tissues. The in vitro and in vivo experiments showed that the combination of biomaterial (PLL) and photothermal material (BP nanosheets) exhibited excellent biological safety and remarkable drug delivery capacity. Moreover, the pharmacodynamic studies indicated that PLL-SS@DOX-BP is a powerful vehicle for photothermal therapy in combination with chemotherapy. Compared with chemotherapy alone, the developed DDS displayed enhanced anti-tumor efficiency with decreased systemic toxicity, and thus, it has the potential to be a promising anti-tumor treatment strategy.