Chemical Coupling Research Articles

The mimicked cell penetration peptides of chitosan derivates with low molecular weight for transdermal enhancement studies

The biomimetic chitosan derivatives synthesized by chemical coupling of L-arginine onto chitosan with low molecular weight, named Arg-CS, which was prepared by mimicking the arginine-rich peptides, to achieve the permeability performance of Cell-penetrating peptides (CPPs). The physicochemical properties of the Arg-CSs were characterized via Attenuated total reflection Fourier transform infrared (ATR-FTIR) and 1H-nuclear magnetic resonance spectroscopy (1H NMR), and high-performance liquid chromatography (HPLC). The thermal stability of Arg-CS was improved by approximately 80 °C, compared to the pure chitosan. The maximum cumulative amounts of aspirin for Arg-CS 4.7 k, Arg-CS 5.2 k, and Arg-CS 6.3 k were 32.85 µg/cm2, 22.98 µg/cm2, and 17.51 µg/cm2 at 8 h, respectively, presenting a phenomenon of increasing of aspirin permeation with decreasing molecular weight of Arg-CS. Arg-CS with low molecular weight was more conducive to improve the penetration of aspirin by changing the secondary structure of keratin from β-sheets to random coil. The molecular docking also suggested that Arg-CS had stronger affinity to keratin by strong hydrogen bond interactions. These results indicated that the nonirritant and thermally stable Arg-CS with lower molecular weight can be used to enhance the permeation of aspirin and applied in the field of transdermal drug delivery.

Development of Conjugated Kefiran-Chondroitin Sulphate Cryogels with Enhanced Properties for Biomedical Applications.

Hydrogels based on natural polysaccharides can have unique properties and be tailored for several applications, which may be mainly limited by the fragile structure and weak mechanical properties of this type of system. We successfully prepared cryogels made of newly synthesized kefiran exopolysaccharide-chondroitin sulfate (CS) conjugate via carbodiimide-mediated coupling to overcome these drawbacks. The freeze-thawing procedure of cryogel preparation followed by lyophilization is a promising route to fabricate polymer-based scaffolds with countless and valuable biomedical applications. The novel graft macromolecular compound (kefiran-CS conjugate) was characterized through 1H-NMR and FTIR spectroscopy-which confirmed the structure of the conjugate, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA)-which mirrored good thermal stability (degradation temperature of about 215 °C) and, finally, gel permeation chromatography-size exclusion chromatography (GPC-SEC)-which proved an increased molecular weight due to chemical coupling of kefiran with CS. At the same time, the corresponding cryogels physically crosslinked after the freeze-thawing procedure were investigated by scanning electron microscopy (SEM), Micro-CT, and dynamic rheology. The results revealed a prevalent contribution of elastic/storage component to the viscoelastic behavior of cryogels in swollen state, a micromorphology with micrometer-sized open pores fully interconnected, and high porosity (ca. 90%) observed for freeze-dried cryogels. Furthermore, the metabolic activity and proliferation of human adipose stem cells (hASCs), when cultured onto the developed kefiran-CS cryogel, was maintained at a satisfactory level over 72 h. Based on the results obtained, it can be inferred that the newly freeze-dried kefiran-CS cryogels possess a host of unique properties that render them highly suitable for use in tissue engineering, regenerative medicine, drug delivery, and other biomedical applications where robust mechanical properties and biocompatibility are crucial.

Numerical modeling and verification of reactive projectile impacting plate

The penetration of reactive projectile into target is an extremely complex thermomechanical coupling process, and most of the researches reveal this coupling mechanism by means of experiments. In this paper, based on the finite element simulation software ANSYS/LS-DYNA, using IGNITION_ANG_GROWTH state equation and Null constitutive model, the process of reactive projectile penetrating target is numerically modeled, and the numerical simulation model is verified by ballistic impact test. The test results are in good agreement with the simulation results. Further, according to this numerical simulation model, the ballistic limit of reactive projectile penetrating target is studied. The results show that the IGNITION_ANG_GROWTH state equation and Null Constitutive model can be used to calculate the mechanical and chemical coupling responses of the reactive projectile in the process of penetration plate effectively based on the SPH algorithm. This provides a new method to study the reactive projectile penetration-explosion coupling process.

High pressure oxidation of NH[formula omitted]/[formula omitted]-heptane mixtures

Oxidation of NH3/n-heptane mixtures at pressures up to 100 atm and temperatures of 400–900 K was characterized experimentally in a laminar flow reactor and a jet-stirred reactor. A detailed chemical kinetic model was developed, updating the hydrogen and amine subsets and introducing a subset for the chemical coupling with emphasis on the NH2+n-heptane reaction. The kinetic model provided a good prediction of the ignition delay times measured in a rapid compression machine by Yu et al. (Combust. Flame 217 (2020) 2–11) as well as the high pressure experimental data obtained in the present work. The results show that it is important to include updated rate constants for NH2 + HO2 and NH2 + n-C7H16 to obtain reliable predictions for ignition and oxidation of NH3/n-heptane mixtures at high pressure. The effectiveness of implementing analogy rules for determining the rate constant of the key reaction NH2 + n-C7H16 was confirmed by the observed results.

Atom-triggered epitaxial growth of Bi-based perovskite heterojunctions for promoting interfacial charge transfer

The construction of high-quality heterojunction with staggered band structure and close-contact interface, to satisfy both the thermodynamic and dynamic prerequisites of charge transfer, is the key to improve the charge separation of halide perovskites. The in situ growth of perovskite heterojunction via cosharing atoms provides an appealing solution to tackle this dilemma, but it remains a big challenge owing to the lack of appropriate precursors. Here, we design a novel visible-light responsive CoxBi2−xO2CO3 nanosheet, and use it as self-template to epitaxially grow Cs3Bi2Br9 nanosheet. It is revealed that close-contact 2D/2D heterointerfaces with strong chemical and electronic coupling are built via Bi atom bridge. Moreover, incorporating Co3+ into Bi2O2CO3 plays critical roles in heterojunction growth by regulating both the electronic structure and growth dynamics of Cs3Bi2Br9. Triggered by the effect of Co and the matched Bi lattice with Cs3Bi2Br9, the CoxBi2−xO2CO3/Cs3Bi2Br9 heterojunction can drive the fast Z-scheme transfer and separation of photoexcited charge carriers.

Unique Fluorescent Protein-Encoded Microbeads with Supramaximal Encoding Capacity and High Sensitivity for Multiplex Bioassays.

Fluorescence-encoded microbeads (FEBs) have been widely used as a critical component in multiplexed biomolecular assays. Here, we propose a simple, sustainable, low-cost, and safe strategy for preparing FEBs by assembling fluorescent proteins (FPs) onto magnetic microbeads (MBs) via chemical coupling. Combining the type of FP, the concentration of FP, and the size of the magnetic microbeads as encoding elements, an ultralarge encoding capacity with 506 barcodes was obtained. We demonstrate that the FP-based FEBs have good stability during long-term storage and tolerate the use of an organic solution. Multiplex detection of femtomolar ssDNA molecules was achieved via flow cytometry, and the detection procedure is simple and fast because it does not require amplification and washing strategies. The advantages of this advanced method for multiplex detections including high sensitivity, specificity, accuracy, repeatability, rapidity, and cost-effectiveness show a broad application prospect in basic and applied research fields such as disease diagnosis, food safety, environmental protection, proteomics, genomics, and drug screening.

N-doped carbon wrapped CoFe alloy nanoparticles with MoS2 nanosheets as electrocatalyst for hydrogen and oxygen evolution reactions

Developing efficient and cost-effective transition metal-based electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is crucial to generate clean and renewable hydrogen energy. The construction of hybrid catalysts with multiple active sites is an effective approach to promote catalytic performance. Herein, a molybdenum disulfide (MoS2)-based hybrid with N-doped carbon wrapped CoFe alloy (MoS2/CoFe@NC) was synthesized through a typical hydrothermal method. The MoS2/CoFe@NC exhibits excellent electrocatalytic performance with overpotentials of 172 mV for HER and 337 mV for OER at 10 mA cm−2, and long-term stability of 24-h electrolytic reaction in 1 M KOH solution. The chemical coupling between MoS2 and CoFe@NC provides improved electronic structures and more accessible active sites. The CoFe@NC substrate accelerates the charge transfer to MoS2 through a synergistic effect. This work demonstrates that the CoFe@NC is a promising substrate for depositing MoS2 nanosheets (NSs) to achieve excellent catalytic performance for both HER and OER.

The crystallinity of chemically bonded PA‐PTFE‐oil compounds by X‐ray diffraction and DSC

AbstractOne of the major shortcomings of compounding polyamide (PA), polytetrafluoroethylene (PTFE), and olefinic oils is the fact that they are incompatible. To overcome this issue, using energy radiation in the presence of oxygen leads to the breakage of the PTFE chain to generate hydrophilic functional groups (COF, COOH) and peroxy radicals. The created functional groups and radicals can be used to induce a chemical bond between PA and PTFE as well as between PTFE and olefinic oil molecules. In addition, the hardness of compounds significantly influences the application of materials as solid‐lubricant. It is well known that crystallinity affects the hardness of materials. In the presented study, the effects of the chemical bonding PA‐PTFE/PA‐PTFE‐oil on the crystallization behavior of various types of PA in chemically bonded PA‐PTFE‐oil‐chemically bonded compounds, which were prepared by reactive two‐step extrusion, were investigated via DSC and X‐ray diffraction. The crystallite size of PA46 and PA66 in PA‐PTFE‐chemically bonded (cb) compounds was significantly increased compared with pure PA. At the same time, the d‐spacings of the PA segment in PA‐PTFE compounds were significantly narrower. Due to the chemical coupling, the compounds showed a slight change in hardness compared with pure PA.

Nanoscale transition metal catalysts anchored on perovskite oxide enabling enhanced kinetics of lithium polysulfide redox in lithium-sulfur batteries

To obtain high-performance lithium-sulfur (Li-S) batteries, it is necessary to rationally design electrocatalytic materials that can promote efficient sulfur electrochemical reactions. Herein, the robust heterostructured material of nanoscale transition metal anchored on perovskite oxide was designed for efficient catalytic kinetics of the oxidation and reduction reactions of lithium polysulphide (LiPSs), and verified by density functional theory (DFT) calculations and experimental characterizations. Due to the strong interaction of nanoscale transition metals with LiPSs through chemical coupling, heterostructured materials (STO@M) (M = Fe, Ni, Cu) exhibit excellent catalytic activity for redox reactions of LiPSs. The bifunctional heterostructure material STO@Fe exhibits good rate performance and cycling stability as the cathode host, realizing a high-performance Li-S battery that can maintain stable cycling under rapid charge–discharge cycling. This study presents a novel approach to designing electrocatalytic materials for redox reactions of LiPSs, which promotes the development of fast charge–discharge Li-S batteries.

An empirical analysis of Delhi's air quality throughout different COVID-19 pandemic waves

Delhi was one of India's COVID-19 hotspots, with significant death rates during the year 2021. This study looked at the link between COVID-19 cases in Delhi, and key meteorological variables. The study found that COVID-19 cases during the second wave (P2-March- May 2021) were much higher than during the first wave (P1-Jan-Feb 2021) in Delhi. During P1 (Jan-Feb 2021) the mean PM2.5, PM10, NO2 and CO concentrations were greater than that of P2 (March-May 2021) while the reverse happened for SO2 and O3. Spearman correlation test indicated that COVID-19 cases maintained a significant positive correlation with the high temperature of P2 (March-May 2021) and high humidity of P1 (Jan-Feb 2021) in line with the accepted notion that COVID-19 transmitted favourably in hot and humid climates. The Multilayer perceptron (MLP) model indicated that COVID-19 spread was supported by air pollutants and climate variables like PM2.5, NO2, RH, and WS in P1(Jan-Feb 2021) and PM2.5 and O3 in P2 (March-May 2021). Owing to chemical coupling, across all six monitoring stations, O3 maintained an inverse relationship with NO2 throughout the COVID-19 phases in Delhi. The city dwellers had health risks also due to PM pollution at varying degrees, indicated by high hazard quotients (HQs), requiring lowering of air pollution concentrations on an urgent basis.

Plasma-Enhanced Chemical Looping Oxidative Coupling of Methane through Synergy between Metal-Loaded Dielectric Particles and Non-Thermal Plasma

A plasma–catalyst hybrid system has been developed for the direct conversion of methane to C2+ hydrocarbons in dielectric barrier discharge (DBD) plasma. TiO2 presented the highest C2+ yield of 11.63% among different dielectric materials when integrated with DBD plasma, which made us concentrate on the TiO2-based catalyst. It was demonstrated that MnTi catalyst showed the best methane coupling performance of 27.29% C2+ yield with 150 V applied voltage, without additional thermal input. The catalytic performance of MnTi catalyst under various operation parameters was further carried out, and different techniques, such as X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, and H2-temperature-programmed reduction were used to explore the effect of Mn loading on methane oxidative coupling (OCM) performance. The results showed that applied voltage and flow rate had a significant effect on methane activation. The dielectric particles of TiO2 loaded with Mn not only synergistically affected the coupling reaction, but also facilitated charge deposition to generate a strong local electric field to activate methane. The synergy effects boosted the OCM performance and the C2+ yield became 1.25 times higher than that of the undoped TiO2 under identical operating conditions in plasma, which was almost impossible to occur even at 850 °C on the MnTi catalyst in the absence of plasma. Moreover, the reaction activity of the catalyst was fully recovered by plasma regeneration at 300 °C and maintained its stability in for at least 30 consecutive cyclic redox tests. This work presents a new opportunity for efficient methane conversion to produce C2+ at low temperatures by plasma assistance.

Ultrasmall Enzyme-Powered Janus Nanomotor Working in Blood Circulation System.

Injectable chemically powered nanomotors may revolutionize biomedical technologies, but to date, it is a challenge for them to move autonomously in the blood circulation system and they are too large in size to break through the biological barriers therein. Herein, we report a general scalable colloidal chemistry synthesis approach for the fabrication of ultrasmall urease-powered Janus nanomotors (UPJNMs) that have a size (100-30 nm) meeting the requirement to break through the biological barriers in the blood circulation system and can efficiently move in body fluids with only endogenous urea as fuel. In our protocol, the two hemispheroid surfaces of eccentric Au-polystyrene nanoparticles are stepwise grafted with poly(ethylene glycol) brushes and ureases via selective etching and chemical coupling, respectively, forming the UPJNMs. The UPJNMs have lasting powerful mobility with ionic tolerance and positive chemotaxis, while they are able to be dispersed steadily and self-propelled in real body fluids, as well as demonstrate good biosafety and a long circulation time in the blood circulation system of mice. Thus, the as-prepared UPJNMs are promising as an active theranostics nanosystem for future biomedical applications.

Tailoring the phase transition from topological superconductor to trivial superconductor induced by magnetic textures of a spin chain on a p -wave superconductor

We theoretically investigate the phase transition from a nontrivial topological $p$-wave superconductor to a trivial $s$-wave-like superconducting phase through a gapless phase, driven by different magnetic textures as a one-dimensional spin-chain impurity, e.g., Bloch-type, in-plane, and out-of-plane N\'eel-type spin chains, etc. In our proposal, the chain of magnetic impurities is placed on a spin-triplet $p$-wave superconductor where we obtain numerically as well as analytically an effective $s$-wave-like pairing due to spin rotation, resulting in gradual destruction of the Majorana zero modes present in the topological superconducting phase. In particular, when the impurity spins are antiferromagnetically aligned, i.e., spiral wave vector ${G}_{\mathrm{s}}=\ensuremath{\pi}$, the system becomes an effective $s$-wave superconductor without Majorana zero modes in the local density of states. The Shiba bands, on the other hand, formed due to the overlapping of Yu-Shiba-Rusinov states play a crucial role in this topological to trivial superconductor phase transition, confirmed by the sign change in the minigap within the Shiba bands. We also characterize this topological phase transition via gap closing and winding number analysis. Moreover, interference of the Shiba bands exhibiting oscillatory behavior within the superconducting gap $\ensuremath{-}{\mathrm{\ensuremath{\Delta}}}_{p}$ to ${\mathrm{\ensuremath{\Delta}}}_{p}$, as a function of ${G}_{s}$, also reflects an important evidence for the formation of an effective $s$-wave pairing. Such oscillation is absent in the $p$-wave regime. We also analyze the case of two-dimensional $p$-wave superconductor hosting Majorana edge modes (in absence of any magnetic chain) and show that initially Majorana zero modes (in presence of one-dimensional magnetic chain) can hybridize with such Majorana edge modes. Interestingly, in the topological regime with a fixed ${G}_{s}$ value, the Mazorana zero modes survive at the ends of the magnetic chain even when the Majorana edge states disappear at some critical value of the chemical potential and exchange coupling strength.

Geraniol-Derived Monoterpenoid Glucosides from Rhodiola rosea: Resolving Structures by QM-HifSA Methodology.

Monoterpenoids are integral to the chemical composition of the widely used adaptogenic dietary supplement Rhodiola rosea. The present study expands the chemical space and stereochemical information about these taxon-specific constituents from the isolation and characterization of five geraniol-derived glucosides, 1-5. While 1 and 2 exhibited almost identical NMR spectra and shared the same 2D structure ascribed to the 4-hydroxygeraniolglucoside previously described as rosiridin, the NMR-based Mosher ester method revealed the enantiomeric nature of their aglycone moieties. This marks the first report of enantiomeric aglycones among geraniol derivatives. These findings also resolve the long-standing dispute regarding the absolute configuration of rosiridin and congeneric C-4 hydroxylated geraniols and may help explain incongruent bioactivity reports of R. rosea extract. Moreover, the three previously undescribed geranioloids 3-5 were fully characterized by extensive spectroscopic analysis. Quantum mechanics-driven 1H iterative functionalized spin analysis (QM-HifSA) was performed for all isolates and provides detailed NMR spin parameters, with adequate decimal place precision, which enable the distinction of such close congeners exhibiting near identical NMR spectra with high specificity. The outcomes also reinforce the importance of reporting chemical shifts and coupling constants with adequate decimal place precision as a means of achieving specificity and reproducibility in structural analysis.

Independent Innexin Radiation Shaped Signaling in Ctenophores.

Innexins facilitate cell-cell communication by forming gap junctions or nonjunctional hemichannels, which play important roles in metabolic, chemical, ionic, and electrical coupling. The lack of knowledge regarding the evolution and role of these channels in ctenophores (comb jellies), the likely sister group to the rest of animals, represents a substantial gap in our understanding of the evolution of intercellular communication in animals. Here, we identify and phylogenetically characterize the complete set of innexins of four ctenophores: Mnemiopsis leidyi, Hormiphora californensis, Pleurobrachia bachei, and Beroe ovata. Our phylogenetic analyses suggest that ctenophore innexins diversified independently from those of other animals and were established early in the emergence of ctenophores. We identified a four-innexin genomic cluster, which was present in the last common ancestor of these four species and has been largely maintained in these lineages. Evidence from correlated spatial and temporal gene expression of the M. leidyi innexin cluster suggests that this cluster has been maintained due to constraints related to gene regulation. We describe the basic electrophysiological properties of putative ctenophore hemichannels from muscle cells using intracellular recording techniques, showing substantial overlap with the properties of bilaterian innexin channels. Together, our results suggest that the last common ancestor of animals had gap junctional channels also capable of forming functional innexin hemichannels, and that innexin genes have independently evolved in major lineages throughout Metazoa.

Oxidation of Methane/n-Heptane Mixtures in a High-Pressure Flow Reactor

To evaluate the use of diesel as a pilot fuel in natural gas combustion in two-stroke maritime engines, research on high-pressure oxidation of methane/n-heptane mixtures is of interest. In this study, laminar flow reactor experiments were conducted at pressures of 21 and 100 bar, temperatures in the range 450–900 K, and under stoichiometric and fuel-lean conditions. For all conditions, the n-heptane conversion starts below 600 K. A pronounced negative temperature coefficient region was observed at 21 bar. The n-heptane was depleted at all conditions before reaching 900 K. Methane oxidation was initiated once n-heptane was consumed. Compared to the oxidation of pure n-heptane and NH3/n-heptane mixtures, the presence of methane promoted n-heptane oxidation in the full temperature range. The model from Zhang et al. provided overall a good agreement with the experimental data. However, the low-temperature conversion of n-heptane at 21 bar and stoichiometric conditions is underpredicted, possibly because some chemical coupling between n-heptane and methane is missing in the model.

Numerical simulation of hydraulic-mechanical-chemical field coupled acid fracturing in complex carbonate reservoir

In a fractured-vuggy carbonate reservoir (FVCR) are distributed many irregular natural fractures and cavities. The acid fracturing is an effective stimulation method for FVCR. It involves the hydraulic, mechanical and chemical (HMC) field coupling process. To effectively simulate the acid fracturing in FVCR, the natural fractures are hierarchically treated. For the large fractures, which play the leading role in all physical fields, the fully coupled model is adopted. While for the small fractures, which play the leading role in part physical fields, the partly coupled model is adopted. By this means, the computation stability and efficiency are significantly improved. This is particular important for the field scale simulation of FVCR. Besides this, the acidization of the natural fracture in the inactive and activated states are considered. The simulation results suggest that this method can well simulate the acid fracture activation, propagation, interaction with natural fractures and connection with cavities in FVCR. It provides a stable and efficient approach for the acid fracturing simulation in complex FVCR.

Enhancing hydrazine-assisted hydrogen production by constructing CoP-Co2P bifunctional catalysts

The development of bifunctional catalyst is very important for hydrazine-assisted hydrogen production. Herein, the CoP-Co2P@CC-300 composites self-supported on carbon cloth (CC) were prepared by chemical reduction coupling phosphating method. The required voltages of HER (-61 mV) and HzOR (-89 mV) on CoP-Co2P@CC-300 are comparable to or exceed that reported at 10 mA cm−2, which is mainly attributed to the high dispersion and intrinsic activity of CoP-Co2P nanoparticles, and good conductivity of CoP-Co2P@CC-300. Furthermore, the overall hydrazine splitting (OHzS) electrolyzer was assembled by using CoP-Co2P@CC-300 electrodes, and the required cell voltage for the OHzS is only 37 mV at 10 mA cm−2, which is lower than or comparable to that reported. The OHzS electrolyzer can still achieve efficient hydrogen production under same conditions except that power source is a dry cell or a solar panel. The DFT calculation shows that the excellent performance of CoP-Co2P@CC-300 is mainly ascribed to that CoP-Co2P can reduce the adsorption free energy of hydrogen (ΔGH*) in HER process and the energy barrier of the rate-limiting step (dehydrogenation of * N2H2 to *N2H) in HzOR process. The work provides a novel idea for hydrazine-assisted hydrogen generation by using waste dry cells or solar panels as power source.

The Stratosphere‐Ionosphere‐Protonosphere Coupling: Evidence From the Ion Composition Observations During the 2009 Sudden Stratospheric Warming

AbstractPrevious studies suggested that sudden stratospheric warmings (SSW) change the global atmosphere from troposphere to thermosphere/ionosphere. We report the low‐latitude O+ and H+ composition at 840‐km altitude during the 2009 SSW, with the DMSP satellite morning measurements. Our results indicate that the stratospheric variation around 30‐km altitude modulates the ion exchange between the ionosphere and protonosphere via the vertical and field‐aligned plasma drifts due to the enhanced lunar semidiurnal tides. The upward disturbance drift uplifts the ionospheric O+ into the protonosphere, and most O+ is changed to H+ via chemical coupling, while the O+/H+ transition height does not change under combined effects of the southward and upward disturbance drifts on 24–29 January. The disturbance drift turns downward, lowers the O+/H+ transition height, depletes the O+ density in the protonosphere, and the H+ at higher altitudes moves downward to supply the H+ at 840 km from 30 January to 5 February.

Reduction-responsive dextran-based Pt(IV) nano-prodrug showed a synergistic effect with doxorubicin for effective melanoma treatment

Melanoma, the deadliest skin cancer with high metastasis potential, has posed a great threat to human health. Accordingly, early efficient blocking of melanoma progression is vital in antitumor treatment. Herein, a reduction-responsive dextran-based Pt(IV) nano-prodrug (PDPN) was synthesized and used for doxorubicin (DOX) delivery to combat melanoma synergistically. First, PDPN was prepared by one-pot chemical coupling of carboxylated methoxy poly(ethylene glycol) (mPEG), dextran (Dex), and the crosslinking agent cisPt (IV)-COOH. PDPN had a spherical structure (Rh = 34 ± 11.3 nm). Then, DOX was encapsulated into the PDPN core to form DOX-loaded PDPN (PDPN-DOX). The obtained PDPN-DOX displayed reduction-responsive release of DOX and Pt, thus showing a synergistic anticancer effect in B16F10 cells (combination index, 0.46). Furthermore, in vivo experiments demonstrated that PDPN-DOX was effective for the synergistic treatment of subcutaneous melanoma. Collectively, the as-prepared PDPN could serve as a promising and versatile nano-prodrug carrier for the co-delivery of chemotherapeutics in tumor combination therapy.