What role does GPR65 play in the progression of osteosarcoma? Its mechanism and clinical significance.

BACKGROUND: GPR65 is a pH-sensing G-protein-coupled receptor that acts as a key innate immune checkpoint in the human tumor microenvironment, inhibiting the release of inflammatory factors and inducing significant upregulation of tissue repair genes. However, the expression pattern and function of GPR65 in osteosarcoma (OS) remain unclear. The purpose of this study was to investigate and elucidate the role of GPR65 in the microenvironment, proliferation and migration of OS. METHODS: Retrospective RNA-seq data analysis was conducted in a cohort of 97 patients with OS data in the TAEGET database. In addition, single-cell sequencing data from six surgical specimens of human OS patients was used to analyze the molecular evolution process during OS genesis. Tissues chips and bioinformatics results were used to verify GPR65 expression level in OS. MTT, colony formation, EdU assay, wound healing, transwell assay and F-actin assay were utilized to analyze cell proliferation and invasion of OS cancer cells. RNA-seq was used to explore the potential mechanism of GPR65's role in OS. RESULTS: GPR65 expression was significantly low in OS, and subgroup analysis found that younger OS patients, OS patients in metastatic status, and overall survival and progression free survival OS patients had lower GPR65 expression. From ScRNA-seq data of GSE162454, we found the expression of GPR65 is significantly positively correlated with CD4 + T cells CD8 + T cells and OS related macrophage infiltration. Verification experiment found that silencing the expression of GPR65 in osteosarcoma cells U2OS and HOS could promote the proliferation and invasion process, RNA-seq results showed that the role of GPR65 in OS cells was related to immune system, metabolism and signal transduction. CONCLUSION: The low expression of GPR65 in OS leads to high metastasis rate and poor prognosis in OS patients. The suppression of immune escape and inhibition of proliferation may be a key pathway for GPR65 to participate in the progression of OS. The current study strengthens the role of GPR65 in OS development and provides a potential biomarker for the prognosis of OS patients.

Benchmarking water adsorption on metal surfaces with ab initio molecular dynamics.

Solid-water interfaces are ubiquitous in nature and technology. In particular, technologies evolving in the green transition, such as electrocatalysis, heavily rely on the junction of an electrolyte and an electrode as a central part of the device. For the understanding of atomic-scale processes taking place at the electrolyte-electrode interface, density functional theory (DFT) has become the de facto standard. The validation of DFT's ability to simulate the interfacial solid/water interaction is crucial, and ideal simulation setups need to be identified in order to prevent avoidable systematic errors. Here, we develop a rigorous sampling protocol for benchmarking the adsorption/desorption energetics of water on metallic surfaces against experimental temperature programmed desorption, single crystal adsorption calorimetry, and thermal energy atom scattering. We screened DFT's quality on a series of transition metal surfaces, applying three of the most common exchange-correlation approximations: PBE-D3, RPBE-D3, and BEEF-vdW. We find that all three xc-functionals reflect the pseudo-zeroth order desorption of water rooted in the combination of attractive adsorbate-adsorbate interactions and their saturation at low and intermediate coverages, respectively. However, both RPBE-D3 and BEEF-vdW lead to more accurate water adsorption strengths, while PBE-D3 clearly overbinds near-surface water. We relate the variations in binding strength to specific variations in water-metal and water-water interactions, highlighting the structural consequences inherent in an uninformed choice of simulation parameters. Our study gives atomistic insight into water's complex adsorption equilibrium. Furthermore, it represents a guideline for future DFT-based simulations of solvated solid interfaces by providing an assessment of systematic errors in specific setups.

Solvation of furfural at metal-water interfaces: Implications for aqueous phase hydrogenation reactions.

Metal-water interfaces are central to understanding aqueous-phase heterogeneous catalytic processes. However, the explicit modeling of the interface is still challenging as it necessitates extensive sampling of the interfaces' degrees of freedom. Herein, we use ab initio molecular dynamics (AIMD) simulations to study the adsorption of furfural, a platform biomass chemical on several catalytically relevant metal-water interfaces (Pt, Rh, Pd, Cu, and Au) at low coverages. We find that furfural adsorption is destabilized on all the metal-water interfaces compared to the metal-gas interfaces considered in this work. This destabilization is a result of the energetic penalty associated with the displacement of water molecules near the surface upon adsorption of furfural, further evidenced by a linear correlation between solvation energy and the change in surface water coverage. To predict solvation energies without the need for computationally expensive AIMD simulations, we demonstrate OH binding energy as a good descriptor to estimate the solvation energies of furfural. Using microkinetic modeling, we further explain the origin of the activity for furfural hydrogenation on intrinsically strong-binding metals under aqueous conditions, i.e., the endothermic solvation energies for furfural adsorption prevent surface poisoning. Our work sheds light on the development of active aqueous-phase catalytic systems via rationally tuning the solvation energies of reaction intermediates.

3D Interlayer Slidable Multilayer Nano-Graphene Oxide Acrylate Crosslinked Tough Hydrogel.

The design of three-dimensional crosslinked units with a spatial structure is of great significance for improving the mechanical properties of hydrogels. However, almost all the nanocomposites incorporated in hydrogels were defined as rigid nanofillers without further discussion on the potential contribution from the spatial structure change. In this work, the 3D nano chemical crosslinker multilayer graphene oxide acrylate (mGOa) was developed as a pressure-responsive crosslinker to achieve both low elastic modulus and high compression stress by synergizing more polymer chains against the loading force through interlayer sliding. Results showed that the hydrogel crosslinked by only 2 mg/mL mGOa nano chemical crosslinker in the poly(2-hydroxyethyl methacrylate-co-acrylamide) hydrogel (molar ratio: 1:1) can effectively enhance the mechanical strength up to 14.1 ± 2.1 MPa at a high compressive strain (90.6%) with an elastic modulus of less than 0.03 MPa at the initial 5% compression, whereas the hydrogel crosslinked by methacrylated single-layer graphene oxide (sGOa) or a small-molecule chemical crosslinker, N,N'-methylene bisacrylamide, can only reach 2.3 ± 0.8 MPa and 1.4 ± 0.4 MPa, respectively. In addition, the instantaneous modulus of the mGOa crosslinked hydrogel rapidly increased to the peak value with the increase of strain. The repeated compression test of HcA-mGOa hydrogels showed the responsive increase of the modulus, which was promoted by the synergism of polymer chains under compression. This indicated that the interlayer sliding of mGOa is the key contributor to mechanical strength enhancement, which provides a new rationale to design tough hydrogels.

Modeling CoCu Nanoparticles Using Neural Network-Accelerated Monte Carlo Simulations.

The correct description of catalytic reactions happening on bimetallic particles is not feasible without proper accounting of the segregation process. In this study, we tried to shed light on the structure of large CoCu particles, for which quite controversial results were published before. However, density functional theory (DFT) is challenging to be directly used for the systematic study of nanometer-sized particles. Therefore, we constructed a neural network-based potential and further applied it to the Monte Carlo simulations for the description of the segregation phenomenon. The resulting approach shows high efficiency and can be used in systems with thousands of atoms. The accuracy and transferability of the model to other sizes and compositions make this methodology useful for solving segregation problems.

Development of a genetic algorithm and NONMEM workbench for automating and improving population pharmacokinetic/pharmacodynamic model selection.

The current approach to selection of a population PK/PD model is inherently flawed as it fails to account for interactions between structural, covariate, and statistical parameters. Further, the current approach requires significant manual and redundant model modifications that heavily lend themselves to automation. Within the discipline of numerical optimization it falls into the "local search" category. Genetic algorithms are a class of algorithms inspired by the mathematics of evolution. GAs are general, powerful, robust algorithms and can be used to find global optimal solutions for difficult problems even in the presence of non-differentiable functions, as is the case in the discrete nature of including/excluding model components in search of the best performing mixed-effects PK/PD model. A genetic algorithm implemented in an R-based NONMEM workbench for identification of near optimal models is presented. In addition to the GA capabilities, the workbench supports modeling efforts by: (1) Organizing and displaying models in tabular format, allowing the user to sort, filter, edit, create, and delete models seamlessly, (2) displaying run results, parameter estimates and precisions, (3) integrating xpose4 and PsN to facilitate generation of model diagnostic plots and run PsN scripts, (4) running regression models between post-hoc parameter estimates and covariates. This approach will further facilitate the scientist to shift efforts to focus on model evaluation, hypotheses generation, and interpretation and applications of resulting models.

Moderate Surface Segregation Promotes Selective Ethanol Production in CO2 Hydrogenation Reaction over CoCu Catalysts.

Cobalt-copper (CoCu) catalysts have industrial potential in CO/CO2 hydrogenation reactions, and CoCu alloy has been elucidated as a major active phase during reactions. However, due to elemental surface segregation and dealloying phenomena, the actual surface morphology of CoCu alloy is still unclear. Combining theory and experiment, the dual effect of surface segregation and varied CO coverage over the CoCu(111) surface on the reactivity in CO2 hydrogenation reactions is explored. The relationship between C-O bond scission and further hydrogenation of intermediate *CH2 O was discovered to be a key step to promote ethanol production. The theoretical investigation suggests that moderate Co segregation provides a suitable surface Co ensemble with lateral interactions of co-adsorbed *CO, leading to promoted selectivity to ethanol, in agreement with theory-inspired experiments.

Strong Electronic Oxide-Support Interaction over In2O3/ZrO2 for Highly Selective CO2 Hydrogenation to Methanol.

Metal oxides are widely employed in heterogeneous catalysis, but it remains challenging to determine their exact structure and understand the reaction mechanisms at the molecular level due to their structural complexity, in particular for binary oxides. This paper describes the observation of the strong electronic interaction between In2O3 and monoclinic ZrO2 (m-ZrO2) by quasi-in-situ XPS experiments combined with theoretical studies, which leads to support-dependent methanol selectivity. In2O3/m-ZrO2 exhibits methanol selectivity up to 84.6% with a CO2 conversion of 12.1%. Moreover, at a wide range of temperatures, the methanol yield of In2O3/m-ZrO2 is much higher than that of In2O3/t-ZrO2 (t-: tetragonal), which is due to the high dispersion of the In-O-In structure over m-ZrO2 as determined by in situ Raman spectra. The electron transfer from m-ZrO2 to In2O3 is confirmed by XPS and DFT calculations and improves the electron density of In2O3, which promotes H2 dissociation and hydrogenation of formate intermediates to methanol. The concept of the electronic interaction between an oxide and a support provides guidelines to develop hydrogenation catalysts.

Resistance to Long-Term Bacterial Biofilm Formation Based on Hydrolysis-Induced Zwitterion Material with Biodegradable and Self-Healing Properties.

Long-term resistance of biomaterials to the bacterial biofilm formation without antibiotic or biocide is highly demanded for biomedical applications. In this work, a novel biodegradable biomaterial with excellent capability to prevent long-term bacterial biofilm formation is prepared by the following two steps. Ethylcarboxybetaine ester analogue methacrylate (ECBEMA), poly(ethylene glycol) monomethacrylate (PEGMA), and 3-methacryloxypropyletris(trimethylsiloxy)silane (TRIS) were copolymerized to obtain p(ECBEMA-PEGMA-TRIS) (PEPT). Then, PEPT was cross-linked by isocyanate-terminated polylactic acid (IPDI-PLA-IPDI) to obtain the final PEPTx-PLAy (x and y are the number-average molecular weights (Mn) of PEPT and PLA, respectively) with optimal mechanical strength and adjustable surface regeneration rate. Static contact angle measurement, protein adsorption measurement, and attenuated total reflectance infrared (ATR-IR) results show that the PEPT19800-PLA800 film surface can generate a zwitterionic layer to resist nonspecific protein adsorption after surface hydrolysis. Quartz crystal microbalance with dissipation (QCM-D) results indicates that the PEPT19800-PLA800 film can undergo gradual degradation of the surface layer at the lowest swelling rate. Particularly, this material can efficiently resist the bacterial biofilm formation of both Gram-positive bacteria and Gram-negative bacteria over 14 and 6 days, respectively. Moreover, the material also shows an ideal self-healing feature to adapt to harsh conditions. Thus, this nonfouling material shows great potential in biomedical applications and marine antifouling coatings without antibiotic or biocide.

Enhanced CO2 Electroreduction on Neighboring Zn/Co Monomers by Electronic Effect.

It is of great significance to reveal the detailed mechanism of neighboring effects between monomers, as they could not only affect the intermediate bonding but also change the reaction pathway. This paper describes the electronic effect between neighboring Zn/Co monomers effectively promoting CO2 electroreduction to CO. Zn and Co atoms coordinated on N doped carbon (ZnCoNC) show a CO faradaic efficiency of 93.2 % at -0.5 V versus RHE during a 30-hours test. Extended X-ray absorption fine structure measurements (EXAFS) indicated no direct metal-metal bonding and X-ray absorption near-edge structure (XANES) showed the electronic effect between Zn/Co monomers. In situ attenuated total reflection-infrared spectroscopy (ATR-IR) and density functional theory (DFT) calculations further revealed that the electronic effect between Zn/Co enhanced the *COOH intermediate bonding on Zn sites and thus promoted CO production. This work could act as a promising way to reveal the mechanism of neighboring monomers and to influence catalysis.

Pharmacokinetics and pharmacodynamics of ropinirole in patients with prolactinomas.

AIMS: Treatment of prolactinomas with ergoline dopamine agonists can be complicated by intolerance and resistance. This study investigated the pharmacokinetics and pharmacodynamics of the nonergot dopamine agonist ropinirole, to assess its therapeutic potential as a novel therapy for prolactinomas. METHODS: Five female subjects with prolactinomas participated in this dose-response study. Subjects received up to three doses of ropinirole (0.5, 1.0 and 2.0 mg), each on separate occasions. Frequent blood samples for prolactin and ropinirole were collected for 24 h following drug administration. Data were analysed using noncompartmental and compartmental pharmacokinetic-pharmacodynamic (PKPD) techniques. RESULTS: Seven 24-h curves revealed increased systemic drug exposure with increasing ropinirole doses. Ropinirole concentrations peaked at 4.4 ± 2.7 h and exhibited a half-life of 5.8 ± 1.7 h. A dose-dependent prolactin nadir occurred 4.4 ± 1.2 h after drug intake and prolactin concentrations transiently normalized in two of five subjects. PKPD modelling revealed that single-dose PK of ropinirole is dose-independent and can be described with a one-compartment model with linear absorption and elimination. An indirect response model successfully captures the inhibitory effect of ropinirole on prolactin secretion and incorporates time-dependent receptor desensitization for three of five subjects whose prolactin concentrations nadired before ropinirole reached Cmax . CONCLUSIONS: This data-rich study has informed our understanding of the clinical pharmacokinetics and pharmacodynamics of ropinirole, which are successfully captured by the proposed semi-mechanistic PKPD model. This model can be used to further investigate the PKPD of ropinirole and may facilitate the identification of optimal dose regimens for the treatment of prolactinomas and the establishment of a new therapeutic option for patients impacted by this rare disease.

The Interplay between Structure and Product Selectivity of CO2 Hydrogenation.

Identification of the active structure under reaction conditions is of great importance for the rational design of heterogeneous catalysts. However, this is often hampered by their structural complexity. The interplay between the surface structure of Co3 O4 and the CO2 hydrogenation is described. Co3 O4 with morphology-dependent crystallographic surfaces presents different reducibility and formation energy of oxygen vacancies, thus resulting in distinct steady-state composition and product selectivity. Co3 O4 -0 h rhombic dodecahedra were completely reduced to Co0 and CoO, which presents circa 85 % CH4 selectivity. In contrast, Co3 O4 -2 h nanorods were partially reduced to CoO, which exhibits a circa 95 % CO selectivity. The crucial role of the Co3 O4 structure in determining the catalytic performance for higher alcohol synthesis over CuCo-based catalysts is demonstrated. As expected, Cu/Co3 O4 -2 h shows nine-fold higher ethanol yield than Cu/Co3 O4 -0 h owing to the inhibition for methanation.

Impact of Anodic Oxidation Reactions in the Performance Evaluation of High-Rate CO2 /CO Electrolysis.

The membrane-electrode assembly (MEA) approach appears to be the most promising technique to realize the high-rate CO2 /CO electrolysis, however there are major challenges related to the crossover of ions and liquid products from cathode to anode via the membrane and the concomitant anodic oxidation reactions (AORs). In this perspective, by combining experimental and theoretical analyses, several impacts of anodic oxidation of liquid products in terms of performance evaluation are investigated. First, the crossover behavior of several typical liquid products through an anion-exchange membrane is analyzed. Subsequently, two instructive examples (introducing formate or ethanol oxidation during electrolysis) reveals that the dynamic change of the anolyte (i.e., pH and composition) not only brings a slight shift of anodic potentials (i.e., change of competing reactions), but also affects the chemical stability of the anode catalyst. Anodic oxidation of liquid products can also cause either over- or under-estimation of the Faradaic efficiency, leading to an inaccurate assessment of overall performance. To comprehensively understand fundamentals of AORs, a theoretical guideline with hierarchical indicators is further developed to predict and regulate the possible AORs in an electrolyzer. The perspective concludes by giving some suggestions on rigorous performance evaluations for high-rate CO2 /CO electrolysis in an MEA-based setup.

Pediatric model-based dose optimization using a pooled exposure-response safety analysis for nivolumab and nivolumab plus ipilimumab combination in melanoma.

An exposure-response (E-R) safety analysis was conducted across adult and pediatric (<18 years) studies to evaluate the potential impact of higher nivolumab and/or ipilimumab exposures in adolescents (≥12 to <18 years) versus adults with melanoma using the approved adult dosing regimens for nivolumab alone or in combination with ipilimumab. Data from 3507 patients across 15 studies were used to examine the relationship between nivolumab-ipilimumab daily average exposure and time to grade 2+ immune-mediated adverse events (gr2+ IMAEs). Results from the E-R safety model showed ipilimumab, but not nivolumab, exposure to be a statistically significant predictor of gr2+ IMAEs. Significant covariates included sex (41% higher risk for women than men), line of therapy (19% higher for first-line than later-line), and treatment setting (26% lower for adjuvant than advanced melanoma). Younger age and lower body weight (BW) were each associated with a lower risk of gr2+ IMAEs (hazard ratio [HR]: 0.830 for 15-year-olds versus 60-year-olds and 0.84 for BW 52 kg versus 75 kg). For adolescents with melanoma treated with nivolumab in the advanced or adjuvant settings, these results are supportive of nivolumab flat dosing regimens for adolescents greater than or equal to 40 kg and BW-based dosing for adolescents less than 40 kg. These results also support adult weight-based dosing regimens for nivolumab plus ipilimumab in adolescents with advanced melanoma. This analysis suggests that although higher exposures are predicted in adolescents with lower weight compared with adults, there is no predicted immune-mediated safety risk when treated with the approved adult dosing of nivolumab with/without ipilimumab.

Microbial communities exhibit distinct diversities and assembly mechanisms in rainwater and tap-water storage systems.

Roof-harvested rainwater stored for potable and nonpotable usages represent a clean and sustainable water supply resource. However, the microbial dynamics and mechanisms of community assembly in long-termed operated rainwater storage systems remain elusive. In this study, characteristics of microbial communities in different habitats were systematically compared within rainwater and tap-water simulated storage systems (SWSSs) constructed with different tank materials (PVC, stainless steel and cement). Distinct microbial communities were observed between rainwater and tap-water SWSSs for both water and biofilm samples (ANOSIM, p < 0.05), with lower diversity indexes noted in rainwater samples. Notably, a divergent potential pathogen profile was observed between rainwater and tap-water SWSSs, with higher relative abundances of potential pathogens noted in rainwater SWSSs. Moreover, tank materials had a notable impact on microbial communities in rainwater SWSSs (ANOSIM, p < 0.05), rather than tap-water SWSSs, illustrating the distinct interplay between water chemistry and engineering factors in shaping the SWSS microbiomes. Deterministic processes contributed predominantly to the microbial community assembly in cement rainwater SWSSs and all tap-water SWSSs, which might be ascribed to the high pH levels in cement rainwater SWSSs and low-nutrient levels in all tap-water SWSSs, respectively. However, microbial communities in the PVC and stainless-steel rainwater SWSSs were mainly driven by stochastic processes. Overall, the results provided insights to the distinct microbial assembly mechanisms and potential health risks in stored roof-harvested rainwater, highlighting the importance of developing tailored microbial management strategies for the storage and utilization of rainwater.

Nivolumab and ipilimumab population pharmacokinetics in support of pediatric dose recommendations-Going beyond the body-size effect.

Body size has historically been considered the primary source of difference in the pharmacokinetics (PKs) of monoclonal antibodies (mAbs) between children aged greater than or equal to 2 years and adults. The contribution of age-associated differences (e.g., ontogeny) beyond body-size differences in the pediatric PKs of mAbs has not been comprehensively evaluated. In this study, the population PK of two mAbs (nivolumab and ipilimumab) in pediatric oncology patients were characterized. The effects of age-related covariates on nivolumab or ipilimumab PKs were assessed using data from 13 and 10 clinical studies, respectively, across multiple tumor types, including melanoma, lymphoma, central nervous system tumors (CNSTs), and other solid tumors. Clearance was lower in pediatric patients (aged 1-17 years) with solid tumors or CNST than in adults after adjusting for other covariates, including the effect of body size. In contrast, clearance was similar in pediatric patients with lymphoma to that in adults with lymphoma. The pediatric effects characterized have increased the accuracy of the predictions of the model, facilitating its use in subsequent exposure comparisons between pediatric and adult patients, as well as for exposure-response analyses to inform pediatric dosing. This study approach may be applicable to the optimization of pediatric dosing of other mAbs and possibly other biologics.

Rational Design of Three Dimensional Hollow Heterojunctions for Efficient Photocatalytic Hydrogen Evolution Applications.

The efficiency of photocatalytic hydrogen evolution is currently limited by poor light adsorption, rapid recombination of photogenerated carriers, and ineffective surface reaction rate. Although heterojunctions with innovative morphologies and structures can strengthen built-in electric fields and maximize the separation of photogenerated charges. However, how to rational design of novel multidimensional structures to simultaneously improve the above three bottleneck problems is still a research imperative. Herein, a unique Cu2O─S@graphene oxide (GO)@Zn0.67Cd0.33S Three dimensional (3D) hollow heterostructure is designed and synthesized, which greatly extends the carrier lifetime and effectively promotes the separation of photogenerated charges. The H2 production rate reached 48.5 mmol g-1 h-1 under visible light after loading Ni2+ on the heterojunction surface, which is 97 times higher than that of pure Zn0.67Cd0.33S nanospheres. Furthermore, the H2 production rate can reach 77.3 mmol g-1 h-1 without cooling, verifying the effectiveness of the photothermal effect. Meanwhile, in situ characterization and density flooding theory calculations reveal the efficient charge transfer at the p-n 3D hollow heterojunction interface. This study not only reveals the detailed mechanism of photocatalytic hydrogen evolution in depth but also rationalizes the construction of superior 3D hollow heterojunctions, thus providing a universal strategy for the materials-by-design of high-performance heterojunctions.

Self-Assembled BiGaSeAs Composite Superlattice-Structured Nanowire for Broad-Band Photodetection.

Photodetectors with a broad-band response range are widely used in many fields and are regarded as pivotal components of the modern miniaturized electronics industry. However, commercial broad-band photodetectors composed of traditional bulk semiconductor materials are still limited by complex preparation techniques, high costs, and a lack of mechanical strength and flexibility, which are difficult to satisfy the increasing demand for flexible and wearable optoelectronics. Therefore, researchers have been devoted to finding new strategies to obtain flexible, stable, and high-performance broad-band photodetectors. In this work, a novel self-assembled BiGaSeAs composite superlattice-structured nanowire was developed with a simple chemical vapor deposition method for easy fabrication. After the device assembling, the photodetector showed outstanding performance in terms of obvious Ion/Ioff (13.9), broad-band photoresponse (365-940 nm), excellent responsivity (1007.67 A/W), high detectivity (9.38 × 109 Jones), and rapid response (21 and 23 ms). The formation of microheterojunctions among various materials inside the nanowires also contributed to their extended broad-spectrum response and outstanding detection ability. These results indicate that the BiGaSeAs nanowires have potential applications in the field of flexible and wearable electronics.

Polymers in Engineering Extracellular Vesicle Mimetics: Current Status and Prospective.

The maintenance of a high delivery efficiency by traditional nanomedicines during cancer treatment is a challenging task. As a natural mediator for short-distance intercellular communication, extracellular vesicles (EVs) have garnered significant attention owing to their low immunogenicity and high targeting ability. They can load a variety of major drugs, thus offering immense potential. In order to overcome the limitations of EVs and establish them as an ideal drug delivery system, polymer-engineered extracellular vesicle mimics (EVMs) have been developed and applied in cancer therapy. In this review, we discuss the current status of polymer-based extracellular vesicle mimics in drug delivery, and analyze their structural and functional properties based on the design of an ideal drug carrier. We anticipate that this review will facilitate a deeper understanding of the extracellular vesicular mimetic drug delivery system, and stimulate the progress and advancement of this field.

Platinum nanoflowers stabilized with aloe polysaccharides for detection of organophosphorus pesticides in food.

Organophosphorus pesticides can inhibit the activity of acetylcholinesterase and cause neurological diseases. Therefore, it is crucial to establish an efficient and sensitive platform for organophosphorus pesticide detection. In this work, we extracted aloe polysaccharide (AP) from aloe vera with the number average molecular weight of 27760 Da and investigated its reducing property. We prepared aloe polysaccharide stabilized platinum nanoflowers (AP-Ptn NFs), their particle size ranges were 29.4-67.3 nm. Furthermore, AP-Ptn NFs exhibited excellent oxidase-like activity and the catalytic kinetics followed the typical Michaelis-Menten equation. They showed strong affinity for 3,3',5,5'-tetramethylbenzidine substrates. More importantly, we developed a simple and effective strategy for the sensitive colorimetric detection of organophosphorus pesticides in food using biocompatible AP-Ptn NFs. The detection range was 0.5 µg/L - 140 mg/L, which was wider than many previously reported nanozyme detection systems. This colorimetric biosensor had good selectivity and good promise for bioassay analysis.