One step from oxides to sustainable bulk alloys.

Metallurgical production traditionally involves three steps: extracting metals from ores, mixing them into alloys by liquid processing and thermomechanical processing to achieve the desired microstructures1,2. This sequential approach, practised since the Bronze Age, reaches its limit today because of the urgent demand for a sustainable economy2-5: almost 10% of all greenhouse gas emissions are because of the use of fossil reductants and high-temperature metallurgical processing. Here we present a H2-based redox synthesis and compaction approach that reforms traditional alloy-making by merging metal extraction, alloying and thermomechanical processing into one single solid-state operation. We propose a thermodynamically informed guideline and a general kinetic conception to dissolve the classical boundaries between extractive and physical metallurgy, unlocking tremendous sustainable bulk alloy design opportunities. We exemplify this approach for the case of Fe-Ni invar bulk alloys6,7, one of the most appealing ferrous materials but the dirtiest to produce: invar shows uniquely low thermal expansion6,8,9, enabling key applications spanning from precision instruments to cryogenic components10-13. Yet, it is notoriously eco-unfriendly, with Ni causing more than 10 times higher CO2 emission than Fe per kilogram production2,14, qualifying this alloy class as a perfect demonstrator case. Our sustainable method turns oxides directly into green alloys in bulk forms, with application-worthy properties, all obtained at temperatures far below the bulk melting point, while maintaining a zero CO2 footprint.

Au-Pd separation enhances bimetallic catalysis of alcohol oxidation.

In oxidation reactions catalysed by supported metal nanoparticles with oxygen as the terminal oxidant, the rate of the oxygen reduction can be a limiting factor. This is exemplified by the oxidative dehydrogenation of alcohols, an important class of reactions with modern commercial applications1-3. Supported gold nanoparticles are highly active for the dehydrogenation of the alcohol to an aldehyde4 but are less effective for oxygen reduction5,6. By contrast, supported palladium nanoparticles offer high efficacy for oxygen reduction5,6. This imbalance can be overcome by alloying gold with palladium, which gives enhanced activity to both reactions7,8,9; however, the electrochemical potential of the alloy is a compromise between that of the two metals, meaning that although the oxygen reduction can be improved in the alloy, the dehydrogenation activity is often limited. Here we show that by separating the gold and palladium components in bimetallic carbon-supported catalysts, we can almost double the reaction rate compared with that achieved with the corresponding alloy catalyst. We demonstrate this using physical mixtures of carbon-supported monometallic gold and palladium catalysts and a bimetallic catalyst comprising separated gold and palladium regions. Furthermore, we demonstrate electrochemically that this enhancement is attributable to the coupling of separate redox processes occurring at isolated gold and palladium sites. The discovery of this catalytic effect-a cooperative redox enhancement-offers an approach to the design of multicomponent heterogeneous catalysts.

Layer-By-Layer Designed Spark-Type AuCuPt Alloy with Robust Broadband Absorption to Enhance Sensitivity in Flexible Detection of Estriol by a Lateral Flow Immunoassay.

Excessive intake of estrogen poses significant health risks to the human body; hence, there is a necessity to develop rapid detection methods to monitor its levels of addition. Gold nanoparticles (AuNPs), commonly utilized as colorimetric signal labels, find extensive application in lateral flow immunoassay (LFIA). However, the detection sensitivity of traditional AuNPs-LFIA is typically constrained by low molar extinction coefficients and reliance on a single signal. Herein, in this work, unique spark-type AuCuPt nanoflowers modified with tannic acid (AuCuPt@TA) were precisely designed by reasonable layer-by-layer element composition and green modification. The obtained AuCuPt displays robust broadband absorption spanning the visible to near-infrared spectrum, showcasing a notable molar extinction coefficient of 2.38 × 1012 M-1 cm-1 and a photothermal conversion efficiency of 48.5%. Based on this, selecting estriol (E3) as a model analyte, colorimetric/photothermal dual-signal LFIA (CLFIA and PLFIA) was developed. Limits of detection (LOD) of the CLFIA and PLFIA were achieved at 0.033 ng mL-1 and 0.021 ng mL-1, respectively, which represent a 9.3- and 14.6-fold improvement compared to the visual LOD of AuNPs-LFIA. Moreover, the application feasibility of the immunoassay was further evaluated in the milk and pork with satisfactory recoveries ranging from 86.21% to 117.91%. Thus, this work has enhanced the performance of LFIA for E3 detection and exhibited enormous potential for other sensing platform construction.

Construct a Magnetic Pt/Ru Alloy Peroxidase Mimic As a Reusable and Cost-Effective "Signal-Off" Sensing Platform for Sensitive and Wide-Linear-Range Assay.

"Signal-off" nanozyme sensing platforms are usually employed to detect analytes (e.g., ascorbic acid (AA) and alkaline phosphatase (ALP)), which are mostly based on oxidase (OXD) nanozymes. However, their drawbacks, like dissolved oxygen-dependent catalysis capability, relatively low enzyme activity, limited amount, and kind, may not favor sensing platforms' optimization. Meanwhile, with the need for sustainable development, a reusable "signal-off" sensing platform is essential for cutting down the cost of the assay, but it is rarely developed in previous studies. Magnetic peroxidase (POD) nanozymes potentially make up the deficiencies and become reusable and better "signal-off" sensing platforms. As a proof of concept, we first construct Fe3O4@polydopamine-supported Pt/Ru alloy nanoparticles (IOP@Pt/Ru) without stabilizers. IOP@Pt/Ru shows high POD activity with Vmax of 83.24 × 10-8 M·s-1 for 3,3',5,5'-Tetramethylbenzidine (TMB) oxidation. Meanwhile, its oxidation rate for TMB is slower than the reduction of oxidized TMB by reducers, favorable for a more significant detection signal. On the other hand, IOP@Pt/Ru possesses great magnet-responsive capability, making itself be recycled and reused for at least 15-round catalysis. When applying IOP@Pt/Ru for AA (ALP) detection, it performs better detectable adaptability, with a linear range of 0.01-0.2 mM (0.1-100 U/L) and a limit of detection of 0.01 mM (0.05 U/L), superior to most of OXD nanozyme-based ALP sensing platform. Finally, IOP@Pt/Ru's reusable assay was demonstrated in real blood samples for ALP assay, which has never been explored in previous studies. Overall, this study develops a reusable "signal-off" nanozyme sensing platform with superior assay capabilities than traditional OXD nanozymes, paves a new way to optimize nanozyme-based "signal-off" sensing platforms, and provides an idea for constructing inexpensive and sustainable sensing platforms.

A Pt1Pd Single-Atom Alloy Nanozyme with Boosted Enzyme-Like Activity for Efficient Photo-Mediated Tumor Therapy.

Single-atom nanozymes (SAzymes) are emerging natural enzyme mimics and have attracted much attention in the biomedical field. SAzymes with Metal─Nx sites designed on carbon matrixes are currently the mainstream in research. It is of great significance to further expand the types of SAzymes to enrich the nanozyme library. Single-atom alloys (SAAs) are a material in which single-atom metal sites are dispersed onto another active metal matrix, and currently, there is limited research on their enzyme-like catalytic performance. In this work, a biodegradable Pt1Pd SAA is fabricated via a simple galvanic replacement strategy, and for the first time reveals its intrinsic enzyme-like catalytic performance including catalase-, oxidase-, and peroxidase-like activities, as well as its photodynamic effect. Experimental characterizations demonstrate that the introduction of single-atom Pt sites contributes to enhancing the affinity of Pt1Pd single-atom alloy nanozyme (SAAzyme) toward substrates, thus exhibiting boosted catalytic efficiency. In vitro and in vivo experiments demonstrate that Pt1Pd SAAzyme exhibits a photo-controlled therapeutic effect, with a tumor inhibition rate of up to 100%. This work provides vital guidance for opening the research direction of SAAs in enzyme-like catalysis.

A Highly Sensitive and Selective Fluorescent Sensor for Folic Acid Detection Based on D-penicillamine Stabilized Ag/Cu Alloy Nanoclusters.

In this work, a highly sensitive and selective method for detecting folic acid (FA) was developed using D-penicillamine (DPA) stabilized Ag/Cu alloy nanoclusters (DPA@Ag/Cu NCs). The yellow emission of DPA@Ag/Cu NCs was found to be quenched upon the addition of FA to the system. The fluorescence intensity quenching value demonstrated a linear relationship with FA concentrations ranging from 0.01 to 1200 µM, with a limit of detection (LOD) of 5.3 nM. Furthermore, the detection mechanism was investigated through various characterization analyses, including high resolution transmission electron microscopy, fluorescence spectra, ultraviolet-visible absorption spectra, and fluorescence lifetime. The results indicated that the fluorescence quenching induced by FA was a result of electron transfer from FA to the ligands of DPA@Ag/Cu NCs. The selectivity of the FA sensor was also evaluated, showing that common amino acids and inorganic ions had minimal impact on the detection of FA. Moreover, the standard addition method was successfully applied to detect FA in human serum, chewable tablets and FA tablets with promising results. The use of DPA@Ag/Cu NCs demonstrates significant potential for detecting FA in complex biological samples.

Cutibacterium acnes biofilm formation is influenced by bone microenvironment, implant surfaces and bacterial internalization.

BACKGROUND: The bacterial persistence, responsible for therapeutic failures, can arise from the biofilm formation, which possesses a high tolerance to antibiotics. This threat often occurs when a bone and joint infection is diagnosed after a prosthesis implantation. Understanding the biofilm mechanism is pivotal to enhance prosthesis joint infection (PJI) treatment and prevention. However, little is known on the characteristics of Cutibacterium acnes biofilm formation, whereas this species is frequently involved in prosthesis infections. METHODS: In this study, we compared the biofilm formation of C. acnes PJI-related strains and non-PJI-related strains on plastic support and textured titanium alloy by (i) counting adherent and viable bacteria, (ii) confocal scanning electronic microscopy observations after biofilm matrix labeling and (iii) RT-qPCR experiments. RESULTS: We highlighted material- and strain-dependent modifications of C. acnes biofilm. Non-PJI-related strains formed aggregates on both types of support but with different matrix compositions. While the proportion of polysaccharides signal was higher on plastic, the proportions of polysaccharides and proteins signals were more similar on titanium. The changes in biofilm composition for PJI-related strains was less noticeable. For all tested strains, biofilm formation-related genes were more expressed in biofilm formed on plastic that one formed on titanium. Moreover, the impact of C. acnes internalization in osteoblasts prior to biofilm development was also investigated. After internalization, one of the non-PJI-related strains biofilm characteristics were affected: (i) a lower quantity of adhered bacteria (80.3-fold decrease), (ii) an increase of polysaccharides signal in biofilm and (iii) an activation of biofilm gene expressions on textured titanium disk. CONCLUSION: Taken together, these results evidenced the versatility of C. acnes biofilm, depending on the support used, the bone environment and the strain.

3D printed microfluidic valve on PCB for flow control applications using liquid metal.

Direct 3D printing of active microfluidic elements on PCB substrates enables high-speed fabrication of stand-alone microdevices for a variety of health and energy applications. Microvalves are key components of microfluidic devices and liquid metal (LM) microvalves exhibit promising flow control in microsystems integrated with PCBs. In this paper, we demonstrate LM microvalves directly 3D printed on PCB using advanced digital light processing (DLP). Electrodes on PCB are coated by carbon ink to prevent alloying between gallium-based LM plug and copper electrodes. We used DLP 3D printers with in-house developed acrylic-based resins, Isobornyl Acrylate, and Diurethane Dimethacrylate (DUDMA) and functionalized PCB surface with acrylic-based resin for strong bonding. Valving seats are printed in a 3D caterpillar geometry with chamber diameter of 700 µm. We successfully printed channels and nozzles down to 90 µm. Aiming for microvalves for low-power applications, we applied square-wave voltage of 2 Vpp at a range of frequencies between 5 to 35 Hz. The results show precise control of the bistable valving mechanism based on electrochemical actuation of LMs.

Percutaneous intervention of a giant native coronary artery aneurysm using self-expanding stents.

In the absence of standardized management guidelines, coronary artery aneurysms (CAAs) present therapeutic challenges. Percutaneous coronary intervention (PCI) is rarely explored, especially in giant aneurysms with persistent angina, where surgery might be presumed as a preferred option. We describe the technical aspects and feasibility of PCI using Gore Viabahn expanded polytetrafluoroethylene (ePTFE)-covered nitinol self-expanding stents in a 66-year-old woman with a complex medical history and an enlarging, symptomatic right coronary artery aneurysm. The case was complicated by endoleak after the first stent, but intravascular ultrasound guidance enabled the precise deployment of additional stents, resulting in the successful exclusion of the aneurysm. This case demonstrates steps to successful CAA PCI with Gore Viabahn ePTFE-covered nitinol self-expanding stents and emphasizes that in unsuitable surgical candidates, PCI might be a potential alternative for symptomatic CAAs.

Bimetallic Gold/Silver and Bioactive Camptothecin Hybrid Nanoparticles for Eradication of Cancer Stem Cells in a Combination Manner.

The defeat of cancer is still a challenge due to the existence of cancer stem cells (CSCs) because they resist conventional chemotherapy via multifactor regulated mechanisms. Consequently, one-dimensional action toward CSCs cannot work. Herein, we used rationally designed hybrid nanoparticles as a combined cancer therapy, hoping to form a multidimensional control network. In this paper, gold/silver alloy nanoparticle decorated camptothecin nanocrystals were formulated according to complementary anti-CSC mechanisms from gold, silver, and organic drug. This smart drug formulation could combine chemotherapy and thermotherapy, target different tumor sites, and demonstrate versatile toxicity profiles from each component. Major results indicated that this nanosystem demonstrated indiscriminately effective cytotoxic/proapoptotic/necrotic activity against bulk MCF-7 cells and their CSC subpopulation, in particular under laser ablation. Moreover, this nanosystem displayed enhanced antineoplastic activity against CSC spheroids, resulting in a significant reduction in their number and size, that is, their self-renewal capacity. All the results indicated that CSCs upon treatment of these new hybrid nanoparticles underwent reduced stemness and conversion from the original quiescent state and recovered their sensitivity toward chemotherapy. The relevant anticancer mechanism was ascribed to NIR-pH dual responsive drug release, synergistic/combined thermo-chemotherapy of organic drug and inorganic alloy nanoparticles, enhanced cellular uptake mediated by alloy nanoparticles, and Ag+-induced biomembrane damage. This thermo-chemotherapy platform provides a new combinatorial strategy for inorganic and organic agents in the complete elimination of CSCs.

Degradation Behavior of Medical MgZZC-1 in Various Simulated Body Fluids.

Magnesium-based biodegradable metal bone implants exhibit superior mechanical properties compared to biodegradable polymers for orthopedic and cardiovascular stents. In this study, MgZZC-x (x = 1, 1.2) alloys were screened by in vitro biocompatibility tests in three simulated body fluids under nontoxic conditions. The MgZZC-1 alloys with better biocompatibility were selected to predict the days required for complete degradation. The evolution of degradation products was analyzed, and the mechanism of formation of the product film was inferred. A degradation kinetic model was established to investigate the effect of MEM components on the degradation of the alloys. The results demonstrate that the proteins in MEM can greatly retard the degradation progress by attaching to the surface of MgZZC-1 alloys, which are predicted to degrade completely within 341 days. The carbonate and phosphate buffers were adjusted to pH in MEM solution, delaying the degradation of magnesium alloys. This process in MEM more accurately reflects the actual degradation in the body and is superior to that in Hanks and SBF solutions. This study will promote the application of biodegradable materials in clinical medicine.

Investigation of the Relationship between Surface Features, Protein Adsorption, and Osteoimmunomodulation: The Case of a Chemically Treated Titanium Alloy.

This paper deals with the combined effects of immune response and osseointegration because of the lack of comprehensive studies on this topic. An antibacterial Ti surface was considered because of the high risk of infection for titanium bone implants. A chemically treated Ti6Al4 V alloy [Ti64(Sr-Ag)] with a microporous and Sr-Ag doped surface was compared to a polished version (Ti64) regarding protein adsorption (albumin and fibronectin) and osteoimmunomodulation. Characterization via fluorescence microscopy and zeta potential showed a continuous fibronectin layer on Ti64(Sr-Ag), even with preadsorbed albumin, while it remained filamentous on Ti64. Macrophages (differentiated from THP-1 monocytes) were cultured on both surfaces, with viability and cytokine release analyzed. Differently from Ti64, Ti64(Sr-Ag) promoted early anti-inflammatory responses and significant downregulation of VEGF. Ti64(Sr-Ag) also enhanced human bone marrow mesenchymal cell differentiation toward osteoblasts, when a macrophage-conditioned medium was used, influencing ALP production. Surface properties in relation to protein adsorption and osteoimmunomodulation were discussed.

Enhancing Bactericidal Properties of Ti6Al4V Surfaces through Micro and Nano Hierarchical Laser Texturing.

Orthopedic and dental implants made from Ti6Al4V are widely used due to their excellent mechanical properties and biocompatibility. However, the long-term performance of these implants can be compromised by bacterial infections. This study explores the development of hierarchically textured surfaces with enhanced bactericidal properties to address such challenges. Hierarchical surface structures were developed by combining microscale features produced by a microsecond laser and superimposed submicron features produced using a femtosecond laser. Microscale patterns were produced by the pulsed laser surface melting process, whereas submicrometer laser-induced periodic surface structures were created on top of them by femtosecond laser processing. Escherichia coli bacterial cells were cultured on the textured surface. After 24 h, a staining analysis was performed using SYTO9 and PI dyes to investigate the samples with a confocal microscope for live dead assays. Results showed bacterial colony formation onto the microscale surface textures with live bacterial cells, whereas the hierarchical surface textures display segregated and physically damaged bacterial cell attachments on surfaces. The hierarchical surface textures showed ∼98% dead bacterial cells due to the combined effect of its multiscale surface features and oxide formation during the laser processing steps. The efficacy of hierarchical surface textures in enhancing the antibacterial behavior of Ti6Al4V implants is evident from the conducted research. Such laser-based surface treatments can find potential applications in different industrial sectors.

Alloyed Trimetallic Nanocomposite as an Efficient and Recyclable Solid Matrix for Ideonella sakaiensis Lipase Immobilization.

In this work, a trimetallic (Ni/Co/Zn) organic framework (tMOF), synthesized by a solvothermal method, was calcinated at 400 and 600 °C and the final products were used as a support for lipase immobilization. The material annealed at 400 °C (Ni-Co-Zn@400) had an improved surface area (66.01 m2/g) and pore volume (0.194 cm3/g), which showed the highest enzyme loading capacity (301 mg/g) with a specific activity of 0.196 U/mg, and could protect the enzyme against thermal denaturation at 65 °C. The optimal pH and temperature for the lipase were 8.0 and 45 °C but could tolerate pH levels 7.0-8.0 and temperatures 40-60 °C. Moreover, the immobilized enzyme (Ni-Co-Zn@Lipase, Ni-Co-Zn@400@Lipase, or Ni-Co-Zn@600@Lipase) could be recovered and reused for over seven cycles maintaining 80, 90, and 11% of its original activity and maintained a residual activity >90% after 40 storage days. The remarkable thermostability and storage stability of the immobilized lipase suggest that the rigid structure of the support acted as a protective shield against denaturation, while the improved pH tolerance toward the alkaline range indicates a shift in the ionization state attributed to unequal partitioning of hydroxyl and hydrogen ions within the microenvironment of the active site, suggesting that acidic residues may have been involved in forming an enzyme-support bond. The high enzyme loading capacity, specific activity, encouraging stability, and high recoverability of the tMOF@Lipase indicate that a multimetallic MOF could be a better platform for efficient enzyme immobilization.

Prospective evaluation of ultrasound features of magnesium-based bioabsorbable screw resorption in pediatric fractures.

OBJECTIVE: Bioabsorbable magnesium-based alloy screws release gas upon resorption. The resulting findings in the adjacent soft tissues and joints may mimic infection. The aim of the study was to evaluate the ultrasound (US) findings in soft tissues and joints during screw resorption. METHODS: Prospectively acquired US studies from pediatric patients treated with magnesium screws were evaluated for screw head visibility, posterior acoustic shadowing, twinkling artifact, foreign body granuloma, gas (soft tissue, intra-articular), alterations of the skin and subcutaneous fat, perifascial fluid, localized fluid collections, hypervascularization, and joint effusion. RESULTS: Sixty-six US studies of 28 pediatric patients (nfemale = 9, nmale = 19) were included. The mean age of the patients at the time of surgery was 10.84 years; the mean time between surgery and ultrasound was 128.3 days (range = 6-468 days). The screw head and posterior acoustic shadowing were visible in 100% of the studies, twinkling artifact in 6.1%, foreign body granuloma in 92.4%, gas locules in soft tissue in 100% and intra-articular in 18.2%, hyperechogenicity of the subcutaneous fat in 90.9%, cobblestoning of the subcutaneous fat in 24.2%, loss of normal differentiation between the epidermis/dermis and the subcutaneous fat in 57.6%, localized fluid collection in 9.9%, perifascial fluid in 12.1%, hypervascularization in 27.3%, and joint effusion in 18.2%. CONCLUSION: US findings in pediatric patients treated with magnesium screws strongly resemble infection, but are normal findings in the setting of screw resorption. CLINICAL RELEVANCE STATEMENT: Bioabsorbable magnesium-based alloy screws release gas during resorption. The resulting US findings in the adjacent soft tissues and joints in pediatric patients may mimic infection, but are normal findings. KEY POINTS: • Bioabsorbable magnesium-based alloy screws release gas upon resorption. • The resulting ultrasound findings in children's soft tissues and joints closely resemble those of soft tissue infection or osteosynthesis-associated infection. • Be familiar with these ultrasound findings in order to avoid inadvertently misdiagnosing a soft tissue infection or osteosynthesis-associated infection.

Early Outcomes of Interwoven Nitinol Wire Stent Placement versus Endarterectomy for the Treatment of Atherosclerotic Disease of the Common Femoral Artery.

PURPOSE: To compare the clinical outcomes of common femoral artery (CFA) atherosclerotic disease treated with either surgical endarterectomy or an interwoven nitinol wire stent system. MATERIALS AND METHODS: A retrospective review was conducted of all patients with chronic, de novo atherosclerotic CFA disease treated with surgical endarterectomy (CFAE) or stent placement between July 2019 and March 2022. Outcome measures assessed up to 12 months after procedure included clinical improvement, primary restenosis, target vessel revascularization (TVR), major adverse limb events (MALEs), and all-cause mortality. RESULTS: Thirty-nine stents were deployed in 33 patients, and 56 CFAEs were performed in 55 patients. No differences were noted in the rate of primary patency (95.5% vs 94.4%, P = .618), TVR (2.9% vs 1.8%, P = .777), MALE (5.1% vs 5.4%, P = .949), and all-cause mortality (14.1% vs 3.6%, P = .076) between the stent and CFAE groups up to 12 months after procedure. There was greater improvement in median clinical severity in the stent group than in the CFAE group (Rutherford score change of 3.0 vs 1.5, P = .013). The median length of stay was less for the stent group (3 vs 7 days, P = .002), and there was a lower likelihood of severe or disabling adverse events in the stent group (0 vs 9 cases, P = .010). CONCLUSIONS: Patients treated with an interwoven nitinol wire stent had patency rates comparable to those treated with CFAE while having a lower incidence of severe adverse events and a shorter length of hospital stay than those who underwent CFAE.

Fatigue Test Method to Evaluate the 50 Year Durability of Venous Stents.

OBJECTIVE: Iliofemoral venous obstructive disease can result in significant, potentially debilitating symptoms that can negatively affect quality of life. Unlike arterial disease, patients with deep venous disease have a significantly lower median age, therefore the need for long term stent patency becomes a matter of decades rather than years. Furthermore, iliofemoral lesions frequently require stent placement across the inguinal ligament. Such stents are subject to dynamic stress from leg movement and associated concerns for device fatigue, resulting in stent fracture. The aim of this study was to describe an in vitro 50 year stent fatigue test method designed to assess durability against dynamic stress induced device fracture. METHODS: Through literature review, cadaver studies, and computer modelling, the most challenging loading was confirmed to be hip flexion across the inguinal ligament. This occurs when the patient adjusts between a seated and standing position. Sit to stand hip flexion at the inguinal ligament was effectively simulated on the bench in this in vitro experimental study. RESULTS: When tested under challenge parameters, hip flexion was reliably found to cause fractures in non-venous nitinol stents. However, a dedicated self expanding nitinol venous stent, engineered for improved durability, underwent up to 50 years of simulated loading on the bench with 15% (3/20) of stents experiencing fractures at 50 years, compared with fractures in 35% (14/40) of non-venous stents tested to 1.4 years; no statistical testing was performed as durations do not match and the objective was to demonstrate the test method. CONCLUSION: The presented fatigue test method is a suitable approach for evaluating the durability of stents intended for venous use. Venous stents demonstrated superior fatigue resistance compared with non-venous stents via in vitro hip flexion testing.

The BioMimics 3D Helical Centreline Nitinol Stent in Chronic Limb Threatening Ischaemia and Complex Lesions: Three Year Outcomes of the MIMICS-3D Registry.

OBJECTIVE: There is a need for improved outcomes in the endovascular treatment of patients suffering from chronic limb threatening ischaemia (CLTI), highly calcified lesions, and chronic total occlusions (CTOs). The helical centreline self expanding BioMimics 3D stent might be particularly useful in these high risk subsets, combining flexibility and fracture resistance with radial strength. Herein, the performance of the BioMimics 3D stent was assessed in these high risk subsets. METHODS: MIMICS-3D is a prospective, multicentre, European real world registry. This was a post hoc analysis, comparing patients with CLTI vs. intermittent claudication (IC), lesions with bilateral calcification vs. those without (peripheral arterial calcium scoring system [PACSS] 3,4 vs. PACSS 0 - 2), and CTO vs. no CTO. Propensity score matching was performed to reduce the impact of baseline variables. The 36 month endpoints were clinically driven target lesion revascularisation (CD-TLR), death, major target limb amputation, and stent patency. RESULTS: A total of 507 patients were enrolled. At 36 months, patients with CLTI had lower freedom from major amputation than patients with IC (92.6% vs. 100%, p < .001). In terms of primary patency, patients with CTO had lower patency rates than those without (63.9% vs. 77.8%, p = .003), but the difference reduced after propensity score matching (70.5% vs. 76.8%, p = .43). Primary patency was not impaired for patients with PACSS 3,4 or patients with CLTI. Freedom from CD-TLR was not significantly different among the groups and was 73.8% for CLTI vs. 78.9% for IC (p = .15), 77.6% for PACSS 3,4 vs. 78.7% for PACSS 0 - 2 (p = .55), and 75.6% for CTO vs. 81.0% for no CTO (p = .11). CONCLUSIONS: The outcome of the MIMICS-3D registry suggests that the BioMimics 3D stent is effective in the endovascular treatment of complex femoropopliteal lesions and in CLTI. Future randomised controlled trials should confirm its non-inferiority or superiority compared with existing alternatives.

Highly Sensitive, Stable InP Quantum Dot Fluorescent Probes for Quantitative Immunoassay Through Nanostructure Tailoring and Biotin-Streptavidin Coupling.

Nontoxic, highly sensitive InP quantum dot (QD) fluorescent immunoassay probes are promising biomedical detection modalities due to their unique properties. However, InP-based QDs are prone to surface oxidation, and the stability of InP QD-based probes in biocompatible environments remains a crucial challenge. Although the thick shell can provide some protection during the phase transfer process of hydrophobic QDs, the photoluminescence quantum yield (PLQY) is generally decreased because of the contradiction between lattice stress relaxation and thick shell growth. Herein, we developed thick-shell InP-based core/shell QDs by inserting a ZnSeS alloy layer. The ternary ZnSeS intermediate shell could effectively facilitate lattice stress relaxation and passivate the defect states. The synthesized InP/ZnSe/ZnSeS/ZnS core/alloy shell/shell QDs (CAS-InP QDs) with nanostructure tailoring revealed a larger size, high PLQY (90%), and high optical stability. After amphiphilic polymer encapsulation, the aqueous CAS-InP QDs presented almost constant fluorescence attenuation and stable PL intensity under different temperatures, UV radiation, and pH solutions. The CAS-InP QDs were excellent labels of the fluorescence-linked immunosorbent assay (FLISA) for detecting C-reactive protein (CRP). The biotin-streptavidin (Bio-SA) system was first introduced in the FLISA to further improve the sensitivity, and the CAS-InP QDs-based SA-Bio sandwich FLISA realized the detection of CRP with an impressive limit of detection (LOD) of 0.83 ng/mL. It is believed that the stable and sensitive InP QD fluorescent probes will drive the rapid development of future eco-friendly, cost-effective, and sensitive in vitro diagnostic kits.

Dilute Alloys Based on Au, Ag, or Cu for Efficient Catalysis: From Synthesis to Active Sites.

The development of new catalyst materials for energy-efficient chemical synthesis is critical as over 80% of industrial processes rely on catalysts, with many of the most energy-intensive processes specifically using heterogeneous catalysis. Catalytic performance is a complex interplay of phenomena involving temperature, pressure, gas composition, surface composition, and structure over multiple length and time scales. In response to this complexity, the integrated approach to heterogeneous dilute alloy catalysis reviewed here brings together materials synthesis, mechanistic surface chemistry, reaction kinetics, in situ and operando characterization, and theoretical calculations in a coordinated effort to develop design principles to predict and improve catalytic selectivity. Dilute alloy catalysts─in which isolated atoms or small ensembles of the minority metal on the host metal lead to enhanced reactivity while retaining selectivity─are particularly promising as selective catalysts. Several dilute alloy materials using Au, Ag, and Cu as the majority host element, including more recently introduced support-free nanoporous metals and oxide-supported nanoparticle "raspberry colloid templated (RCT)" materials, are reviewed for selective oxidation and hydrogenation reactions. Progress in understanding how such dilute alloy catalysts can be used to enhance selectivity of key synthetic reactions is reviewed, including quantitative scaling from model studies to catalytic conditions. The dynamic evolution of catalyst structure and composition studied in surface science and catalytic conditions and their relationship to catalytic function are also discussed, followed by advanced characterization and theoretical modeling that have been developed to determine the distribution of minority metal atoms at or near the surface. The integrated approach demonstrates the success of bridging the divide between fundamental knowledge and design of catalytic processes in complex catalytic systems, which can accelerate the development of new and efficient catalytic processes.