C-reactive protein (CRP) is an important biomarker for diagnosing and therapeutic-monitoring inflammatory and cardiovascular diseases. Although the light-initiated chemiluminescent assay (LICA) enables rapid, highly sensitive homogeneous detection, its widespread applications are constrained by the stringent performance requirements for donor and acceptor microspheres. In this study, covalently integrated donor and acceptor microspheres were fabricated through a soap-free emulsion copolymerization strategy by incorporating 2-vinylthiophene, europium complexes, and a photosensitizer into a polystyrene matrix. Subsequently, oxidized dextran surface modification was introduced into the matrix to enhance biocompatibility and biomolecular conjugation efficiency. Thus obtained microspheres exhibited excellent mono-dispersity, high optical stability, and favorable surface characteristics for homogeneous immunoassays. The developed LICA-based CRP assay demonstrated satisfactory analytical performance, with a relative bias ranging from -1.0% to 0.7% for high-concentration samples and from -1.0% to 0.6% for low-concentration samples. The within-run precision showed a coefficient of variation ranging from 4.20% to 4.70%, with between-batch relative bias ranging from 4.45% to 6.46%, all of which satisfied a predefined acceptance criteria of < 8%. Compared with conventional immunoassay technology, the developed assay yielded a mean bias of -1.47 ng/mL, with 90% of measurements falling within the limits of agreement (-6.15 to 4.18 ng/mL), which demonstrates good consistency between the two assays. The developed microspheres provide a reliable material platform for homogeneous LICA and offer a promising potential for clinical applications of CRP detection.
Polyurethane elastomers (PUEs) that combine flexural resistance and antibacterial properties are urgently demanded in wearable electronics and bionic robotics. Herein, a high-performance PUE is fabricated using polytetramethylene ether glycol (PTMG) and isophorone diisocyanate (IPDI) with copper chloride (CuCl2) as a low-toxicity catalyst, followed by chain extension with dimethylglyoxime (DMG). Cu2+ not only catalyzes the polymerization but also coordinates with the oxime groups of DMG to form stable coordination crosslinks. In situ FT-IR monitoring shows that the isocyanate conversion reaches 92% within 10 min, surpassing the conventional tin catalyst dibutyltin dilaurate (DBTDL). DFT calculations revealed that Cu2+ reduces the activation energy required for the formation of urethane bonds, also confirmed by DSC measurements. The resulting elastomer exhibits excellent thermal stability (Td,5% ≥ 285 °C, as measured by TGA), high tensile strength (44.0 MPa) and toughness (218.3 MJ/m3), and flexural resistance up to 1.47 × 105 cycles. XPS and DMA analysis demonstrated that the coordination crosslinking network is responsible for the simultaneous enhancement of mechanical and thermodynamic properties. Moreover, the embedded Cu2+ imparts intrinsic antibacterial activity, achieving >99.9% inhibition against E. coli and S. aureus within 24 h. This integrated catalysis and coordination strategy offers a low-toxicity and efficient route to multifunctional polyurethane elastomers for frontier applications.
In response to the limitations of traditional transmission systems, which demand high precision and strict lubrication, and the drawbacks of single polymer-matrix gears, such as significant heat accumulation and complex wear mechanisms under high-load, high-speed conditions, this study proposes an articular cartilage-inspired metal-based multi-material composite gear with a polymeric protective layer. Combining the high thermal conductivity of metal with the self-lubricating property of short-cut carbon fiber reinforced poly(ether ether ketone) (SCF-PEEK), this composite gear enables active thermal management and intelligent self-lubrication, suppressing temperature rise, maintaining interfacial stability, and thereby enhancing the mechanical-thermal and tribological performance of the gear. As a result, it reduces meshing temperature by 28.8 % under lubrication and 18.1 % under dry friction, effectively mitigating thermal degradation of the PEEK matrix above glass transition temperature (Tg). Additionally, friction-induced structural ordering of carbon of the carbon fibers provides supplementary self-lubrication. Compared to polymer-matrix gears, the contact fatigue life of the composite bionic gear is extended by 23.4 % and 35.0 % under lubricated and dry friction conditions, respectively. Moreover, it maintains good mechanical-thermal stability even under dry friction. Synergistically complementing existing research on polymer gear reinforcement, this work presents a novel design concept for transmission applications that require high power density, long term maintenance free operation, and resilience in extreme environments such as extraterrestrial exploration, intelligent robotics, and unmanned aerial vehicles.
The study systematically investigated the effects of CHDM content and its cis/trans isomer ratio on the material's structure, thermal, optical, and mechanical properties. FT-IR and NMR analyses confirmed that CHDM was successfully incorporated into the polymer and that no isomer interconversion occurred during the polymerization process. As the CHDM content increased, the molecular weight first increased and then decreased. The weight-average molecular weight (Mw) of PH80C20C reached 78,349 g/mol. The glass transition temperature (Tg) gradually decreased, consistent with the Fox equation. For the PHCC-z series (with a CHDM content of 20 mol%), varying the cis/trans isomer ratio allowed Tg to be adjusted within the range of 158–164 °C, cis-CHDM reduced Tg by lowering chain rigidity. Mechanical testing showed that as the cis-CHDM content decreased, tensile strength increased from 48.53 MPa to 56.25 MPa, while elongation at break decreased from 61.29% to 52.46%. The modulus of toughness initially increased, reaching a peak of 25.71 MJ/m3 at PHCC-25 (25% cis), and then decreased slightly. All copolymers exhibited good thermal stability (TD,5% > 293 °C) and high transmittance (>91%). The introduction of CHDM effectively mitigates the brittleness of HBPA-PC while maintaining thermal stability and transparency, rendering PHCC promising for optical and engineering applications.
Polymer-based solid electrolytes are ideal candidates for high-energy lithium metal batteries; yet their room-temperature ionic conductivity is severely limited due to the coupled ion transport mechanism that inherently depends on polymer segmental relaxation. Herein, we propose a topological regulation strategy using polyrotaxanes (PRs) with tunable slide-ring densities to reduce the coupling of ion transport on polymer chain dynamics. By optimizing the coverage ratio (CR) of α-cyclodextrin (α-CD) rings, we show that the slide-ring topology at CR 15% is associated with a lower activation energy for Li+ migration and Arrhenius-type transport behavior, consistent with reduced coupling to polymer segmental relaxation. Specifically, the electrolyte with a 15% coverage ratio (CR 15%) exhibits a high ionic conductivity of 4.5 × 10−4 S cm−1 and a competitive lithium-ion transference number (tLi+ = 0.33) at 25 °C. Furthermore, Raman spectroscopy indicates that CR 15% exhibits the highest proportion of free ions (10.20%) among the investigated electrolytes, while XPS identifies an increased LiF fraction in the SEI, suggesting that topology-associated changes in ion association may facilitate interfacial TFSI− decomposition and contribute to LiF formation. Specifically, the electrolyte enables Li//LFP cells to maintain stable cycling for 300 cycles at 0.2 C and 60 °C, demonstrating its cell-level feasibility under thermally activated conditions. This work offers a novel topological perspective for designing high-performance polymer electrolytes with topology-regulated ion conduction.
