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Abstract For the determination of dopamine (DA) in serum samples, a quenching-type electrochemiluminescence sensor (MIECLS) was constructed in this study. Upconversion nanoparticles (UCNPs) enhanced by covalent organic frameworks (COFs)-based hybrid and oligoaniline-crosslinked gold nanoparticles (AuNPs) imprinting recognition sites were introduced in electrochemiluminescence (ECL) system at the first time. The porous COFs-based hybrid with large specific surface area was modified on the electrode firstly to hold more UCNPs and imprinting recognition sites. AuNPs was employed in the developed sensor for two objectives: 1) AuNPs on the COFs-based hybrid enabled the hybrid to tunnel the electrons, which helped to improve the ECL intensity; 2) AuNPs-based thioaniline units (PATP@AuNPs) electropolymerized on the electrode in the presence of template to form oligoaniline-crosslinked AuNPs matrix. Then the exclusion of template from matrix yielded the molecularly three-dimensional imprinted contours with conductivity, which facilitated specific recognition and further amplified the ECL. The double recognition mode in this work involves the recognition effect of imprinted contours and quenching effect of o -benzoquinone species. The quantum chemical calculation was performed to analyze the possible recognition and the binding mechanisms of molecularly three-dimensional imprinted contours. The results showed imprinted contours could bind the targets by complementary spatial cavities and weak interactions. The proposed approach yielded a wide detection range (10–14–10−6 M), low limit of detection (LOD = 2 ×10–15 M) and acceptable recoveries (93.25–112.97%) in rat serum sample, demonstrating that the developed method holds great promise to be applied to DA detection in practical samples. Highlights • CTpBD-Au enhanced UCNPs and oligoaniline-crosslinked AuNPs imprinting recognition sites were introduced in ECL system. • The double recognition was constructed by the recognition effect of imprinted contours and quenching effect for ECL. • The proposed approach yields a wide detection range, low limit of detection and acceptable recoveries in rat serum sample. [ABSTRACT FROM AUTHOR]

A novel molecular imprinting fluorescent sensor synthesized avoiding complicated design and synthesis of a fluorescent functional monomer, and without the extra cost of additional fluorescence materials (quantum dots, carbon dots and fluorescein), only by a click reaction making the common protein imprinting polymers upgraded to a fluorescent sensing material which can be applied to the fast detection of glycoproteins. In this study, a common protein imprinted polymer (protein-IP) which containing a disulfide bond in the imprinted cavities was first synthesized, then the disulfide linkage was cleaved by reduction, the exposed thiol groups were used for the click reaction to introduce 4-vinyl phenylboronic acid to improve the imprinted recognition for glycoproteins and convert recognition behavior into fluorescent signal simultaneously in one-step site-specific post-imprinting modifications (PIMs). Good linear relationship was obtained in the range of 0.1–10 mg mL −1 by fluorescence assay, comparison of the adsorption capacity of the MIPs before and after modification proved that the method has no negative impact on the imprinting effect and exhibit good imprinting effect for glycoproteins of different molecular size and weight. [ABSTRACT FROM AUTHOR]

Effective wound management has the potential to reduce both the duration and cost of wound healing. However, traditional methods often rely on direct observation or complex and expensive biological testing to monitor and evaluate the invasive damage caused by wound healing, which can be time-consuming. Biosensors offer the advantage of precise and real-time monitoring, but existing devices are not suitable for integration with sensitive wound tissue due to their external dimensions. Here, we have designed a self-powered biosensing suture (SPBS) based on biofuel cells to accurately monitor glucose concentration at the wound site and promote wound healing. The anode of the SPBS consists of carbon nanotubes-modified carbon fibers, tetrathiafulvalene (TTF), and glucose oxidase (GOx), while the cathode is composed of Ag 2 O and carbon nanotubes modified nanotubes modified carbon fibers. It was observed that SPBS exhibited excellent physical and chemical stability in vitro. Regardless of different bending degrees or pH values, the maximum power density of SPBS remained above 92%, which is conducive to long-term dynamic evaluation. Furthermore, the voltage generated by SPBS reflects blood glucose concentration, and measurements at wound sites are consistent with those obtained using a commercially available blood glucose meter. SPBS achieves the healing effect of traditional medical sutures after complete healing within 14 days. It offers valuable insights for intelligent devices dedicated to real-time wound monitoring. [ABSTRACT FROM AUTHOR]

For the first time, a quantitative photothermal-sensing immunochromatographic sensor (PT-ICS) is described using Au nanoparticle-enhanced two-dimensional black phosphorus (BP-Au) as signal component for the photothermal-sensing antibody probe. BP-Au has good photothermal properties at 808 nm, and the photothermal conversion efficiency of the BP-Au nanosheet increased by 12.9% over the black phosphorus nanosheet alone. In addition, the antibody was more easily coupled to this nanosheet due to the good physical adsorption capacity of Au nanoparticles. We used this PT-ICS to detect veterinary antibiotics enrofloxacin (ENR), the photothermal-sensing antibody probe was competitive captured by ENR target and antigen coating on test (T) lines of the sensor. This process was exothermic under an 808 nm laser, and the thermal energy decreased as the ENR in the sample increased. This thermal energy was recorded by an infrared thermal imager or an infrared thermometer, and the concentration of the ENR residues in animal-derived foods was obtained by analyzing the temperature changes in T-lines. Under optimal conditions, the PT-ICS exhibited sensitive and specific detection of ENR from 0.03 μg/L to 10 μg/L with detection limits of 0.023 μg/L. The results agreed well with a commercial enzyme-linked-immunosorbent assay kit. This PT-ICS provided a promising strategy for the detection of ENR residues in animal-derived foods and expected to be used for the detection of other highly sensitive biomacromolecules. fx1 • Au nanoparticle-enhanced black phosphorus nanosheet was synthesized and used as photothermal-sensing immuno-probe. • Developed a novel photothermal sensing immunochromatographic sensor for ENR detecting in animal derived food samples. • Quantitative analysis was realized by an infrared thermometer or a thermal imager. • The photothermal-sensing immunochromatographic sensor increases the sensitivity and improves the detection range of an assay. [ABSTRACT FROM AUTHOR]

A novel 3D C-based nano Cu 2 [Fe(CN) 6 ]-C (C–CuFC) nanocrystals with unusually electrical-conductivity was synthesized based on reduced carboxylated graphene oxide (COOH-rGO) and copper nanoparticles (CuNPs) by using room temperature (RT) K 3 [Fe(CN) 6 ]-solution growth. During the fabrication of C–CuFC electrode, rGO-COOH enabled the Cu2+ to tunnel the electrons, which contributed to form a 3D petal-liked structure (Flo.-C), meanwhile, the synthetic 3D Flo.-C induced crystal of the electroactive cubic CuFC–C in K 3 [Fe(CN) 6 ] solution. Another, the [Cu(CN) 4 ]2-, [Fe(CN) 6 ]4- and quinones with high conductivity were produced, and the free Fe2+ and Cu2+ existed on solid (electrode)−liquid (electrolyte) interface also increased the electric signal directly, so this CuFC–C showed amazing electrochemical current, which was 29-folds larger than the current intensity of bare electrode. With attaching on electrode, CuFC–C nanomaterial can significantly improve the electrical conductivity of sensor. Impressively, such 3D-CuFC-C nanocrystals shows excellent anchoring ability toward the AFP-antibodies (Ab) ascribed to the unreduced COOH-group of CuFC–C. Hence, a 3D Ab/CuFC–C/GCE electrochemical immunosensor was constructed based the promising conductivity and biocompatibility. Meanwhile, the Ab/CuFC–C/GCE biosensor exhibited ultra-low detection limit (LOD: 1.40 × 10−8 ng mL−1) and a fast response time (0.4 min). Additionally, the developed biosensor displayed excellent stability and good recovery (92.07%–101.91%) for AFP in human serum. Therefore, this sensing-platform has great potential in rapidly and sensitively detecting biomarkers and the other race targets. [Display omitted] [ABSTRACT FROM AUTHOR]

A novel approach to synthesize molecularly imprinted polymer (MIP) nanoparticles using a MIL-101 support (a type of metal–organic framework) is reported herein for the first time; the sample is referred as MIL@MIP. The nanoparticles were well distributed within the polymer film, and exhibit an octahedral shape, satisfied thermal stability, and a high specific surface area (SSA) of 1579.43 m 2 g −1 . The adsorption behavior of MIL@MIP toward metolcarb in aqueous solution was subsequently examined. The synthesized MIL@MIP displayed satisfactory high transfer mass rates and a high selective adsorption affinity for metolcarb. Based on these results, a quartz crystal microbalance (QCM) sensor based on MIL@MIP was subsequently constructed and examined for the sensitive detection of metolcarb. Under optimal conditions, the detection limit of the system assessed in pear juice was 0.0689 mg L −1 within a linear concentration range of 0.1–0.9 mg L −1 . MIL@MIP–QCM system combines the advantages of MIL-101 and molecularly imprinted technology (MIT), thereby achieving high detection sensitivity and selectivity. The current findings suggest the potential of MIL@MIP for detecting trace level pesticides and veterinary drugs for food safety and environmental control. [ABSTRACT FROM AUTHOR]

A bimodal 3D-electrochemiluminescence (ECL) analysis method was developed, which integrated simpleness, label-free, high-throughput and real time detection together. Firstly, a novel 3D copper-based nanosheet micro-material (Cu-Flo. NMs) coupled with gold nanoparticles/Cysteine (Cu-Flo.@AuNPs-Cys) was prepared to use as the versatile label for both colorimetric and ECL techniques. The 3D-Cu-Flo.@AuNPs-Cys having glucose oxidase-like activity could catalyze glucose to produce H 2 O 2 in situ, which was further found to be capable of exhibiting a 30.95-fold higher ECL-intensity for luminol than bare glassy carbon electrodes (GCE). Taking advantages of the 3D-Cu-Flo.@AuNPs-Cys above, a colorimetric and ECL-channel sensor (GCE/3D-Cu-Flo.@AuNPs-Cys) were constructed simultaneously for glucose detection. The fabricated sensor displayed a wide linear range (Glucose: 0.001–50 mmol L−1, AFP: 2.25 × 10−7–225 ng mL−1), impressive low limit of detection (Glucose: 1.27 × 10−7 mol L−1, AFP: 1.92 × 10−8 ng mL−1, S/N = 3) and acceptable recovery (Glucose: 94% ∼ 104%, AFP: 96.04% ∼ 102.29%) in practical sample. Furthermore, the biosensor showed ultrafast (0.5 min) analysis efficiency, high stability for 6 cyclic potential scans and satisfactory reproducibility for 7 repeated tests. These results demonstrated the proposed 3D dual-modal ECL-biosensor for biomarkers detection had a great potential in clinical diagnostics, promoting the application in biomedical researching and POCT. [Display omitted] 1 A novel hybrid 3D copper-based nanomaterial (Cu-Flo.) coupled with gold nanoparticles (Cu-Flo.@AuNPs) was realized excellent catalytic-ability towards glucose. 2. Colorimetric and electrochemiluminescence (ECL) bioassays were performed based on the in-situ H 2 O 2 -generation luminol-system. 3. The blocking and direct catalytic assays showed an ultra-sensitivity for AFP and glucose detection simultaneously. 4. A promising nanozyme Cu-Flo. NMs overcomed the disadvantage of low-durability and instability for natural enzyme. [ABSTRACT FROM AUTHOR]