Talanta最新文献

The development of new technologies for at-home self-testing holds promising potential for chronic disease management and monitoring. Recently, microfluidic paper-based analytical devices (μPADs) have demonstrated versatile capabilities for point-of-care testing (POCT). Sialic acid (SA), closely linked to the modification of glycoproteins in vivo, serves as an important biomarker for home-based self-testing. In this study, a novel paper-based microfluidic biomimetic chip (FP@Zr-BA@MIP) was successfully developed using boronate affinity surface imprinting technology. This chip exhibited a high adsorption capacity (Q_e = 352.83 mg g^-1), good selectivity (imprinting factor, IF = 3.67), rapid detection efficiency (within 30 min), and excellent anti-interference capability against sialic acid. Additionally, a visual sensing system was integrated into the platform, enabling rapid, visual, and quantitative analysis of SA. A linear range of 0.1-25 mg L^-1 was achieved, with the limit of detection (LOD) and limit of quantitation (LOQ) as low as 0.066 mg L^-1 and 0.21 mg L^-1, respectively. The synergistic combination of the simple operational features inherent to paper-based microfluidics and the intuitive readout advantage of visual sensing significantly enhanced the simplicity and overall efficiency of the detection process. This design offers a novel approach for realizing a POCT platform for non-invasive analysis of SA.

Tuberculosis is a major infectious disease with high global mortality, and its first-line drugs, rifampicin (RIF) and isoniazid (INZ), are associated with serious adverse effects and public health risks when improperly administered, due to toxicity, environmental residues, and the potential induction of mycobacterial resistance. Low-cost, rapid analytical methods with simple instrumentation, particularly electrochemical approaches using screen-printed carbon electrodes (SPCE), are highly desirable for detecting these drugs. In this work, a novel electrochemical method for the simultaneous quantification of RIF and INZ was developed employing linear sweep voltammetry (LSV) as the analytical technique. As an electrochemical platform, a miniaturized and portable carbon-integrated substrate system was modified via drop-casting using a nanocomposite based on carbon black (CB) with cerium oxide (CeO₂), which was comprehensively characterized using structural, morphological, and electrochemical analyses. Importantly, this CB/CeO₂ material offered a drastic synergic effect for improving the electrochemical response of both antibiotics. The voltammetric strategy provided wide linear ranges for INZ (3.66 to 343.0 μmol L^-1) and RIF (0.611 to 57.3 μmol L^-1) with limits of detection of 0.638 μmol L^-1 and 0.0390 μmol L^-1, respectively. In addition, the sensor exhibited excellent fabrication reproducibility with RSD <4.76 %, as well as high selectivity for the analyte, making SPCE/CB/CeO₂ applicable to tap water, human urine, and synthetic human serum, with satisfactory recoveries ranging from 96.9 to 106 % demonstrating its potential for monitoring aquatic and biological matrices.

Heavy metals, such as Pb²⁺ and Cd²⁺, pose significant risks to human health and ecosystems due to their toxicity and bioaccumulation. This study presents a novel electrochemical sensor utilizing a hydrazine-functionalized metal-organic framework (MOF-Hydrazine) modified glassy carbon electrode for the simultaneous detection of Pb²⁺ and Cd²⁺ ions in food and environmental samples. The MOF-Hydrazine composite, synthesized via a solvothermal method, exhibits high surface area, tunable porosity, and enhanced electrocatalytic properties, enabling superior sensitivity and selectivity. Square wave anodic stripping voltammetry (SWASV) was employed, optimized through Plackett-Burman and Box-Behnken designs, to achieve detection limits of 0.0005 nmol L^-1 for Pb²⁺ and 0.004 nmol L^-1 for Cd²⁺, surpassing many conventional methods. The sensor demonstrated excellent linearity (0.002-200 nmol L^-1 for Pb²⁺, 0.01-100 nmol L^-1 for Cd²⁺), repeatability (RSD <2.43%), and stability (retaining >94% response after four weeks). Real-sample analysis of food and water matrices showed results consistent with ICP-OES, with no significant interference from common ions. This cost-effective, rapid, and sensitive sensor offers a sustainable alternative for trace metal monitoring, with potential for portable, on-site applications in environmental and food safety assessments.

Interstitial skin fluid (ISF) is recognized as a promising source of biomarkers, yet point-of-care testing (POCT) based on ISF remains hindered by multiple challenges. To address these issues, specifically improving ISF extraction efficiency and enabling practical POCT analysis, this study developed a painless hollow microneedles (MNs) module. The module connects to a syringe via a flexible tube to generate negative pressure, with the syringe scale directly determining the pressure magnitude applied for ISF extraction. Additionally, grooves at the bottom of the MNs module can accommodate diverse test strips, facilitating the detection of multiple biomarkers. This design features simplicity and ease of operation. It was validated through both in vitro and in vivo experiments: in vitro detection of glucose, pH, and alcohol within 3 min; and in vivo extraction of 10.2 (±1.9) mg of ISF. Notably, this module design eliminates the need for ISF recovery steps or specialized equipment for subsequent analysis. These results demonstrate the design's potential for applications in POCT and personalized medicine.

Malathion (MLT) is an organophosphate insecticide with well-defined toxicity to the human body. Both short-term exposure to high doses and long-term exposure to low doses can impair human health. In this study, we developed a novel colorimetric and photothermal method for the detection of MLT using aptamer (Apt)-conjugated FeCu-metal-organic framework (FeCu-MOF) loaded with gold nanoparticles (AuNPs). FeCu-MOF possesses peroxidase-like activity, enabling it to catalyze the oxidation of colorless 3,3',5,5'-tetramethylbenzidine (TMB). This reaction yields blue oxidized TMB (oxTMB), which generates detectable colorimetric and photothermal signals. The Apt binds specifically to MLT, thereby altering the catalytic activity of the nanozyme. This method capitalizes on the high catalytic efficiency of the nanozyme and the specific recognition capability of the Apt, enabling sensitive and selective detection of MLT. It also exhibits excellent selectivity against other interfering substances. When testing spiked samples, colorimetric detection yielded satisfactory results: recoveries ranged from 98.1% to 107.4%, with a relative standard deviation (RSD) below 3.3%. Additionally, the recovery rates of MLT determined via photothermal detection are reported herein, with recoveries ranging from 92.1% to 106.5% and RSDs less than 5.2%. Overall, this work provides a simple, rapid, and sensitive strategy for MLT detection, which holds significant potential for practical applications in food safety and environmental monitoring.

The discovery of antitumor components in complex natural medicine mixtures is often hampered by the time-consuming, labor-intensive, and poorly reproducible nature of conventional screening methods, which may also fail to adequately simulate physiological conditions. To address these limitations, a macroporous frit capillary electrophoresis (MFCE) method was established, in which tumor tissue, serving as the interaction phase, is physically intercepted by a macroporous frit formed from packed silica beads. This critical step ensures effective tissue interception and mass transfer. By detecting and analyzing key capillary electrophoretic parameters, tissue-compound interactions can be directly monitored, thereby enabling qualitative and quantitative analysis of the interactions between complex mixtures and tumor tissue. The MFCE was applied to qualitatively and quantitatively investigate the interactions between Aidi injection and A549 tumor tissue. Five interactive compounds were identified by integrating MFCE with CE-MS/MS analyses, and the results were consistent with previous reports, confirming the method's reliability. Subsequently, MFCE was used to evaluate the interactions of both ethyl acetate and water extracts of Xiao-Ai-Fei Honey Ointment with HT-29 tumor tissues. Integrated analysis using MFCE, CE-MS/MS, and LC-MS/MS identified four and five interacting compounds from the ethyl acetate and water extracts, respectively. Enabled by stable tissue immobilization and the optimized frit architecture, the binding kinetic parameters (k_d, K, k_a, k') for these compounds were quantified by non-linear chromatography. The biological relevance of these findings was confirmed through in vitro cell viability assays and in vivo xenograft models, which demonstrated that the identified interactive components possess potent antitumor activity, thereby validating the reliability and accuracy of the MFCE method. MFCE thus provides a rapid, reliable strategy to directly monitor tumor tissue-compound interactions, linking the method's design, operational principle, and biological relevance, thereby laying a foundation for multi-targeted anticancer compound discovery.

Thermal lens spectroscopy (TLS) is a highly sensitive, non-destructive photothermal method for detecting and quantifying light-absorbing species. We implemented a dual-beam configuration (focused pump, collimated probe, both propagating coaxially) operated in the transient regime. Quantification of Cr (VI) was performed via the Cr (VI)-1,5-diphenylcarbazide complex measured by Thermal lens spectroscopy at 532 nm. The calibration (0-5 mg L^-1) curve showed excellent linearity (R² > 0.997) with a limit of detection of 293 μg L^-1. We then assessed the performance of polymeric membranes containing graphene-oxide nanoparticles under continuous-flow filtration (initial concentration C₀ = 4 mg L^-1; total volume 35 mL), acquiring time-resolved adsorption curves from microvolume aliquots (200 μL) with negligible perturbation of the experiment. Two membrane types were compared: (i) graphene oxide synthesized from obtaining graphite oxide following the modified Hummers' method and (ii) Commercial graphene oxide modified with surfactant to improve its interlayer spacing. Both membranes achieved rapid adsorption, reaching equilibrium within 20-35 min, with the functionalized membrane equilibrating faster and exhibiting enhanced adsorption performance. The adsorption kinetics were analyzed using both pseudo-first-order (PFO) and pseudo-second-order (PSO) models, allowing a comparative evaluation of the kinetic descriptions while yielding consistent performance metrics for both membranes. These results demonstrate that Thermal lens spectroscopy provides a sensitive, resource-efficient readout to resolve adsorption kinetics and quantify removal efficiency and adsorption capacity using small membrane specimens and microvolumes, offering a practical route to characterize and optimize graphene-oxide-based polymer membranes for water remediation under realistic flow conditions.

The inherently low phase ratio and limited surface capacity of open-tubular capillary electrochromatography (OT-CEC) significantly restrict its efficiency in enantioseparation. To overcome this limitation, we developed a rigid-flexible composite interface strategy to construct a high-efficiency chiral ligand-exchange CEC (CLE-CEC) column. A uniform nanocrystalline UiO-66-NH₂ layer was in situ grown on the capillary inner wall to serve as a high-surface-area rigid scaffold, followed by the covalent immobilization of L-arginine (L-Arg) as a flexible chiral ligand. This composite architecture combines the structural stability of metal-organic frameworks (MOFs) with the stereochemical selectivity of amino acid ligands. The dense MOF scaffold effectively increases the specific surface area and ligand loading capacity of the stationary phase, thereby facilitating efficient Zn(II)-mediated ternary complexation for chiral recognition. Validating this design, the UiO-66-NH-L-Arg@capillary column achieved baseline separation for seven pairs of Dns-D,L-AAs, with resolution factors reaching up to 2.56. The column exhibited satisfactory repeatability and good operational stability. Furthermore, the practicability of this method was demonstrated by its successful application in the kinetic monitoring of L-alanine dehydrogenase, providing a robust micro-separation tool for precise bioanalysis.

Chromatography is a cornerstone methodology employed for quality evaluation of traditional Chinese medicine (TCM). However, the complexity of chromatographic data, where signals from multiple compounds overlap and interfere, often impedes the accurate identification of chemically significant features. This study proposed an integrated approach that combines multidimensional chromatographic fingerprinting with machine learning to trace the molecular origins of characteristic compounds in a representative TCM formula, Fufang E'jiao Jiang (FEJ). Following comprehensive chemical profiling, we constructed multi-dimensional datasets from chromatographic fingerprints, including TLC and LC-HRMS, with each dataset encompassing over 1700 features derived from retention time, m/z, and RGB values. Machine learning algorithms, such as random forest, were employed to select discriminative features, leading to the identification of 5 patterns in FEJ and 7 patterns in its intermediate products, primarily identified as ginsenosides. A simulation model further verified the significance of these features, showing that a single compound's chromatographic spot could effectively represent sample characteristics. We also introduced modified entropy values and obstacle factors to evaluate and weight the selected features. As a result, lobetyolin and ginsenoside Rf were recognized as key quality-related markers in FEJ and its intermediates, respectively. Experimental verification showed that this method can effectively deconvolute overlapping chromatographic signals and identify key quality-related features, providing an efficient and scalable computational framework for quality control in complex systems. In summary, this strategy is based on a general data structure and modular algorithm design, and hopefully to be applied to any sample system with complex chromatographic fingerprints (such as drug, environmental or food samples), without relying on specific domain knowledge.

A novel loose-multilayer polydimethylsiloxane/reduced graphene oxide composite (lmPDMS/rGO) was synthesized and immobilized onto a stainless steel wire to fabricate a solid-phase microextraction (SPME) fiber. The fiber exhibited a uniform multilayer structure, high thermal stability, mechanical robustness, and excellent electrical conductivity. It also demonstrated outstanding durability, remaining effective for up to 150 uses. Moreover, the fiber showed remarkable extraction efficiency for amphetamine-type stimulants (ATSs) in urine samples under an applied electric field. Analyte separation and quantification were performed using gas chromatography with a nitrogen phosphorus detector. Key extraction parameters (applied voltage, extraction time, stirring speed, and pH) were systematically optimized. Under the optimized conditions, calibration curves (5-500 ng L^-1) showed coefficients of determination >0.990, with relative recoveries of 82 %-105 %. Limits of detection (S/N = 3) and quantification (S/N = 10) ranged from 0.5 to 2.7 ng L^-1 and 1.8-9.1 ng L^-1, respectively. Intra- and inter-fiber RSDs were 3.9 %-6.2 % and 4.2 %-10.7 %, respectively. This study offers a promising strategy for designing functional PDMS-based composites with well-defined structure-performance relationships for enhanced SPME applications.