4‑Amino-1-(3-mercapto-propyl)-pyridine Hexafluorophosphate Ionic Liquid Functionalized Gold Nanoparticles for IgG Immunosensing Enhancement

A novel ionic liquid, 4-amino-1-(3-mercapto-propyl)-pyridine hexafluorophosphate (AMPPH), was successfully synthesized and characterized. Subsequently, AMPPH was used as a functional monomer to fabricate AMPPH-modified gold nanoparticles (AMPPH–AuNPs) via a one-pot synthesis method. The as-prepared AMPPH–AuNPs were confirmed with transmission electron microscopy and X-ray photoelectron spectroscopy. AMPPH–AuNPs were used to construct a biocompatible interface to immobilize rabbit anti-human IgG (anti-HIgG) onto a glassy carbon electrode (GCE) surface, followed by a cross-linking step with glutaraldehyde to fabricate an anti-HIgG–AMPPH–AuNPs/GCE. The nonspecific binding sites were enclosed with bovine serum albumin (BSA) to develop an immunosensor for human IgG. Electrochemical impedance spectroscopy, cyclic voltammetry and differential pulse voltammetry were used to investigate the electrochemical properties of the developed immunosensor. The results indicate that AMPPH–AuNPs can improve the immunosensing performance. The current response of the immunosensor was found linearly related to human IgG concentration in the range of 0.1–5.0 ng mL^–1 and 5.0–100.0 ng mL^–1. The detection limit is estimated to be 0.08 ng mL^–1 (<i>S</i>/<i>N</i> = 3). The obtained immunosensor was successfully applied to the analysis human IgG immunoglobulin in human serum, and the results were well consistent with ELISA method

White-Light-Exciting, Layer-by-Layer-Assembled ZnCdHgSe Quantum Dots/Polymerized Ionic Liquid Hybrid Film for Highly Sensitive Photoelectrochemical Immunosensing of Neuron Specific Enolase

ZnCdHgSe quantum dots (QDs) functionalized with <i>N</i>-acetyl-l-cysteine were synthesized and characterized. Through layer-by-layer assembling, the ZnCdHgSe QDs was integrated with a polymerized 1-decyl-3-[3-pyrrole-1-yl-propyl]­imidazolium tetrafluoroborate (PDPIT) ionic liquid film modified indium tin oxide (ITO) electrode to fabricated a photoelectrochemical interface for the immobilization of rabbit antihuman neuron specific enolase (anti-NSE). After being treated with glutaraldehyde vapor and bovine serum albumin successively, an anti-NSE/ZnCdHgSe QDs/PDPIT/ITO sensing platform was established. Simplely using a white-light LED as an excitation source, the immunoassay of neuron specific enolase (NSE) was achieved through monitoring the photocurrent variation. The polymerized ionic liquid film was demonstrated to be an important element to enhance the photocurrent response of ZnCdHgSe QDs. The anti-NSE/ZnCdHgSe QDs/PDPIT/ITO based immunosensor presents excellent performances in neuron specific enolase determination. The photocurrent variation before and after being interacted with NSE exhibits a good linear relationship with the logarithm of its concentration (log <i>c</i>_NSE) in the range from 1.0 pg mL^–1 to 100 ng mL^–1. The limit of detection of this immunosensor is able to reach 0.2 pg mL^–1 (<i>S</i>/<i>N</i> = 3). The determination of NSE in clinical human sera was also demonstrated using anti-NSE/ZnCdHgSe QDs/PDPIT/ITO electrode. The results were found comparable with those obtained by using enzyme-linked immunosorbent assay method

Elevated Serum Levels of Circulating Immunoinflammation-Related Protein Complexes Are Associated with Cancer

Disease-specific immune response-related protein complexes in the bloodstream are associated with disease status. We used proteomic technologies to screen novel circulating immunoinflammation-related protein complexes (IIRPCs) and to evaluate their diagnostic accuracy. The discovery study included 96 gastric cancer patients and 83 healthy controls and was designed to isolate and identify the IIRPCs. Then an independent validation study including 1366 patients with lung, colorectal, pancreatic, gastric, or thyroid cancer, 141 patients with other types of cancer, 376 patients with benign lung, colorectal, pancreatic, gastric, or thyroid diseases, and 3707 healthy controls was performed. We observed seven major patterns of the IIRPCs and confirmed the IIRPCs as personalized biomarkers of cancers. The levels of the IIRPCs were significantly increased in cancer patients compared with controls and benign patients (<i>p</i> < 0.0001). Each of the IIRPCs (a2 to a4, a6, a7, and b3 to b5) shows excellent discriminating power for lung, colorectal, pancreatic, and gastric cancer, with the areas under the receiver operating characteristic curves (AUCs) from 0.95 to 0.99 (95% CIs 0.91–1.00), and for thyroid cancer, with the AUCs from 0.87 to 0.96 (95% CIs 0.80–0.98). The IIRPCs can be used as a novel type of broad-spectrum and supramolecular biomarker for personalized cancer diagnosis

Machine Learning-Assisted High-Throughput Strategy for Real-Time Detection of Spermine Using a Triple-Emission Ratiometric Probe

In this study, we designed and fabricated a spermine-responsive triple-emission ratiometric fluorescent probe using dual-emissive carbon nanoparticles and quantum dots, which improve the sensor’s accuracy and reduce interfering environmental effects. The probe is advantageous for the proportionate detection of spermine because it has good emission resolution, and the maximum points of the two emission peaks differ by 95 nm. As a proof of concept, cuvettes and a 96-well plate were combined with a smartphone and YOLO series algorithms to accomplish real-time, visual, and high-throughput detection of seafood and meat freshness. In addition, the reaction mechanism was verified by density functional theory and fundamental characterizations. Upon exposure to different amounts of spermine, the intensity of the fluorescent probe changed linearly, and the fluorescent color shifted from yellow-green to red, with a limit of detection of 0.33 μM. To enable visual identification of food-originated spermine, a hydrogel-based visual sensing platform was successfully developed utilizing the triple-emission fluorescent probe. Consequently, spermine could be identified and quantified without complicated equipment