Emerging Combination of Hydrogel and Electrochemical Biosensors.

Electrochemical sensors are among the most promising technologies for biomarker research, with outstanding sensitivity, selectivity, and rapid response capabilities that make them important in medical diagnostics and prognosis. Recently, hydrogels have gained attention in the domain of electrochemical biosensors because of their superior biocompatibility, excellent adhesion, and ability to form conformal contact with diverse surfaces. These features provide distinct advantages, particularly in the advancement of wearable biosensors.

Leucine zipper-based SAIM imaging identifies therapeutic agents to disrupt the cancer cell glycocalyx for enhanced immunotherapy.

The abnormally thick glycocalyx of cancer cells can provide a physical barrier to immune cell recognition and effective immunotherapy. Here, we demonstrate an optical method based on Scanning Angle Interference Microscopy (SAIM) for the screening of therapeutic agents that can disrupt the glycocalyx layer as a strategy to improve anti-cancer immune responses. We developed a new membrane labeling strategy utilizing leucine zipper pairs to fluorescently mark the glycocalyx layer boundary for precise and robust measurement of glycocalyx thickness with SAIM.

Specific Degradation of the Mucin Domain of Lubricin in Synovial Fluid Impairs Cartilage Lubrication.

Progressive cartilage degradation, synovial inflammation, and joint lubrication dysfunction are key markers of osteoarthritis. The composition of synovial fluid (SF) is altered in OA, with changes to both hyaluronic acid and lubricin, the primary lubricating molecules in SF. Lubricin's distinct bottlebrush mucin domain has been speculated to contribute to its lubricating ability, but the relationship between its structure and mechanical function in SF is not well understood.

Deciphering Oxygen-Independent Augmented Photodynamic Oncotherapy by Facilitating the Separation of Electron-Hole Pairs.

Developing Type-I photosensitizers provides an attractive approach to solve the dilemma of inadequate efficacy of photodynamic therapy (PDT) caused by the inherent oxygen consumption of traditional Type-II PDT and anoxic tumor microenvironment. The challenge for the exploration of Type-I PSs is to facilitate the electron transfer ability of photosensitization molecules for transforming oxygen or HO to reactive oxygen species (ROS). Herein, we propose an electronic acceptor-triggered photoinduced electron transfer (a-PET) strategy promoting the separation of electron-hole pairs by marriage of two organic semiconducting molecules of a non-fullerene scaffold-based photosensitizer and a perylene diimide that significantly boost the Type-I PDT pathway to produce plentiful ROS, especially, inducing 3.

Recombinant Production of Glycoengineered Mucins in HEK293-F Cells.

Recombinant mucins are attractive polymeric building blocks for new biomaterials, biolubricants, and therapeutics. Advances in glycoengineered host cell systems now enable the recombinant production of mucins with tailored O-glycan side chains, offering new opportunities to tune the functionality of mucins and investigate the biology of specific O-glycan structures. Here, we provide a protocol for the scalable production of glycoengineered mucins and mucin-like glycoproteins in suspension-adapted HEK293-F cells.

Size-selective adhesion of calcium oxalate monohydrate crystals to lipid membranes.

The retention of calcium oxalate monohydrate (COM) crystals on cell membranes is pivotal in kidney stone formation. However, the mechanisms underlying COM attachment to neutral lipid membranes remain unclear. In this study, we demonstrate that COM exhibits size-selective adhesion to fluid lipid membranes composed of lipids with distinct sizes.

Atomically Site Synergistic Effects of Dual-Atom Nanozyme Enhances Peroxidase-like Properties.

Pursuing effective and generalized strategies for modulating the electronic structures of atomically dispersed nanozymes with remarkable catalytic performance is exceptionally attractive yet challenging. Herein, we developed a facile "formamide condensation and carbonization" strategy to fabricate a library of single-atom (M-NC; 6 types) and dual-atom (M/M-NC; 13 types) metal-nitrogen-carbon nanozymes (M = Fe, Co, Ni, Mn, Ru, Cu) to reveal peroxidase- (POD-) like activities. The FeCo-NC dual-atom nanozyme with Fe-N/Co-N coordination displayed the highest POD-like activity.

Photoinduced Electron Transfer Modulated Photoelectric Signal: Toward an Organic Small Molecule-Based Photoelectrochemical Platform for Formaldehyde Detection.

Photoelectrochemical (PEC) sensing has been rapidly evolving in recent years, while the introduction of small molecules with specific recognition functions into the sensing interface remains a nascent area of study. In this work, we reported a PEC biosensor for formaldehyde (FA) detection based on photoinduced electron transfer (PET)-gated electron injection between organic small molecules and inorganic semiconducting substrates. Specifically, an FA-responsive probe (NA-FA-COOH) and TiO nanoarrays were integrated to construct a PEC platform (NFC/TiO) via a coordination bond.

Microelectromechanical Microsystems-Supported Photothermal Immunoassay for Point-of-Care Testing of Aflatoxin B1 in Foodstuff.

Accurate identification of acutely toxic and low-fatality mycotoxins on a large scale in a quick and cheap manner is critical for reducing population mortality. Herein, a portable photothermal immunosensing platform supported by a microelectromechanical microsystem (MEMS) without enzyme involvement was reported for point-of-care testing of mycotoxins (in the case of aflatoxin B, AFB) in food based on the precise satellite structure of Au nanoparticles. The synthesized Au nanoparticles with a well-defined, graded satellite structure exhibited a significantly enhanced photothermal response and were coupled by AFB antibodies to form signal conversion probes by physisorption for further target-promoted competitive responses in microplates.

Convergent Approaches to Delineate the Metabolic Regulation of Tumor Invasion by Hyaluronic Acid Biosynthesis.

Metastasis is the leading cause of breast cancer-related deaths and is often driven by invasion and cancer-stem like cells (CSCs). Both the CSC phenotype and invasion are associated with increased hyaluronic acid (HA) production. How these independent observations are connected, and which role metabolism plays in this process, remains unclear due to the lack of convergent approaches integrating engineered model systems, computational tools, and cancer biology.

Point-of-Care Immunoassay Based on a Multipixel Dual-Channel Pressure Sensor Array with Visual Sensing Capability of Full-Color Switching and Reliable Electrical Signals.

The point-of-care (POC) method with affordability and portability for the sensitive detection of biological substances is an emerging topic in rapid disease screening and personalized medicine. In this work, we demonstrated a diverse responsive platform based on a dual-channel pressure sensor (DCPS). The DCPS had a multilayer flexible architecture consisting of a photonic hydrogel with chromatic transitions and a piezoresistive pressure sensor as the electrical data transmission unit, both of which had the property of pressure-induced mechanical stimulus feedback.

Dual-Signaling Photoelectrochemical Biosensor Based on Biocatalysis-Induced Vulcanization of BiMoO Nanosheets.

A magnetic-assisted photoelectrochemical (PEC) and colorimetric (CL) dual-modal biosensing platform with high precision was established to monitor prostate-specific antigen (PSA) based on BiMoO nanosheets (BMO) by coupling the aptamer-guided hybridization chain reaction (HCR) with the hydrolysate-induced vulcanization reaction of BiMoO nanosheets. Upon addition of PSA, trigger DNA (tDNA) was released by the interaction between the target analyte and the aptamer and then further hybridized with anchor DNA (aDNA) conjugated on magnetic beads (MBs). The as-released tDNA initiated the target-assisted HCR in the presence of two alternating hairpin sequences (Bio-H1 and Bio-H2) to produce nicked long double-stranded DNA on the surface of MBs, where numerous alkaline phosphatase (ALP) enzymes could assemble with MBs through the biotin-avidin reaction, resulting in the hydrolysis of sodium thiophosphate (TP) to HS.

Contactless Photoelectrochemical Biosensor Based on the Ultraviolet-Assisted Gas Sensing Interface of Three-Dimensional SnS Nanosheets: From Mechanism Reveal to Practical Application.

This work reports a contactless photoelectrochemical biosensor based on an ultraviolet-assisted gas sensor (UV-AGS) with a homemade three-dimensional (3D)-SnS nanosheet-functionalized interdigitated electrode. After rigorous examination, it was found that the gas responsiveness accelerated and the sensitivity increased using the UV irradiation strategy. The effects of the interlayer structure and the Schottky heterojunction on the gas-sensitive response of O and NH under UV irradiation were further investigated theoretically by 3D electrostatic field simulations and first-principles density functional theory to reveal the mechanism.

Luminescent Composite Carbon/SiO Structures: Synthesis and Applications.

Luminescent carbon nanostructures (CNSs) have attracted great interest from the scientific community due to their photoluminescent properties, structural features, low toxicity, and a great variety of possible applications. Unfortunately, a few problems hinder their further development. These include the difficulties of separating a mixture of nanostructures after synthesis and the dependence of their properties on the environment and the aggregate state.

Photoelectrochemical bioanalysis of microRNA on yolk-in-shell Au@CdS based on the catalytic hairpin assembly-mediated CRISPR-Cas12a system.

This work reports on the proof-of-concept of a photoelectrochemical (PEC) biosensor with a horseradish peroxidase-single stranded DNA-encoded magnetic bead (MB-ssDNA-HRP) signal probe cleaved by the catalytic hairpin assembly (CHA)-mediated clustered regularly interspaced short palindromic repeats (CRISPR)-Cas12a system for the quantification of microRNA (miR-21) by using yolk-in-shell Au@CdS as a photoactive material.

Pressure-Based Immunoassays with Versatile Electronic Sensors for Carcinoembryonic Antigen Detection.

Pressure-based immunoassays have been studied for point-of-care testing for which increasing the sensitivity is still a challenge. In this study, we described an enhanced pressure-based immunoassay with a versatile electronic sensor for the sensitive biological analysis. The versatile electronic sensor had multifunctional sensing capabilities with temperature and pressure recording.

Pressure-Based Bioassay Perceived by a Flexible Pressure Sensor with Synergistic Enhancement of the Photothermal Effect.

An effective signal amplification strategy based on temperature-amplification synergistic pressure was designed for the sensitive detection of carcinoembryonic antigen (CEA) by using a noncontact point-of-care testing (POCT) aptasensor with a flexible pressure sensor based on a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)-modified sponge (PEDOT:PSS-sponge). In the biological recognition system, target analyte triggered the release of platinum nanoparticle-labeled complementary DNA (Pt-cDNA) from CEA aptamer-conjugated magnetic beads. On the basis of the unique characteristics of platinum nanoparticles (e.

A polypyrrole-polydimethylsiloxane sponge-based compressible capacitance sensor with molecular recognition for point-of-care immunoassay.

A highly compressible and all-solid-state polydimethylsiloxane (PDMS) sponge-based flexible capacitance sensor modified with polypyrrole (PPy) was designed as the signal readout for the sensitive immunoassay of prostate-specific antigen (PSA). This system mainly consisted of a compressible capacitance sensor, immunoreaction protocol and gas delivery channel. The capacitance sensor was connected to a single microplate by a syringe, whereas the immunoreaction was carried out in the microplate.

Distance-dependent visual fluorescence immunoassay on CdTe quantum dot-impregnated paper through silver ion-exchange reaction.

A paper-based visual fluorescence immunoassay is presented for the detection of matrix metalloproteinase-7 (MMP7) that is related to renal cancer. The method is based on the distance-dependent fluorescence quenching of CdTe quantum dots (QDs) on a nitrocellulose membrane by Ag following a sandwich-type immunoreaction on microtiter wells using silver nanoparticle (AgNP)-labeled secondary antibody- and primary antibody-coated microtiter wells. The silver nanoparticles captured in the well are dissolved with HNO, while the quenching effect of QDs is based on silver ion-exchange reaction under 365-nm excitation light irradiation.

Litmus-Body: A Molecularly Targeted Sensor for Cell-Surface pH Measurements.

Precise pH measurements in the immediate environment of receptors is essential for elucidating the mechanisms through which local pH changes associated with diseased phenotypes manifest into aberrant receptor function. However, current pH sensors lack the ability to localize and target specific receptor molecules required to make these measurements. Herein we present the Litmus-body, our recombinant protein-based pH sensor, which through fusion to an anti-IgG nanobody is capable of piggybacking on IgG antibodies for molecular targeting to specific proteins on the cell surface.

Alterations in Gut Microbiota of Gestational Diabetes Patients During the First Trimester of Pregnancy.

Dysbiosis of human gut microbiota is associated with a wide range of metabolic disorders, including gestational diabetes mellitus (GDM). Yet whether gut microbiota dysbiosis participates in the etiology of GDM remains largely unknown. Our study was initiated to determine whether the alternations in gut microbial composition during early pregnancy linked to the later development of GDM, and explore the feasibility of microbial biomarkers for the early prediction of GDM.

Self-Powered Temperature Sensor with Seebeck Effect Transduction for Photothermal-Thermoelectric Coupled Immunoassay.

A self-powered temperature sensor based on Seebeck effect transduction was designed for photothermal-thermoelectric coupled immunoassay of α-fetoprotein (AFP). In this system, glucose oxidase (GOx)-conjugated detection antibody was first captured onto the microplate by target-induced sandwich-type immunoreaction. Thereafter, the as-generated hydrogen peroxide via the GOx-glucose system oxidized 3,3',5,5'-tetrametylbenzidine (TMB) into photothermal product oxidized TMB (ox-TMB).