Antibacterial Properties of PCL@45s5 Composite Biomaterial Scaffolds Based on Additive Manufacturing.

This study focuses on the development of polymer-bioglass composite bone scaffolds for the treatment of bone defects. PCL particles and 45s5 bioglass powder were employed as raw materials to fabricate PCL/45s5 composite wires with mass fractions of 5 wt%, 10 wt%, and 20 wt% via the twin-screw extrusion method. A cylindrical porous model was established using 3D modeling software, and a porous composite scaffold was constructed through the melt deposition manufacturing process.

Laser-induced CdS/TiO/graphene dual photoanodes for ratiometric self-powered photoelectrochemical sensor: an innovative approach for aflatoxin B1 detection.

A ratiometric self-powered photoelectrochemical sensor based on laser direct writing technology was constructed to address the problem that the conventional single-signal detection mode was susceptible to the influence of instrumentation and environmental factors, which interfered with the detection results. Laser-induced CdS/TiO/Graphene was prepared as dual photoanodes (PA1 and PA2), which were controlled by multiplexed switches to form a photocatalytic fuel cell with Pt cathode. By modifying the aptamer of aflatoxin B1 (AFB1) on the photoanode surface, the target was specifically captured to the electrode surface to form a biological complex, which increased the steric hindrance and affected the electron transfer, thus reducing the output signal of the sensor.

Foldable paper-based photoelectrochemical biosensor based on etching reaction of CoOOH nanosheets-coated laser-induced PbS/CdS/graphene for sensitive detection of ampicillin.

Timely and rapid detection of antibiotic residues in the environment is conducive to safeguarding human health and promoting an ecological virtuous cycle. A foldable paper-based photoelectrochemical (PEC) sensor was successfully developed for the detection of ampicillin (AMP) based on glutathione/zirconium dioxide hollow nanorods/aptamer (GSH@ZrO HS@apt) modified cellulose paper as a reactive zone with laser direct-writing lead sulfide/cadmium sulfide/graphene (PbS/CdS/LIG) as photoelectrode and cobalt hydroxide (CoOOH) as a photoresist material. Initially, AMP was introduced into the paper-based reaction zone as a biogate aptamer, which specifically recognized the target and then left the ZrO HS surface, releasing glutathione (GSH) encapsulated inside.

A laser-induced zinc oxide/graphene photoelectrode for a photocurrent-polarity-switching photoelectrochemical biosensor with bipedal DNA walker amplification.

A photocurrent-polarity-switching photoelectrochemical (PEC) biosensor was developed for the ultrasensitive detection of tobramycin (TOB) through bipedal DNA walker amplification with hemin-induced photocurrent-polarity-switching using a laser-induced zinc oxide/graphene (ZnO/LIG) photoelectrode. Specifically, the ZnO/LIG photoelectrode was synthesized by a laser direct writing (LDW) technique. In the presence of TOB, it reacted with HP1 and HP2 and the DNA walker response was activated to form a stable hemin/G-quadruplex.

Portable glucose sensing analysis based on laser-induced graphene composite electrode.

In this work, a portable electrochemical glucose sensor was studied based on a laser-induced graphene (LIG) composite electrode. A flexible graphene electrode was prepared using LIG technology. Poly(3,4-ethylene dioxythiophene) (PEDOT) and gold nanoparticles (Au NPs) were deposited on the electrode surface by potentiostatic deposition to obtain a composite electrode with good conductivity and stability.

Contactless photoelectrochemical biosensors based on hierarchical MXene/BiS nanosheets with the branched hybridization chain reaction.

Ethyl carbamate, a substance frequently occurring in fermented foods, seriously affects people's health; however, poor sensitivity constrains the development of ethyl carbamate sensors. In this work, hierarchical BiS/MXene nanosheets were synthesized using a hydrothermal method, and experimentally their coupled UV light is an efficient NH sensing material. Meanwhile, the density functional theory (DFT) confirms that the MXene/BiS nanosheet interface has an excellent ability to adsorb NH, resulting in a change of photocurrent.

MXene-TiO-based photocatalytic fuel cell with bioresponsive controlled glucose release system: An innovative mode for Ochratoxin A detection.

Self-powered photocatalytic fuel cell (PFC)-based sensors incorporating bioelement recognition with fuel concentration-dependent output power have been developed for electrochemical analysis, but most involve poor energy conversion efficiency and are unsuitable for routine use. Herein, a self-powered and self-checking PFC bioanalysis platform under visible light for ultrasensitive screening of Ochratoxin A (OTA) was designed. Specifically, the self-powered photocatalytic fuel cell-based sensor was comprised of a photoanode fabricated with MXenes (TiC)-TiO and a cathode modified with Prussian blue (PB).

Chiral covalent organic framework incorporated organic polymer monolithic capillary column for enantioseparations.

A chiral covalent organic framework was synthesized, characterized, and incorporated into organic polymer monolithic capillary columns to provide chiral stationary phases for enantioseparations. The prepared monolithic capillary columns were characterized by scanning electron microscopy and elemental analysis. To obtain better enantioseparations, the columns' preparation conditions, and enantioseparation conditions were optimized.

Smartphone-Based Photoelectrochemical Immunoassay with CoS@ZnInS for Point-of-Care Diagnosis of Breast Cancer Biomarker.

Photoelectrochemical immunoassays incorporating specific antigen-antibody recognition reactions with the photon-electron conversion capabilities of photocatalysts have been developed for biomarker detection, but most involve bulky and expensive equipment and are unsuitable for point-of-care testing. Herein, a portable smartphone-based photoelectrochemical immunoassay was innovatively designed for the on-site detection of breast cancer biomarkers (human epidermal growth factor receptor 2; HER2). The system consists of a split-type immunoassay mode, disposable screen-printed electrode covered with hierarchical CoS@ZnInS heterostructures, an integrated circuit board, and a Bluetooth smartphone equipped with a specially designed app.

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.

TiC MXene-anchored photoelectrochemical detection of exosomes by fabrication of CdS nanoparticles with enzyme-assisted hybridization chain reaction.

Exosomes that carry large amounts of tumor-specific molecular information have been identified as a potential non-invasive biomarker for early warning of cancer. In this work, we reported an enzyme-assisted photoelectrochemical (PEC) biosensor for quantification of exosomes based on the synthesis of TiC MXene/CdS composites with magnetic separation technology and hybridization chain reaction (HCR). First, exosomes were specifically bound between aptamer-labeled magnetic beads (CD63-MBs) and a cholesterol-labeled DNA anchor.

Nanostructure-based photoelectrochemical sensing platforms for biomedical applications.

As a newly developed and powerful analytical method, the use of photoelectrochemical (PEC) biosensors opens up new opportunities to provide wide applications in the early diagnosis of diseases, environmental monitoring and food safety detection. The properties of diverse photoactive materials are one of the essential factors, which can greatly impact the PEC performance. The continuous development of nanotechnology has injected new vitality into the field of PEC biosensors.

A chemiresistive thin-film translating biological recognition into electrical signals: an innovative signaling mode for contactless biosensing.

An innovative signaling mode in which a chemiresistive thin-film electrode monitors the specific gaseous component that results from a biological recognition event to indirectly detect targets in the liquid phase is developed for highly-efficient contactless biosensing. This signaling mode may open a new horizon in designing robust biosensing devices for bioanalysis.

Dual-Channel Photoelectrochemical Ratiometric Aptasensor with up-Converting Nanocrystals Using Spatial-Resolved Technique on Homemade 3D Printed Device.

A near-infrared light-activated ratiometric photoelectrochemical aptasensor was fabricated for detection of carcinoembryonic antigen (CEA) coupling with upconversion nanoparticles (UCNPs)-semiconductor nanocrystals-based spatial-resolved technique on a homemade 3D printing device in which a self-regulating integrated electrode was designed for dual signal readout. The as-prepared NaYF:Yb,Er UCNPs@CdTe nanocrystals were initially assembled on two adjacent photoelectrodes, then CEA aptamer 1 (A) and capture DNA (CA) were modified onto two working photoelectrodes (WP and WP) through covalent binding, respectively, and then gold nanoparticle-labeled CEA aptamer 2 (Au NP-A) was immobilized on the surface of functional WP for the formation of double-stranded DNA. Upon target CEA introduction, the various concentrations of CEA were captured on the WP, whereas the binding of the CEA with Au NP-A could be released from the WP thanks to the highly affinity of CEA toward A.

NaYF:Yb,Er Upconversion Nanotransducer with in Situ Fabrication of AgS for Near-Infrared Light Responsive Photoelectrochemical Biosensor.

An innovative near-infrared (NIR) light-driven photoelectrochemical (PEC) aptasensor was constructed for sensitive screening of carcinoembryonic antigen (CEA) on the basis of in situ formation of AgS nanoparticles on the NaYF:Yb,Er upconversion nanoparticles (UCNs), coupled with hybridization chain reaction (HCR) for the signal amplification. Utilization of UCN as the light nanotransducer could convert the NIR light into an applicable wavelength harvested by semiconductors. The multiemissions of NaYF:Yb,Er UCN could match well with the absorption characteristics of AgS.

Self-Referenced Smartphone Imaging for Visual Screening of HS Using Cu O-Polypyrrole Conductive Aerogel Doped with Graphene Oxide Framework.

Cu O-polypyrrole conductive aerogel loaded on graphene oxide framework (Cu O-PPy@GO) with a three-dimensional (3D) porous architecture was utilized for high-efficient visual screening of HS on a flexible paper substrate. The detectable signal was acquired on a portable smartphone by using a self-referenced imaging platform equipped with the light emitting diode (LED) accompanying an image processing. As a proof-of-concept, Cu O-PPy@GO aerogel-based sensing strategy was also developed for NaS detection and egg spoilage monitoring.

Plasmonic resonance enhanced photoelectrochemical aptasensors based on g-CN/BiMoO.

An in-depth exploration associated with the localized surface plasmon resonance (LSPR) effect for plasmonic photoelectrochemistry (PEC) is beneficial for the development of high-efficiency biosensors. A novel phenomenon on the LSPR between g-C3N4/Bi2MoO6 and gold nanoparticles is investigated in a PEC aptasensing system under ultraviolet and visible light irradiation.

Plasmonic Enhancement Coupling with Defect-Engineered TiO: A Mode for Sensitive Photoelectrochemical Biosensing.

This work demonstrates that the photoelectric response of defect-engineered TiO modified with Au nanoparticles can be modulated by oxygen vacancy concentration and excitation wavelength. When strongly plasmonic Au nanoparticles are anchored to defect-engineered TiO by DNA hybridization, several times plasmonic enhancement of photocurrent occurs under 585 nm excitation, and it is employed as a novel signaling mode for developing an improved photoelectrochemical sensing platform. This signaling mode combined with exonuclease III-assisted target recycling amplification exhibits excellent analytical performance, which provides a novel photoelectrochemical detection protocol.

Near-Infrared-to-Ultraviolet Light-Mediated Photoelectrochemical Aptasensing Platform for Cancer Biomarker Based on Core-Shell NaYF:Yb,Tm@TiO Upconversion Microrods.

Titanium dioxide (TiO; as a potential photosensitizer) has good photocurrent performance and chemical stability but often exhibits low utilization efficiency under ultraviolet (UV) region excitation. Herein, we devised a near-infrared light-to-UV light-mediated photoelectrochemical (PEC) aptasensing platform for the sensitive detection of carcinoembryonic antigen (CEA) based on core-shell NaYF:Yb,Tm@TiO upconversion microrods by coupling with target-triggered rolling circle amplification (RCA). The upconversion microrods synthesized through the hydrothermal reaction could act as a photosensing platform to convert the near-infrared (near-IR) excitation into UV emission for generation of photoinduced electrons.

Cu-Doped SnO Nanograin/Polypyrrole Nanospheres with Synergic Enhanced Properties for Ultrasensitive Room-Temperature HS Gas Sensing.

The organic-inorganic nanohybrids are emerging as one of the most attractive sensing materials in the area of gas sensors and usually exhibit some advanced properties because of synergetic/complementary effects between organic molecules and inorganic components. This work demonstrates a novel class of organic-inorganic nanohybrids, Cu-doped SnO nanograin/poly pyrrole nanospheres, for the sensitive room-temperature HS gas sensing. Doping Cu in SnO nanograins remarkably enhances the surface potential barrier by tailoring surface defects.

Bioresponsive Release System for Visual Fluorescence Detection of Carcinoembryonic Antigen from Mesoporous Silica Nanocontainers Mediated Optical Color on Quantum Dot-Enzyme-Impregnated Paper.

An all-in-one paper-based analytical device (PAD) was successfully developed for visual fluorescence detection of carcinoembryonic antigen (CEA) on CdTe/CdSe quantum dot (QD)-enzyme-impregnated paper by coupling with a bioresponsive controlled-release system from DNA-gated mesoporous silica nanocontainers (MSNs). The assay was carried out in a centrifuge tube by using glucose-loaded MSNs with a CEA aptamer and a QD-enzyme-paper attached on the lid. Initially, single-strand complementary DNA to a CEA aptamer was covalently conjugated to the aminated MSN, and then glucose (enzyme substrate) molecules were gated into the pore with the help of the aptamer.

Semiautomated Support Photoelectrochemical Immunosensing Platform for Portable and High-Throughput Immunoassay Based on Au Nanocrystal Decorated Specific Crystal Facets BiVO Photoanode.

Photoelectrochemical (PEC) measurement has been developed rapidly for bioanalysis in recent years. However, the actual application for most existed PEC bioanalytical systems is still a challenge because the perfect solutions for sensing surface design, high-throughput detection, and portability are lacked. To successfully overcome these limitations and realize accurate, continuous screening and assessing on prognostic indicator of early stage cancer on the spot, an innovative and portable semiautomated support power-free photoelectrochemical (SP-PEC) immunosensing platform consisted with a miniature semiautomatic injection system and digital multimeter (DMM) readout is designed (prostate specific antigen, PSA, was used as the proof-of-concept analyte).

Hybridization chain reaction-based colorimetric aptasensor of adenosine 5'-triphosphate on unmodified gold nanoparticles and two label-free hairpin probes.

This work designs a new label-free aptasensor for the colorimetric determination of small molecules (adenosine 5'-triphosphate, ATP) by using visible gold nanoparticles as the signal-generation tags, based on target-triggered hybridization chain reaction (HCR) between two hairpin DNA probes. The assay is carried out referring to the change in the color/absorbance by salt-induced aggregation of gold nanoparticles after the interaction with hairpins, gold nanoparticles and ATP. To construct such an assay system, two hairpin DNA probes with a short single-stranded DNA at the sticky end are utilized for interaction with gold nanoparticles.

CdTe/CdSe quantum dot-based fluorescent aptasensor with hemin/G-quadruplex DNzyme for sensitive detection of lysozyme using rolling circle amplification and strand hybridization.

Lysozyme with a small monomeric globular enzymatic protein is part of the innate immune system, and its deficiency can cause the increased incidence of disease. Herein, we devise a new signal-enhanced fluorescence aptasensing platform for quantitative screening of lysozyme by coupling with rolling circle amplification (RCA) and strand hybridization reaction, accompanying the assembly of CdTe/CdSe quantum dots (QDs) and hemin/G-quadruplex DNzyme. Initially, target-triggered release of the primer was carried out from DNA duplex via the reaction of the aptamer with the analyte, and the released primer could be then utilized as the template to produce numerous repeated oligonucleotide sequences by the RCA reaction.

Enzymatic Oxydate-Triggered Self-Illuminated Photoelectrochemical Sensing Platform for Portable Immunoassay Using Digital Multimeter.

Herein a novel split-type photoelectrochemical (PEC) immunosensing platform was designed for sensitive detection of low-abundance biomarkers (prostate-specific antigen, PSA, used in this case) by coupling a peroxyoxalate chemiluminescence (PO-CL) self-illuminated system with digital multimeter (DMM) readout. The PEC detection device consisted of a capacitor/DMM-joined electronic circuit and a PO-CL-based self-illuminated cell. Initially, reduced graphene oxide-doped BiVO4 (BiVO4-rGO) photovoltaic materials with good photoelectric properties was integrated into the capacitor/DMM-joined circuit for photocurrent generation in the presence of hydrogen peroxide (H2O2, as the hole-trapping reagent).