Signal-amplified surface-enhanced Raman scattering using core/shell satellite nanoparticles for norovirus detection.

The development of an innovative approach is explored to amplify the signal of a surface-enhanced Raman scattering (SERS)-based detection system using a novel nanotag: Au@Ag NPs covered by satellite AuNPs and conjugated by 4-mercaptbenzoic acid (4-MBA) as a Raman tag (Au@Ag-MBA-AuNPs). The Au@Ag-MBA-AuNPs nanotags showed strong SERS activities with an enhancement factor in the 10 order of magnitude. This indicates the formation of many hot spots due to the combination of core-shell nanoparticles and satellite AuNPs on the surface of Au@Ag-MBA NPs.

Point-of-care dengue detection: polydopamine-modified electrode for rapid NS1 protein testing for clinical samples.

Early diagnosis of dengue infection by detecting the dengue virus non-structural protein 1 (DENV-NS1) is important to the patients to initiate speedy treatment. Enzyme-linked immunosorbent assay (ELISA)-based NS1 detection and RT-PCR are time-consuming and too complex to be employed in remote areas of dengue-endemic countries. Meanwhile, those of NS1 rapid test by lateral flow assay suffer from low detection limit.

Development of disposable electrode for the detection of mosquito-borne viruses.

Development of disposable, rapid, and convenient biosensor with high sensitivity and reliability is the most desired method of viral disease prevention. To achieve this goal, in this work, a practical impedimetric biosensor has been implemented into a disposable electrode on a screen-printed carbon electrode (SPCE) for the detection of two mosquito-borne viruses. The biosensor fabrication has step-wisely carried out on the disposable electrode surface at room temperature: starting from conductive film formation, physical binding of the gold nanoparticles (AuNPs)-polyaniline (PAni) into the conductive film, and biofunctionalization.

Nanosphere Structures Using Various Materials: A Strategy for Signal Amplification for Virus Sensing.

Nanomaterials have been explored in the sensing research field in the last decades. Mainly, 3D nanomaterials have played a vital role in advancing biomedical applications, and less attention was given to their application in the field of biosensors for pathogenic virus detection. The versatility and tunability of a wide range of nanomaterials contributed to the development of a rapid, portable biosensor platform.

CdSe-CoO@TiO nanoflower-based photoelectrochemical platform probing visible light-driven virus detection.

The design and construction of a visible light-driven photoelectrochemical (PEC) device is described based on a CdSe-CoO@TiO nanoflower (NF). Moreover, an application to the ultrasensitive detection of viruses, such as hepatitis E virus (HEV), HEV-like particles (HEV-LPs), and SARS-CoV-2 spike protein in complicated lysate solution, is demonstrated. The photocurrent response output of a PEC device based on CdSe-CoO@TiO is enhanced compared with the individual components, TiO and CdSe-CoO.

Improvement of Modular Protein Display Efficiency in SpyTag-Implemented Norovirus-like Particles.

Genetic fusion and chemical conjugation are the most common approaches for displaying a foreign protein on the surface of virus-like particles (VLPs); however, these methods may negatively affect the formation and stability of VLPs. Here, we aimed to develop a modular display platform for protein decoration on norovirus-like particles (NoV-LPs) by combining the NoV-LP scaffold with the SpyTag/SpyCatcher bioconjugation system, as the NoV-LP is an attractive protein nanoparticle to carry foreign proteins for various applications. The SpyTagged-NoV-LPs were prepared by introducing SpyTag peptide into the C-terminus of the norovirus VP1 protein.

Pt-embodiment ZIF-67-derived nanocage as enhanced immunoassay for infectious virus detection.

A facile and general strategy has been employed to develop highly-active nanozyme for immunoassay purposes. The hollow nanostructure of the CoO nanocages (NCs) was anchoring the platinum nanoparticles (PtNPs) enclosed by the exposed oxides framework nd formed PtNPs@CoO NCs. The embodiment of PtNPs was considered an ideal hybrid nanozyme that efficiently catalyzed the oxidation of the substrate molecules with enhanced activity.

Advancement of dengue virus NS1 protein detection by 3D-nanoassembly complex gold nanoparticles utilizing competitive sandwich aptamer on disposable electrode.

Signal amplification have been centralized in developing the highly reliable biosensor for analyte detection with a narrow detection window. We proposed an aptasensor to provide a highly sensitive early-stage diagnostic platform of dengue virus NS1 protein (DENV-NS1) by dual-approach - colorimetric and electrochemical detection. This work utilized two different aptamers specific to DENV-NS1: One conjugated to gold nanoparticles (AuNPs), forming AuNPs-Apt and its complementary sequence aptamer, forming AuNPs-Apt.

Self-Assembled Chromogenic Polymeric Nanoparticle-Laden Nanocarrier as a Signal Carrier for Derivative Binary Responsive Virus Detection.

In the current biosensor, the signal generation is limited to single virus detection in the reaction chamber. An adaptive strategy is required to enable the recognition of multiple viruses for diagnostics and surveillance. In this work, a nanocarrier is deployed to bring specific signal amplification into the biosensor, depending on the target viruses.

Molybdenum Trioxide Quantum Dot-Encapsulated Nanogels for Virus Detection by Surface-Enhanced Raman Scattering on a 2D Substrate.

The use of nanogels (NGs) to modulate surface-enhanced Raman scattering (SERS) activities is introduced as an innovative strategy to address certain critical issues with SERS-based immunoassays. This includes the chemical deformation of SERS nanotags, as well as their nonspecific interactions and effective "hotspots" formation. Herein, the polymeric cocoon and stimuli-responsive properties of NGs were used to encapsulate SERS nanotags containing plasmonic molybdenum trioxide quantum dots (MoO-QDs).

Plasmon Nanocomposite-Enhanced Optical and Electrochemical Signals for Sensitive Virus Detection.

The social impact of virus spread is immeasurable. Vaccine prophylaxes take considerable time to develop because clinical trials are required. The best initial response to an emerging virus is establishing a virus detection technology adapted by simply preparing virus-specific antibodies.

Self-assembled chromogen-loaded polymeric cocoon for respiratory virus detection.

Inspired by the self-assembly approach, in this work, the chromogen, 3,3',5,5'-tetramethylbenzidine (TMB), was successfully co-precipitated in aqueous solution to form collective nanoparticles (NPs) of signal molecules (TMB-NPs). Utilizing poly(lactide-co-glycolide) (PLGA) in the molecular delivery approach, the formed emulsion nanovesicle (TMB-NPs@PLGA) exhibits an enrichment of the collective signal molecules in a single antibody-antigen conjugation. A specific antibody-conjugated TMB-NPs@PLGA forms an immunocomplex sandwich structure upon the addition of influenza virus (IV)/A.

Hollow magnetic-fluorescent nanoparticles for dual-modality virus detection.

Combination of magnetic nanomaterials with multifunctionality is an emerging class of materials that exhibit tremendous potential in advanced applications. Synthesizing such novel nanocomposites without compromising magnetic behavior and introducing added functional properties is proven challenging. In this study, an optically active quantum dot (QD) (core) encapsulated inside iron oxide (hollow shell) is prepared as the first electrochemical/fluorescence dual-modality probe.

Ultrasensitive Detection of the Hepatitis E Virus by Electrocatalytic Water Oxidation Using Pt-CoO Hollow Cages.

A sensitive virus detection method applicable for an early stage increases the probability of survival. Here, we develop a simple and rapid detection strategy for the detection of the hepatitis E virus (HEV) by an electrocatalytic water oxidation reaction (WOR) using a platinum (Pt)-incorporated cobalt (Co)-based zeolite imidazole framework (ZIF-67). The surface cavity of ZIF-67 enables the rich loading of Pt NPs, and subsequent calcination etches the cavity, promoting the electrocatalytic activity of Pt-CoO HCs.

Plasmonic/magnetic molybdenum trioxide and graphitic carbon nitride quantum dots-based fluoroimmunosensing system for influenza virus.

A novel magnetic/plasmonic-assisted fluoro-immunoassay system is developed for the detection of influenza virus using magnetic-derivatized plasmonic molybdenum trioxide quantum dots (MP-MoO QDs) as the plasmonic/magnetic agent and fluorescent graphitic carbon nitride quantum dots (gCNQDs) as the monitoring probe. Specific antibody against influenza A virus was conjugated onto the surface of MP-MoO QDs and gCNQDs, respectively. In the presence of influenza A virus (as the test virus), a core-satellite immunocomplex is formed between the antibody-conjugated nanomaterials (Ab-MP-MoO QDs and Ab-gCNQDs) and their interaction resulted in the modulation and gradual enhancement of the fluorescence intensity of the detection probe with the influenza virus concentration-dependent increase.

Advancement of capture immunoassay for real-time monitoring of hepatitis E virus-infected monkey.

Rapid increasing outbreak of Hepatitis E virus (HEV) shows an urgent need of HEV detection. Instead of time consuming and expensive RT-qPCR, an efficient and quick monitoring system is in utmost demand which can be comparable with the RT-qPCR in term of reliability and detection limit. An advanced platform for immunoassay has been constructed in this study by a nanozyme that constitutes anti-HEV IgG antibody-conjugated gold nanoparticles (Ab-AuNPs) as core and in situ silver deposition on the surface of Ab-AuNPs as outer shell.

Dual modality sensor using liposome-based signal amplification technique for ultrasensitive norovirus detection.

Sensitive and accurate detection methods for infectious viruses are the pressing need for effective disease diagnosis and treatment. Herein, based on VO nanoparticles-encapsulated liposomes (VONP-LPs) we demonstrate a dual-modality sensing platform for ultrasensitive detection of the virus. The sensing performance relies on intrinsic peroxidase and electrochemical redox property of VO nanoparticles (VO NPs).

Enhanced colorimetric detection of norovirus using in-situ growth of Ag shell on Au NPs.

Norovirus (NoV) is a leading cause of acute gastroenteritis. The low infectious dose and environmental stability of NoV facilitate its effective transmission through a variety of modes such as food, water and person-to-person. The available enzyme-linked immunosorbent assay (ELISA) for NoV detection has low sensitivity due to the low catalytic activity of the peroxidase used, and thus, a reliable ultrasensitive bioassay is needed.

Femtomolar Detection of Dengue Virus DNA with Serotype Identification Ability.

Dengue surveillance trusts only on reverse transcription-polymerase chain reaction (RT-PCR) type methodologies for confirmation of dengue virus serotypes; however, its real time application is restricted due to the expensive, complicated, and time-consuming process. In search of a new sensing system, here, we have reported a two-way-detection method for Dengue virus (DENV) serotype identification along with DNA quantification by using a new class of nanocomposite of gold nanoparticles (AuNP) and nitrogen, sulfur codoped graphene quantum dots (N,S-GQDs). The N,S-GQDs@AuNP has been used for serotype detection via a simple fluorescence technique using four dye-combined probe DNAs which is further validated by confocal microscopy.