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The need for an accurate and rapid diagnosis platform for highly contagious viruses, such as pandemic viruses, has rapidly increased. Conventional diagnostic methods in the initial stage of quarantine for the prevention of epidemic spread have encountered limitations such as a long operation time, occupation of a large space, and high cost per single operation. Here, a highly sensitive and selective portable diagnostic platform based on solid‐phase photonic polymerase chain reaction (SP‐PCR) is reported. The thermal cycle is operated by the photothermal energy converted from the photon energy of a light‐emitting diode (LED) through a gold layer to phonons. The formation of an amplicon, which is immobilized through N‐heterocyclic carbene, is confirmed through fluorescence on the surface of the miniaturized SP‐PCR chip. The practical applicability of the newly developed diagnosis platform for the recognition of the presence of a SARS‐CoV‐2‐specific genome sequence is demonstrated utilizing 100 clinical samples, including 72 COVID‐19‐positive clinical samples and 28 negative samples. [ABSTRACT FROM AUTHOR]

Fatal pathogenic organisms have been detected by various point‐of‐care tests (PoCTs) in clinical samples. PoCTs based on portable electrical devices are able to detect organisms in simple and rapid method. Although electrical PoCT devices show ultra sensitivity when detecting pathogens in standard samples, their industrialization has been limited due to low reproducibility, sensitivity, and specificity, resulting from nonspecific binding issues by media. In this research, a perpendicular N‐heterocyclic carbene self‐assembled monolayer (NHC‐SAM) conjugated on graphene micropattern field‐effect transistors (NGMFETs) is first demonstrated for monitoring pathogens. Two single bonds of NHCSAM on GM are investigated via density functional theory (DFT) and surface analyses. Bioreceptors are conjugated on the side gate‐modulated NGMFET for ultra‐stable on‐site detection. The side‐gated BNGMFETs system displayed remarkable performance in the detection of the following: i) SARS‐CoV‐2 spike protein S1 (limit of detection (LOD): ≈10 pg mL−1) in CTM, ii) O. tsutsugamushi Ab (LOD: ≈1 pg mL−1), and iii) E. coli (LOD: 10° CFU mL−1) in serum. Compared to commercial methodology, the platform presents 102 times higher LODs towards those pathogens in clinical samples with higher reproducibility. Based on these results, side‐gated BNGMFETs can be utilized as universal PoCT during pandemics. [ABSTRACT FROM AUTHOR]

Bitterness elicits unpleasant sensations in humans, which can hinder the acceptance of foods and medication adherence. Therefore, identifying and masking bitter tastes is crucial for developing palatable foods and promoting medication compliance in the food and pharmaceutical industries. To achieve this, employing agonism and antagonism of bitter taste receptors as effective strategies at the molecular level is essential. In this study, a bioelectronic tongue is developed to characterize the agonism and antagonism of bitter taste receptors. The human bitter taste receptors hTAS2R16 and hTAS2R31 are produced using an Escherichia coli expression system and reconstituted into nanodiscs (NDs). Subsequently, hTAS2R16‐ and hTAS2R31‐NDs are immobilized on the surface of graphene field‐effect transistors (FETs) to construct bioelectronic tongues. The developed system sensitively detected the bitter agonists, salicin and saccharin, at concentrations as low as 100 fM, with high selectivity in real‐time. The dose‐dependent curves shifted and K values decreased by the antagonists of hTAS2R16 and hTAS2R31, indicating antagonism‐based masking of bitter taste. Therefore, the developed bioelectronic tongue holds promise for identifying bitter tastes and evaluating the masking of bitterness based on the agonism and antagonism of hTAS2Rs. [ABSTRACT FROM AUTHOR]

A molecular diagnosis of the respiratory syncytial virus (RSV) without bulky and expensive instrumentation is of great importance for the early detection and prevention in a fast‐spreading pandemic. However, the current representative diagnostic methods have the limitation of being time‐consuming, cost, the processing time for polymerase chain reaction (PCR), and inaccurate for lateral flow assay (LFA), representatively. Herein, an integrated photonic digital PCR (dPCR) is developed with high‐velocity photonic scanner for in situ fluorescence detection by introducing the N‐heterocyclic carbene self‐assembled monolayer‐based Au film to prevent the quenching effect. The on‐site rapid molecular diagnostic platform shows the driving of 40 cycles in under 8 min and fluorescence scanning in under 7 min, resulting in a total analysis time within 15 min. In particular, the technology clearly demonstrates the classification of SARS‐CoV‐2 patients and healthy controls (99% in sensitivity, 98.6% in specificity, and 96.4% in accuracy with RdRp gene), comparing with standard RT‐qPCR. This platform can be utilized for prompt point‐of‐care molecular diagnostics in early diagnosis and large‐scale prevention of next pandemic spreading for upcoming infectious diseases and for the distinction diagnosis with other RSV. [ABSTRACT FROM AUTHOR]

Organic interfacial compounds (OICs) are required as linkers for the highly stable and efficient immobilization of bioprobes in nanobiosensors using 2D nanomaterials such as graphene. Herein, we first demonstrated the fabrication of a field‐effect transistor (FET) via a microelectromechanical system process after covalent functionalization on large‐scale graphene by introducing oligo(phenylene‐ethynylene)amine (OPE). OPE was compared to various OICs by density functional theory simulations and was confirmed to have a higher binding energy with graphene and a lower band gap than other OICs. OPE can improve the immobilization efficiency of a bioprobe by forming a self‐assembly monolayer via anion‐based reaction. Using this technology, Magainin I‐conjugated OGMFET (MOGMFET) showed a high sensitivity, high selectivity, with a limit of detection of 100 cfu mL−1. These results indicate that the OPE OIC can be applied for stable and comfortable interfacing technology for biosensor fabrication. [ABSTRACT FROM AUTHOR]

Quantum dots (QDs) can be integrated into a solid‐phase color converter (SCC) for white light‐emitting diodes (WLEDs). However, the development of QD‐based SCCs is prevented by the limitations of the QDs themselves, nonuniform dispersion or aggregation of the QDs, and heat accumulation by low thermal conductivity of the solid matrix. Herein, the development of new high‐quality CdZnSeS/ZnS QDs in a one spot synthesis is reported that have high photoluminescence quantum yield (up to 100% for green wavelengths), narrow emission spectra (full width at half maximum < 27.3 nm), and good color tunability in the green region, 496–586 nm. Seven different color QDs are used to fabricate liquid‐phase color converters (LCCs) for application in WLEDs with a remote configuration. The best LCC‐based WLEDs show not only intense bright day white light (correlated color temperature = 6029 K) with a maximum luminous efficacy of 222.7 lm W−1, but also excellent color quality (color rendering index = 95.1, as well as R9 = 94.4, and R13 = 97.1), which is very important in medical diagnostic lighting, dressing and display room lighting, painting and accent lighting. These results indicate remarkable progress both in the synthesis of high‐quality QDs and in the development of WLEDs for high‐performance commercial lighting devices. An optimized formulation of new liquid‐phase quantum dots for remote white light‐emitting diodes (WLEDs) is reported. The liquid‐phase color converter allows the WLED to produce intense bright day white light with excellent color quality. [ABSTRACT FROM AUTHOR]