Signal Magnification Research Articles

Photoelectrochemical platform for glucose sensing based on g-C3N4/ZnIn2S4 composites coupled with bi-enzyme cascade catalytic in-situ precipitation

A unique bi-enzyme photoelectrochemical (PEC) biosensor is developed for selective and sensitive detection of glucose based on bi-enzyme cascade catalytic in-situ precipitation for signal amplification. In this design, the composites of ZnIn2S4 and graphitic carbon nitride (g-C3N4/ZnIn2S4) with better photoelectrochemical properties are used as the photoactive material. Subsequently, horseradish peroxidase (HRP) and glucose oxidase (GOx) are anchored on the modified electrode surface. In the presence of 4-chloro-1-naphthol (4-CN) and glucose, GOx catalyzes the oxidation of glucose to produce H2O2, which oxidizes 4-CN to generate a precipitate in the presence of HRP. The precipitate on the electrode surface can dramatically reduce the photocurrent signal. In the light of the signal magnification process, the bi-enzyme biosensor presents a “signal-off” sensing mode for glucose detection, which displays a dynamic detection range of 1–10000 μM with a low limit of detection of 0.28 μM. Furthermore, the constructed PEC bi-enzyme biosensor exhibits a tremendous potential for quantitative detection of glucose in practical applications.

A bombykol electrochemical receptor sensor and its kinetics

This study aimed to explore the interaction between bombykol and BmOR1 and also provide a paradigm for agroforestry pest control. The electrochemical biosensor signal amplification system was used: nanogold with horseradish peroxidase. An electrochemical bilayer nanogold membrane receptor sensor was developed using the following schemes and processes: twice self-assembly of nanogold and succeeding absorption of Bombyx mori olfactory receptor 1 (BmOR1); sex pheromone–binding protein; spectral scanning and transmission electron microscope to characterize nanogold sol; and atomic force microscope, cyclic voltammetry, and AC impedance methods to characterize individual processes of sensor assembly. The amperometric I–T curve was adopted to measure the response current upon interaction with different concentrations of bombykol (diluted in phosphate-buffered saline) and BmOR1. The results demonstrated the receptor–ligand interaction pattern, which was similar to enzymatic reaction kinetics, with the activation constant Ka of up to 8.57 × 10−20 mol/L and signal magnification of about 10,000-fold. In this study, the simulation of intracellular receptor signaling cascade by an electrochemical signal amplification system helped in directly measuring BmOR1–bombykol ligand interaction and exploring the kinetics after the self-assembly of BmOR1 on the biosensor. It provided a novel platform for future studies on receptor–ligand interaction.

Rapid and Ultrasensitive Quantification of Multiplex Respiratory Tract Infection Pathogen via Lateral Flow Microarray based on SERS Nanotags

Respiratory tract infections (RTIs) are severe acute infectious diseases, which require the timely and accurate identification of the pathogens involved so that the individual treatment plan can be selected, including optimized use of antibiotics. However, high throughput and ultrasensitive quantification of multiple nucleic acids is a challenge in a point of care testing (POCT) device.Methods: Herein, we developed a 2×3 microarray on a lateral flow strip with surface enhanced Raman scattering (SERS) nanotags encoding the nucleic acids of 11 common RTI pathogens. On account of the signal magnification of encoded SERS nanotags in addition to the high surface area to volume ratio of the nitrocellulose (NC) membrane, rapid quantification of the 11 pathogens with a broad linear dynamic range (LDR) and ultra-high sensitivity was achieved on one lateral flow microarray.Results: The limit of detection (LOD) for influenza A, parainfluenza 1, parainfluenza 3, respiratory syncytial virus, coxiella burnetii, legionella pneumophila, influenza B, parainfluenza 2, adenovirus, chlamydophila pneumoniae, and mycoplasma pneumoniae were calculated to be 0.031 pM, 0.030 pM, 0.038 pM, 0.038 pM, 0.040 pM, 0.039 pM, 0.035 pM, 0.032 pM, 0.040 pM, 0.039 pM, and 0.041 pM, respectively. The LDR of measurement of the target nucleic acids of the eleven RTI pathogens were 1 pM-50 nM, which span 5 orders of magnitude.Conclusions: We anticipate this novel approach could be widely adopted in the early and precise diagnosis of RTI and other diseases.

No Low-frequency Emission from Extremely Bright Fast Radio Bursts

Abstract We present the results of a coordinated campaign conducted with the Murchison Widefield Array (MWA) to shadow fast radio bursts (FRBs) detected by the Australian Square Kilometre Array Pathfinder (ASKAP) at 1.4 GHz, which resulted in simultaneous MWA observations of seven ASKAP FRBs. We de-dispersed the 24 × 1.28 MHz MWA images across the 170–200 MHz band taken at 0.5 s time resolution at the known dispersion measures (DMs) and arrival times of the bursts and searched both within the ASKAP error regions (typically ∼10′ × 10′), and beyond (4° × 4°). We identified no candidates exceeding a 5σ threshold at these DMs in the dynamic spectra. These limits are inconsistent with the mean fluence scaling of α = −1.8 ± 0.3 ( , where ν is the observing frequency) that is reported for ASKAP events, most notably for the three high-fluence ( Jy ms) FRBs 171020, 180110, and 180324. Our limits show that pulse broadening alone cannot explain our non-detections, and that there must be a spectral turnover at frequencies above 200 MHz. We discuss and constrain parameters of three remaining plausible spectral break mechanisms: free–free absorption, intrinsic spectral turnover of the radiative processes, and magnification of signals at ASKAP frequencies by caustics or scintillation. If free–free absorption were the cause of the spectral turnover, we constrain the thickness of the absorbing medium in terms of the electron temperature, T, to <0.03 (T/104 K)−1.35 pc for FRB 171020.

Tetrathiafulvalene (TTF)-Annulated Calix[4]pyrroles: Chemically Switchable Systems with Encodable Allosteric Recognition and Logic Gate Functions

Molecular and supramolecular systems capable of switching between two or more states as the result of an applied chemical stimulus are attracting ever-increasing attention. They have seen wide application in the development of functional materials including, but not limited to, molecular and supramolecular switches, chemosensors, electronics, optoelectronics, and logic gates. A wide range of chemical stimuli have been used to control the switching within bi- and multiple state systems made up from either singular molecular entities or supramolecular ensembles. In general, chemically triggered switching systems contain at least two major functional components that provide for molecular recognition and signal transduction, respectively. These components can be connected to one another via either covalent or noncovalent linkages. Of particular interest are switchable systems displaying cooperative or allosteric features. Such advanced control over function is ubiquitous in nature and, in the case of synthetic systems, may allow the capture and release of a targeted chemical entity or permit the transduction of binding information from one recognition site to another. Allosterically controlled complexation and decomplexation could also permit the amplification or deamplification of analyte-specific binding affinity, lead to nonlinear binding characteristics, or permit a magnification of output signals. Our own efforts to develop chemically driven supramolecular switches, advanced logic gates, and multifunction cascade systems have focused on the use of tetrathiafulvalene (TTF) annulated calix[4]pyrroles (C4Ps). These systems, TTF-C4Ps, combine several orthogonal binding motifs within what are conformationally switchable receptor frameworks. Their basic structure and host-guest recognition functions can be controlled via application of an appropriate chemical stimulus. Homotropic or heterotropic allosteric molecular recognition behavior is often seen. This has allowed us to (1) produce self-assembled structures, (2) control switching between bi- and multistate constructs, (3) generate chemical logic gates performing chemical-based Boolean logic operations, (4) create ionically controlled three-state logic systems that release different chemical messengers and activate disparate downstream reactions, and (5) encode a variety advanced functional operations into what are relatively simple molecular-scale devices. Looking to the future, we believe that exploiting allosteric control will expand opportunities for supramolecular chemists and allow some of the complexity seen in biology to be reproduced in simple constructs. Of particular appeal would be a capacity to release chemical messengers at will, perhaps after a prior capture and chemical modification step, that then encode for further downstream functions as seen in the case of the small molecules, such as neurotransmitters and pheromones, used by nature for the purpose of intraentity communication. Molecular scale logic devices with allosteric functions are thus the potential vanguard of a new area of study involving interactions between multiple discrete components with an emphasis on functional outcomes.

Real-time Fourier transformation based on the bandwidth magnification of RF signals.

We demonstrate a novel real-time Fourier transformation scheme with megahertz-level resolution realized by bandwidth magnification of radio frequency (RF) signals. Before the frequency-to-time mapping, the RF signal is modulated on an optical frequency comb, and then extracted by a Vernier comb filter. As a result, RF components can be separated in the spectrum with a greatly magnified optical bandwidth. Thus, even with limited dispersion provided by an ordinary optical fiber, the frequency-dependent pulses can be distinguished in the time domain. Experimentally, the RF signal with the frequency difference of 60MHz is separated by around 123ps in the time domain, equivalent to the dispersion of 1975.5ps/GHz (2.47×105 ps/nm), while the physical dispersion is 1500ps/nm. Thus, based on the bandwidth magnification of signals, the dispersion is equivalently amplified by 165 times.

Classification of the emotional stress and physical stress using signal magnification and canonical correlation analysis

In affective computing, stress recognition mainly focuses on the relation of stress and photoelectric information. Researchers have used artificial intelligence to determine stress and computer identification channels. However, in applications such as health and security, Emotional stress (ES) information is usually to be alongside physical stress (PS) information, making it urgent to classify ES and PS. The thermal signals of ES and PS have yet to be classified, for which, signal amplification is offered. In this study, we propose a classification algorithm based on signal amplification and correlation analysis called Eulerian magnification-canonical correlation analysis. This signal amplification algorithm expands the signals of ES and PS in different frequency domains. Sparse coding and canonical correlation analysis then fuse the original signal and its amplified features. The extracted entropy features are used to train the correlation weight between ES and PS, which formulates stress classifications. The new classification method achieves an accuracy rate of 90%. This study can lead to a practical system for the noninvasive assessment of stress states for health or security applications.

New Insights toward Efficient Charge-Separation Mechanism for High-Performance Photoelectrochemical Aptasensing: Enhanced Charge-Carrier Lifetime via Coupling Ultrathin MoS2 Nanoplates with Nitrogen-Doped Graphene Quantum Dots.

Deeply understanding the internal mechanism of the photoelectrohemical (PEC) process is conducive to fabricate high-performance PEC biosensors. In this work, we proposed a new insight toward an efficient charge-separation mechanism in high-performance PEC biosensors. Specifically, we disclosed that the lifetimes of photogenerated charge carriers of ultrathin MoS2 nanosheets could be prolonged by approximately millisecond time scales after a proper mole ratio of NGQDs were coupled, leading to the promoted charge separation and a giant photocurrent signal magnification. Benefiting from the dramatic signal amplification and the introduction of acetamiprid aptamer, subfemtomolar level detection of acetamiprid is achieved, which makes our strategy among the most sensitive electronic approaches for PEC-based monitoring of targets. This study was beneficial to further understand the charge-separation mechanism in PEC biosensing, which paved the way for the development of more efficient PEC biosensors.

Novel Fluorescence Signal Magnified Chemosensors for Detection of Fe3+ and Hg2+ Ions

AbstractTwo novel chemosensors were designed and synthesized, which could detect Fe3+ and Hg2+ with high sensitivity. By controlling the molecular ratio of hydrazine hydrate to BODIPY derivatives (OB2), these two different sensors were obtained. The one contains two BODIPY units in each molecule (OS21), the other contains one BODIPY unit in each molecule (OS11). The structures of OS21 and OS11 were studied by 1H‐NMR, Fourier transform infrared spectra (FTIR), and mass spectrometry (MS). The measurements show that OS11 was stable in pH range of 3.65‐11.09, while OS21 was stable in pH range of 3.16‐11.88. Upon the addition of Fe3+ and Hg2+ ions, fluorescence of OS11 and OS21 was quenched notably. Besides, OS21 was more sensitive to both Fe3+ and Hg2+ than OS11. And the color of OS11 and OS21 were also changed dramatically with the contacting of Fe3+ and Hg2+. Job's plot indicated that the molar binding ratio of OS11 to Fe3+ was 1:2, to Hg2+ was 1:1. The molar binding ratio of OS21 to Fe3+ was 1:3, to Hg2+ was 1:1. Also, it is found that the sensor could detect Fe3+ and Hg2+ in 0.5 μM concentration. Furthermore, the OS21 shows a fluorescence signal magnification effect as expected comparing with OS11. Moreover, the binding sites in the sensors for Fe3+ and Hg2+ ions were investigated as well.

A signal amplification electrochemical aptasensor for the detection of breast cancer cell via free-running DNA walker

Herein, a signal magnification electrochemical aptasensor for the detection of breast cancer cell via free-running DNA walker is constructed. Theoretically, just one DNA walker, released by target cell-responsive reaction, can automatically cleave all D-RNA (a chimeric DNA/RNA oligonucleotide with a cleavage point rArU) anchored on electrode into shorter produces, giving rise to considerably detectable signal finally. Under the optimal conditions, the electrochemical signal decreased linearly with the concentration of MCF-7 cell. The linear range is from 0 to 500 cells mL−1 with a detection limit of 47 cellsmL−1. In a word, this approach may have advantages over traditional reported DNA machines for bioassay, particularly in terms of ease of operation, cost efficiency, free of labeling and of complex track design, which may hold great potential for wide application.

Paper-Based Analytical Devices Relying on Visible-Light-Enhanced Glucose/Air Biofuel Cells.

A strategy that combines visible-light-enhanced biofuel cells (BFCs) and electrochemical immunosensor into paper-based analytical devices was proposed for sensitive detection of the carbohydrate antigen 15-3 (CA15-3). The gold nanoparticle modified paper electrode with large surface area and good conductibility was applied as an effective matrix for primary antibodies. The glucose dehydrogenase (GDH) modified gold-silver bimetallic nanoparticles were used as bioanodic biocatalyst and signal magnification label. Poly(terthiophene) (pTTh), a photoresponsive conducting polymer, served as catalyst in cathode for the reduction of oxygen upon illumination by visible light. In the bioanode, electrons were generated through the oxidation of glucose catalyzed by GDH. The amount of electrons is determined by the amount of GDH, which finally depended on the amount of CA15-3. In the cathode, electrons from the bioanode could combine with the generated holes in the HOMO energy level of cathode catalysts pTTh. Meanwhile, the high energy level photoexcited electrons were generated in the LUMO energy level and involved in the oxygen reduction reaction, finally resulting in an increasing current and a decreasing overpotential. According to the current signal, simple and efficient detection of CA15-3 was achieved.

A reusable optical biosensor for the ultrasensitive and selective detection of unamplified human genomic DNA with gold nanostars.

A Surface Plasmon Resonance imaging (SPRi) based DNA sensors for the selective and ultrasensitive human genomic DNA detection, directly extracted from lymphocytes (bypassing PCR amplification), is reported. To achieve DNA detection, a rationally chosen star-shaped nanoparticle (NP), namely gold nanostar (AuNS), has been applied, for the first time, in a sandwich-like assay based on the selective capturing of specific DNA targets and the subsequent signal amplification by a secondary DNA probe linked to AuNS. The plasmonic profile, size and electric field enhancements at the star tips contributed to the maximization of plasmon coupling between LSPs and SPs as aimed for analytical signal magnification. The system was first tested using short synthetic DNA target sequences and applied to DNA biosensing, lowering 610-fold the detection limit from 6.1 nM (without NSs labeling) to 10 pM (with NSs labeling). Then the biosensor was applied to genomic DNA samples, extracted from human lymphocytes and undergoing only to a simple ultrasonic fragmentation, lowering (~435 fold) the detection limit from 3.0 fM (without NSs labeling) to 6.9 aM (with NSs labeling). Thanks to the assay optimization, we proved that tuning the NSs surface coverage with DNA linked to nanoparticles is crucial not only for the increase of signals but also for the regenerability/reusability of the biosensor for tens of measurement cycles.

Implementation of the photonic time-stretch concept using an incoherent pulsed light source.

We propose a new technique to realize photonic time stretching of radio-frequency (RF) signals by using a time-gated (pulsed) incoherent-light source. The proposed system provides similar performance specifications (stretch factor, temporal aperture, and resolution) to those of a conventional coherent system but using a temporal gating process that is significantly longer than the transform-limited pulse duration of the equivalent coherent configuration. We experimentally demonstrate temporal magnification and compression of high-speed RF signals, with time-stretch factors ranging from 0.65 to 8.66, using a broadband (11.6nm) incoherent-light source temporally gated over ∼163 ps. In one of the reported experiments, we achieve a resolution of ∼67.5 ps over a temporal aperture of ∼23 ns, representing a time-bandwidth product of >340.

High precision micro-impulse measurements for micro-thrusters based on torsional pendulum and sympathetic resonance techniques

A sympathetic resonance theory is analyzed and applied in a newly developed torsional pendulum to measure the micro-impulse produced by a μN s-class ablative pulsed plasma thruster. According to theoretical analysis on the dynamical behaviors of a torsional pendulum, the resonance amplification effect of micro-signals is presented. In addition, a new micro-impulse measurement method based on sympathetic resonance theory is proposed as an improvement of the original single pulse measurement method. In contrast with the single pulse measurement method, the advantages of sympathetic resonance method are significant. First, because of the magnification of vibration signals due to resonance processes, measurement precision for the sympathetic resonance method becomes higher especially in reducing reading error. With an increase in peak number, the relative errors induced by readout of voltage signals decrease to approximately ±1.9% for the sympathetic resonance mode, whereas the relative error in single pulse mode is estimated as ±13.4%. Besides, by using the resonance amplification effect the sympathetic resonance method makes it possible to measure an extremely low-impulse beyond the resolution of a thrust stand without redesigning or purchasing a new one. Moreover, because of the simple operational principle and structure the sympathetic resonance method is much more convenient and inexpensive to be implemented than other high-precision methods. Finally, the sympathetic resonance measurement method can also be applied in other thrust stands to improve further the ability to measure the low-impulse bits.

Quantification of Iron in Seawater at the Low Picomolar Range Based on Optimization of Bromate/Ammonia/Dihydroxynaphtalene System by Catalytic Adsorptive Cathodic Stripping Voltammetry

A new analytical protocol for the challenging analysis of total dissolved iron at the low picomolar level in oceanic waters suitable for onboard analysis is presented. The method is based on the revision of the adsorptive properties of the iron/2,3-dihydroxynaphthalene (Fe/DHN) complexes on the hanging mercury drop electrode with catalytic enhancement by bromate ions. Although it was based on a previously proposed reagent combination, we show here that the addition of an acidification/alkalinization step is essential in order to cancel any organic complexation, and that an extra increment of the pH to 8.6-8.8 leads to the definition of a preconcentration-free procedure with the lowest detection limit described up to now. For total dissolved iron analysis, samples were acidified to pH 2.0 in the presence of 30 μM DHN and left to equilibrate overnight. A 10 mL sample was subsequently buffered to a pH of ∼8.7 in the presence of 20 mM bromate: a 60 s deposition at 0 V led to a sensitivity of 34 nA nM(-1) min(-1), a 4-fold improvement over previous methods, that translated in a limit of detection of 5 pM (2-20 fold improvement). Several tests proved that a nonreversible reaction in the time scale of the analysis, triggered by the acidification/alkalinization step, was behind the signal magnification. The new method was validated onboard via the analysis of reference material and via intercalibration against flow injection analysis-chemiluminescence on Southern Ocean surface samples.

Study on Enzyme Linked Immunosorbent Assay Using Paper-based Micro-zone Plates

Photolithography was used to pattern hydrophobic design on common quantitative filter paper,based on which we successfully fabricated the paper-based micro-zone plates.In order to improve its protein-absorbing capability for further signal magnification,modified silicon dioxide(SiO2) micro-beads were deposited onto the surface of paper.Then indirect-ELISA for goat anti-rabbit IgG was applied on the 36-well plates.Taking enzyme linked goat anti-rabbit IgG as an example,loading SiO2 beads could remarkably increase the quantity of the absorbed protein by 20%-700%.When this method was used for goat anti-rabbit IgG detection,signals were magnified by 20%-150%,and the linear range of detection was from 3×10-12 mmol/zone to 3×10-8 mmol/zone under given conditions.In this manner,bio-reagent consumption was reduced to 3-5 μL per zone,test time dropped to 25min per plate and the cost of fabrication reduced to $1.1 per plate,which indicated a promising application foreground for new disease diagnosis devices.

Study on Enzyme Linked Immunosorbent Assay Using Paper-based Micro-zone Plates

Abstract Photolithography was used to pattern hydrophobic design on common quantitative filter paper, and then the paper-based micro-zone plates were successfully fabricated. In order to improve its protein-adsorbing capacity for further signal magnification, modified silicon dioxide (SiO2) micro-beads were deposited onto the surface of paper. Indirect-ELISA for goat anti-rabbit IgG was realized on the 36-zone plates. Taking enzyme-linked goat anti-rabbit IgG as an example, loading SiO2 beads could remarkably increase the quantity of the adsorbed protein by 20%–700%. When this method was used for goat anti-rabbit IgG detection, signals were magnified by 20%–150%, and the linear range of detection was from 3 × 10−12 mmol to 3 × 10−8 mmol per zone. In this manner, bio-reagent consumption was reduced to 3–5 μL per zone, test time dropped to 25 min per plate and the cost of fabrication was reduced to $1.1 per plate. This work suggests a new way for development of new diagnosis devices.

Changes in a nanoparticle’s spectroscopic signal mediated by the local environment

Using a first-principles theoretical model the adsorption of a methyl radical on different sized silver nanoparticles is compared to the adsorption of the same radical on model surfaces. Calculations of our structural, dynamical and electronic properties indicated that small changes in the local environment will lead to small changes in infrared (IR) wavenumbers, but in dramatic changes in the IR signal. Our calculations indicate the lower the adsorption site coordination, the higher is the signal strength, suggesting that small changes in the electronic charge distribution will result in bigger changes in the polarizability and hence in the spectroscopic signal intensity. This effect explains, among others, the signal magnification observed for nanoparticles in surface enhanced Raman spectroscopic (SERS) experiments.

Study on APD real time compensation methods of laser Detection system

With the monochromatic and the directional capability of the laser, laser detection system is confidential in anti-jamming. Detection accuracy is improved significantly as the result of laser's good orientation ability. Sensitivity is enhanced as laser's high-brightness characteristic. With the development of laser technology and laser devices, laser detections are developed both in civilian and military areas. In the military field, laser detection system has been widely applied in various types of tactical missiles, the technique is more mature.Because photo detectors receive the backscattering echo signal of target in laser detection system, they are required sensitive enough to weak signal. With APD's salient features of high sensitivity, rapid response speed, high response frequency and low noise equivalent power, etc.; PIN is replaced by APD to improve sensitivity of laser detection system in recent years. The signal magnification is inadequate in laser detection system, the detector output is usually amplified by multistage amplifiers. And then the system noise includes detector noise and latter amplifiers noise. With its high internal gain, APD becomes the primary noise source of receiving system. This point can be attested by analyzing the transfer function of laser detection system receiver. To ensure the system detecting ability, APD noise must be mitigated as low as possible. According to a large number of experiments, the power signal-to-noise (SNR) and the best multiplication factor of APD are mostly affected by background radiation and temperature. In order to make APD operate at state of the best multiplication factor, the optimum bias must be selected due to the actual operating circumstance. Therefore, APD realtime compensation must be adopted.The existing APD compensation includes the constant false alarm rate compensation, the noise compensation and the temperature compensation. The features of these compensations are obtained by analyzing their operating principles. The constant false alarm rate compensation can't detect the pulse signal which comes randomly. Therefore real-time performance can't be realized. The noise compensation can meet the request of real-time performance. If it is used in the environment where background light is intense or changes acutely, there is a better effect. The temperature compensation can also achieve the real-time performance request. If it is used in the environment where temperature changes acutely, there is also a better effect. Aim at such problems, this paper presents that different APD real-time compensations should be adopt to adapt to different environments. The exiting temperature compensation adjusts output voltage by using variable resistance to regulate input voltage. Its structure is complex; the real-time performance is worse. In order to remedy these defects, a real-time temperature compensation which is based on switch on-off time of switching power supply is designed. Its feasibility and operating stability are confirmed by plate making and experiment.At last, the comparison experiments between the real-time noise compensation and the real-time temperature compensation is carried out in the environments where temperature is almost invariant and background light acutely changes from5lux to150lux . The result shows that the operating effect of the real-time noise compensation is better here, the noise minifies to a sixth of original noise. The comparison experiments between the real-time noise compensation and the real-time temperature compensation is carried out in darkroom where background light is 5lux and temperature almost rapidly changes from −20°C to 80°C. The result shows that the operating effect of the real-time temperature compensation is better here, the noise minifies to a seventh of original noise. Moreover, these methods can be applied to other type detection systems of weak photoelectric signal; they have high actual application value.

High Performance Phototransistors of a Planar Conjugated Copolymer

A planar conjugated copolymer named HXS-1 was applied in thin film phototransistors. Similar to organic field-effect transistors using V(G) to control the source-drain current, in phototransistors, the light is used to substitute V(G) as an independent variable to control the output of the transistors to realize light detection and signal magnification in a single organic device. All devices exhibited high performance with an on/off ratio up to 4.6 × 10(4) (the highest on/off ratio of organic or polymer phototransistors), which could be assigned to i) the wide absorption features of HXS-1 in the whole UV-vis range, ii) the ideal HOMO energy level of HXS-1 (5.21 eV) to align with Au electrodes (5.2 eV) and iii) the high mobility of the polymer thin films (∼0.06 cm(2) /Vs). Moreover, the devices, both under continuous operation conditions and long term measurement conditions, exhibited excellent stability, indicating potential applications of the devices in polymer-based optoelectronics.