ABSTRACT
Traumatic brain injury (TBI) is widely recognized as a global public health crisis, affecting millions of people each year, leading to permanent neurologic, emotional, and occupational disability, and highlighting the urgent need for rapid, sensitive, and early assessment. Here, we design a novel and simple lithography-free method for preparing dual-channel graphene-based field-effect transistors (G-FETs) and integrating them with microfluidic channels for simultaneously multiplexed detection of key blood TBI biomarkers: neurofilament light chain (NFL) and glial fibrillary acidic protein (GFAP). The G-FET utilizes an ingenious dual-channel electrode array design, where the source is shared between channels and the drains are independent of each other, which is the key to achieving simultaneous output of dual detection signals. At the same time, the microfluidic chip realizes microscale fluidic control and fast sample response time. This integrated detection system shows excellent sensitivity in biological fluids for the TBI biomarkers with detection limits as low as 55.63 fg/mL for NFL and 144.45 fg/mL for GFAP in phosphate-buffered saline (PBS) buffer, respectively. Finally, the clinical sample analysis shows promising performance for TBI detection, with an area under the curve (AUC) of 0.98 for the two biomarkers. And the combined dual-protein assay is also a good predictor of intracranial injury findings on computed tomography (CT) scans (AUC = 0.907). The integrated microfluidic G-FET device with a dual-signal output strategy has important potential for application in clinical practice, providing more comprehensive information for brain injury assessment.
Subject(s)
Biomarkers , Brain Injuries, Traumatic , Glial Fibrillary Acidic Protein , Brain Injuries, Traumatic/blood , Brain Injuries, Traumatic/diagnosis , Biomarkers/blood , Humans , Glial Fibrillary Acidic Protein/blood , Lab-On-A-Chip Devices , Neurofilament Proteins/blood , Neurofilament Proteins/analysis , Transistors, Electronic , Microfluidic Analytical Techniques/instrumentation , Microfluidic Analytical Techniques/methods , Graphite/chemistry , Limit of Detection , Biosensing Techniques/methods , Biosensing Techniques/instrumentationABSTRACT
Widespread distribution of porcine epidemic diarrhea virus (PEDV) has led to catastrophic losses to the global pig farming industry. As a result, there is an urgent need for rapid, sensitive and accurate tests for PEDV to enable timely and effective interventions. In the present study, we develop and validate a floating gate carbon nanotubes field-effect transistor (FG CNT-FET)-based portable immunosensor for rapid identification of PEDV in a sensitive and accurate manner. To improve the affinity, a unique PEDV spike protein-specific monoclonal antibody is prepared by purification, and subsequently modified on FG CNT-FET sensor to recognize PEDV. The developed FET biosensor enables highly sensitive detection (LoD: 8.1 fg/mL and 100.14 TCID50/mL for recombinant spike proteins and PEDV, respectively), as well as satisfactory specificity. Notably, an integrated portable platform consisting of a pluggable FG CNT-FET chip and a portable device can discriminate PEDV positive from negative samples and even identify PEDV and porcine deltacoronavirus within 1 min with 100% accuracy. The portable sensing platform offers the capability to quickly, sensitively and accurately identify PEDV, which further points to a possibility of point of care (POC) applications of large-scale surveillance in pig breeding facilities.
Subject(s)
Biosensing Techniques , Nanotubes, Carbon , Porcine epidemic diarrhea virus , Porcine epidemic diarrhea virus/isolation & purification , Animals , Swine , Biosensing Techniques/methods , Biosensing Techniques/instrumentation , Nanotubes, Carbon/chemistry , Limit of Detection , Immunoassay/methods , Immunoassay/instrumentation , Antibodies, Monoclonal/immunology , Transistors, Electronic , Swine Diseases/diagnosis , Swine Diseases/virology , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/analysis , Coronavirus Infections/diagnosis , Coronavirus Infections/veterinary , Coronavirus Infections/virology , Antibodies, Viral/immunology , Equipment DesignABSTRACT
BACKGROUND: Intestinal malrotation is an infrequent congenital anomaly primarily observed in neonates, and adult-onset cases are exceedingly rare. Studies on adult congenital intestinal malrotation are limited. METHODS: A case with congenital intestinal malrotation is reported in our study. The clinical data were collected and the treatment process and effect were evaluated. RESULTS: A 45-year-old female who had been experiencing vomiting for over 40 years was admitted to our hospital. According to the result of CT scan, intestinal volvulus accompanied by bowel obstruction was suspected. Then laparoscopic examination was applied to the patient and was ultimately diagnosed with adult congenital intestinal malrotation. We performed Ladd's procedure combined with gastrojejunostomy and Braun anastomosis. The patient recovered well and was successfully discharged from the hospital on the 13th day after surgery. After a 6-month follow-up, the symptom of vomiting was significantly alleviated and body weight was gained for 10 kg. She was very satisfied with the treatment. CONCLUSION: Adult congenital intestinal malrotation is a rare disease that is often misdiagnosed owing to nonspecific clinical manifestations. Therefore, awareness about this condition should be enhanced. Surgery remains the cornerstone of treatment for this disease. Combining gastrojejunostomy and Braun anastomosis with the traditional Ladd procedure can optimize surgical outcomes.
Subject(s)
Digestive System Abnormalities , Gastric Bypass , Intestinal Obstruction , Intestinal Volvulus , Infant, Newborn , Adult , Female , Humans , Middle Aged , Intestinal Volvulus/diagnosis , Intestinal Volvulus/surgery , Intestinal Volvulus/complications , Intestines/surgery , Intestinal Obstruction/surgery , Intestinal Obstruction/complications , Gastric Bypass/adverse effects , Vomiting/complicationsABSTRACT
Halide solid electrolytes, known for their high ionic conductivity at room temperature and good oxidative stability, face notable challenges in all-solid-state Li-ion batteries (ASSBs), especially with unstable cathode/solid electrolyte (SE) interface and increasing interfacial resistance during cycling. In this work, we have developed an Al3+-doped, cation-disordered epitaxial nanolayer on the LiCoO2 surface by reacting it with an artificially constructed AlPO4 nanoshell; this lithium-deficient layer featuring a rock-salt-like phase effectively suppresses oxidative decomposition of Li3InCl6 electrolyte and stabilizes the cathode/SE interface at 4.5â V. The ASSBs with the halide electrolyte Li3InCl6 and a high-loading LiCoO2 cathode demonstrated high discharge capacity and long cycling life from 3 to 4.5â V. Our findings emphasize the importance of specialized cathode surface modification in preventing SE degradation and achieving stable cycling of halide-based ASSBs at high voltages.
ABSTRACT
The point-of-care diagnosis of acute myocardial infarction (AMI), an extremely lethal disease with only a few hours of golden rescue time, is significant and urgently required. Here, we describe a plug-and-play carbon nanotube field effect transistor (CNT-FET) bio-chip supported with a smart portable readout for ultrasensitive and on-site testing of cardiac troponin I (cTnI), which is one of the most specific and valuable biomarkers of AMI. A modified clustered regularly interspaced short palindromic repeats (CRISPR)/Cas12a system, featuring the G-triplex structured reporter, was first combined with the CNT-FET to realize non-nucleic acid detection. Such a unique CNT-FET biosensor achieved the high sensitivity (LOD: 0.33 fg/mL), which is expected to give timely warning in the early stage of myocardial injury. In addition, a bilayer gate dielectric consisting of Y2O3/HfO2, employed into the passivation process, enabled the high environmental stability and repeatability of CNT-FET. More importantly, the homemade compact chip readout forged a field-deployable cTnI analytical tool, realizing "plasma-to-answer" performance for AMI patients in point-of-care testing scenarios. The developed technology holds promise to help doctors make clinical decisions faster, especially in remote areas.
Subject(s)
Biosensing Techniques , Myocardial Infarction , Humans , Point-of-Care Systems , CRISPR-Cas Systems/genetics , Troponin I , Myocardial Infarction/diagnosis , Myocardial Infarction/geneticsABSTRACT
Osteoarthritis is a degenerative disease characterized by abnormal neurovascularization at the osteochondral junctions, the regulatory mechanisms of which remain poorly understood. In the present study, a murine osteoarthritic model with augmented neurovascularization at the osteochondral junction is used to examine this under-evaluated facet of degenerative joint dysfunction. Increased extracellular RNA (exRNA) content is identified in neurovascularized osteoarthritic joints. It is found that the amount of exRNA is positively correlated with the extent of neurovascularization and the expression of vascular endothelial growth factor (VEGF). In vitro binding assay and molecular docking demonstrate that synthetic RNAs bind to VEGF via electrostatic interactions. The RNA-VEGF complex promotes the migration and function of endothelial progenitor cells and trigeminal ganglion cells. The use of VEGF and VEGFR2 inhibitors significantly inhibits the amplification of the RNA-VEGF complex. Disruption of the RNA-VEGF complex by RNase and polyethyleneimine reduces its in vitro activities, as well as prevents excessive neurovascularization and osteochondral deterioration in vivo. The results of the present study suggest that exRNAs may be potential targets for regulating nerve and blood vessel ingrowth under physiological and pathological joint conditions.
Subject(s)
Osteoarthritis , Vascular Endothelial Growth Factor A , Mice , Animals , Vascular Endothelial Growth Factor A/metabolism , Molecular Docking Simulation , Osteoarthritis/metabolism , RNA/geneticsABSTRACT
Local pH of the brain microenvironment is a prominent indicator for assessing health status and is closely related to many diseases; therefore, the development of effective in vivo pH methods is of great importance. This work demonstrates a dual-needle biosensor based on a solution-gate field-effect transistor (FET) for selective and sensitive monitoring of pH in cerebrospinal fluid in the central nervous system. The sensor consists of two parts: a needle FET modified with high-purity carbon nanotubes for electrical signal conduction and a needle gate modified with polyaniline for specific pH response. Based on the device's specific shape and sensing characteristics, the dual-needle sensor is sensitive to the measurement of pH in the living brain while maintaining excellent stability. The prepared dual-needle biosensor exhibits a high Nernstian response of 53.7 mV/pH over a wide pH range from 4.0 to 9.0 and excellent selectivity toward pH against other potential interfering species in the brain. Either in the case of directly injecting weak acids and bases into the rat brain or in the constructed acute acid-base poisoning model, the dual-needle biosensor can respond sensitively to the pH changes of the rat brain. This work has produced a unique dual-needle FET biosensor with high reliability and stability, which provides a new method for real-time monitoring of dynamic pH changes in the body.
Subject(s)
Biosensing Techniques , Nanotubes, Carbon , Rats , Animals , Reproducibility of Results , Biosensing Techniques/methods , Needles , Hydrogen-Ion ConcentrationABSTRACT
Chondroitin sulfate (CS) is an important extracellular matrix component of mineralized tissues. It participates in biomineralization, osteoblast differentiation and promotes bone tissue repair in vitro. However, the mechanism in which CS functions is unclear. Accordingly, an in-depth investigation of how CS participates in mineralization was conducted in the present study. Chondroitin sulfate was found to directly induce intrafibrillar mineralization of the collagen matrix. The mineralization outcome was dependent on whether CS remained free in the extracellular matrix or bound to core proteins; mineralization only occurred when CS existed in a free state. The efficacy of mineralization appeared to increase with ascending CS concentration. This discovery spurred the authors to identify the cause of heterotopic ossification in the Achilles tendon. Chondroitin sulfate appeared to be a therapeutic target for the management of diseases associated with heterotopic calcification. A broader perspective was presented on the applications of CS in tissue engineering.
Subject(s)
Biomineralization , Chondroitin Sulfates , Chondroitin Sulfates/pharmacology , Bone and Bones/metabolism , Collagen/metabolism , Extracellular Matrix/metabolismABSTRACT
The external acid environment of cancer cells is different from that of normal cells, making a profound impact on cancer progression. Here we report a simple poly-l-lysine-modified graphene field-effect transistor (PLL@G-FET) for in situ monitoring of extracellular acidosis around cancer cells. PLL is a well-known material with good biocompatibility and is rich in amino groups that are sensitive to hydrogen ions. After a simple drop-casting of PLL on the reduced graphene oxide (RGO) FET surface, the PLL@G-FET was able to realize the real-time monitoring of the localized pH change of cancer cells after the cancer cells were grown on the device. The PLL@G-FET sensor achieved a Nernstian value of 52.9 mV/pH in phosphate buffer saline from pH 4.0 to 8.0. In addition, the sensor exhibited excellent biocompatibility as well as good anti-interference ability in the cell culture medium. Furthermore, the device was used to real-time monitor the extracellular pH changes of MCF-7 cells under the intervention of different concentrations of drugs. This developed pH-sensitive FET provides a new method to study the extracellular acid environment in situ and helps us to enhance our understanding of cancer cell metabolism.
Subject(s)
Biosensing Techniques , Graphite , Neoplasms , Humans , Transistors, Electronic , Biosensing Techniques/methods , Graphite/toxicity , MCF-7 Cells , Hydrogen-Ion ConcentrationABSTRACT
Chemical communication via neurotransmitters is central to brain functions. Nevertheless, in vivo real-time monitoring of neurotransmitters released in the brain, especially the electrochemically inactive molecules, remains a great challenge. In this work, a novel needle field-effect transistor (FET) microsensor based on an acupuncture needle is proposed, which is demonstrated to be capable of real-time monitoring dopamine molecules as well as neuropeptide Y in vivo. The FET microstructure is fabricated by successively wrapping an insulating layer and a gold layer on the top of the needle, where the needle and the Au served as the source and drain, respectively. After assembling reduced graphene oxide (RGO) between the source and drain electrodes, the specific aptamer is immobilized on the RGO, making this needle-FET biosensor highly selective and sensitive to real-time monitor neurotransmitters released from rat brain, even in a Parkinson's diseases model. Furthermore, the needle-FET biosensor is applied to detect a variety of targets including hormones, proteins, and nucleic acid. By constructing a FET sensing interface on an acupuncture needle and implanting the sensor in a rat's brain for in vivo detection, this work provides a new sight in the FET domain and further expands the species of real-time in vivo detection.
Subject(s)
Acupuncture Therapy , Biosensing Techniques , Graphite , Rats , Animals , Graphite/chemistry , Gold/chemistry , Neurotransmitter Agents , Transistors, ElectronicABSTRACT
The detection of human body temperature is one of the important indicators to reflect the physical condition. In order to accurately judge the state of the human body, a high-performance temperature sensor with fast response, high sensitivity, and good linearity characteristics is urgently needed. In this paper, the positive temperature characteristics of graphene-polydimethylsiloxane (PDMS) composite with high sensitivity were studied. Besides, doping polyaniline (PANI) with special negative temperature characteristics as the temperature compensation of the composite finally creatively solved the problem of sensor nonlinearity from the material level. Thus, the PANI:graphene and PDMS hybrid temperature sensor with extraordinary linearity and high sensitivity is realized by establishing the space-gap model and mathematical theoretical analysis. The prepared sensor exhibits high sensitivity (1.60%/°C), linearity (R2 = 0.99), accuracy (0.3 °C), and time response (0.7 s) in the temperature sensing range of 25-40 °C. Based on this, the fabricated temperature sensor can combine with the read-out circuit and filter circuit with a high-precision analog digital converter (ADC) to monitor real-time skin temperature, ambient temperature, and respiratory rate, et al. This high-performance temperature sensor reveals its great potential in electronic skin, disease diagnosis, medical monitoring, and other fields.
Subject(s)
Graphite , Humans , Temperature , Aniline Compounds , DimethylpolysiloxanesABSTRACT
Proteoglycans consist of core proteins and one or more covalently-linked glycosaminoglycan chains. They are structurally complex and heterogeneous. Proteoglycans bind to cell surface receptors, cytokines, growth factors and have strong affinity for collagen fibrils. Together with their complex spatial structures and different charge densities, proteoglycans are directly or indirectly involved in biomineralization. The present review focused on the potential mechanisms of proteoglycans-mediated biomineralization. Topics covered include the ability of proteoglycans to influence the proliferation and differentiation of odontoblasts and osteoblasts through complex signaling pathways, as well as regulate the aggregation of collagen fibrils and mineral deposition. The functions of proteoglycans in mineralization regulation and biomimetic properties render them important components in bone tissue engineering. Hence, the integrated impact of proteoglycans on bone formation was also succinctly deliberated. The potential of proteoglycans to function therapeutic targets for relieving the symptoms of ectopic mineralization and mineralization defects was also comprehensively addressed.
Subject(s)
Biomineralization , Proteoglycans , Collagen/metabolism , Extracellular Matrix/metabolism , Glycosaminoglycans/metabolism , Proteoglycans/chemistryABSTRACT
Two-dimensional (2D) halide perovskite material is characterized by a mixed conducting behavior that possesses both electronic and ionic conductivity. The study on the influence of the light on ion migration in the 2D perovskite is helpful to improve the performance of perovskite-based optoelectronic devices. Here, we constructed an exfoliated 2D perovskite/carbon nanotubes (CNTs) heterostructure optical synapse, in which CNTs can be used as nanoprobes to qualitatively observe the ion aggregation or dissipation process in 2D perovskite, and found that light significantly changes the memory curve of the reconfigurable optical synapses. Through the molecular dynamic simulation, the dynamic process of ion migration in the heterostructure was simulated and the electrostatic interaction effect of nonequilibrium charge distribution of CNTs on iodide ion was demonstrated. Finally, an effective light-controlled process was realized through the synapses, which in situ regulated the performance of the weight-value discretized BP (WD-BP) neural network. This work lays a foundation for the future development of intelligent nano-optoelectronic devices.
ABSTRACT
Bioelectronics, an emerging discipline formed by the biology and electronic information disciplines, has maintained a state of rapid development since its birth. Amongst the various functional bioelectronics materials, bacteriorhodopsin (bR), with its directional proton pump function and favorable structural stability properties, has drawn wide attention. The main contents of the paper are as follows: Inspired by the capacitive properties of natural protoplast cell membranes, a new bio-capacitor based on bR and artificial nanochannels was constructed. As a point of innovation, microfluidic chips were integrated into our device as an ion transport channel, which made the bio-capacitor more stable. Meanwhile, a single nanopore structure was integrated to improve the accuracy of the device structure. Experiments observed that the size of the nanopore affected the ion transmission rate. Consequently, by making the single nanopore's size change, the photocurrent duration time (PDT) of bR was effectively regulated. By using this specific phenomenon, the original transient photocurrent was successfully transformed into a square-like wave.
ABSTRACT
Developing soft electrothermal actuators (ETAs) has drawn extensive concern in recent years. This article presents a comprehensive review on recent progress of soft ETAs through five sections: device design on structure and materials, property, fabrication methods, applications, and prospects. It's found that the fabrication process can be divided into standard surface complementary metal oxide semiconductor technology, novel laser scribing, and inkjet printing method. Moreover, current applications involve three aspects: mechanical applications, optical applications, and biomimetic applications. It will develop in the direction of increasing electrothermal efficiency and response speed emphatically. This review encourages achievement of its higher performance and broad applications in the future.
Subject(s)
Robotics , Biomimetics , Lasers , Printing, Three-DimensionalABSTRACT
OBJECTIVE: To evaluate the effectiveness and safety of microsurgical gonadal-inferior epigastric vein anastomosis for the treatment of the nutcracker phenomenon (NCP) associated with left gonadal vein varices with reflux. METHODS: Thirty-five patients with NCP associated with left gonadal vein varices with reflux diagnosed in our hospital from June 2016 to June 2018 were included. All patients underwent a shunt operation consisting of microsurgical gonadal-inferior epigastric vein anastomosis, and the patients were followed up for 1 year. RESULTS: All patients were successfully operated on, with an average operation time of 96.5 ± 12.3 min. After a 1-year follow-up, the symptom of gross hematuria disappeared in 3 patients (including 1 woman). For the other 32 patients, the sperm concentration (27.43 ± 8.68 × 106/ml) and motility (33.06 ± 4.27%) postoperatively were significantly higher than that preoperatively (16.21 ± 6.43 × 106/ml and 23.48 ± 4.43%, respectively) (P < 0.05); among these patients, 2 had natural pregnancies with their spouses. The peak velocity (PV) at the aortomesenteric portion of the left renal vein (LRV) and the PV ratio between the aortomesenteric and hilar portion of the LRV significantly decreased after surgery (117.9 ± 30.4 cm/s vs 76.6 ± 18.5 cm/s; 7.3 ± 0.7 vs 4.1 ± 0.4). Two patients had complications of mild hydroceles requiring no intervention, and no major complications were observed during and after surgery. CONCLUSION: Our results suggest that the microsurgical gonadal-inferior epigastric vein anastomosis is both effective and safe to treat patients with gonadal varicose veins caused by the nutcracker phenomenon.
Subject(s)
Renal Nutcracker Syndrome/surgery , Testis/blood supply , Varicose Veins/surgery , Adult , Anastomosis, Surgical/methods , Female , Hematuria/etiology , Humans , Iliac Vein/surgery , Male , Microsurgery , Regional Blood Flow , Renal Nutcracker Syndrome/complications , Treatment Outcome , Varicose Veins/complications , Varicose Veins/physiopathology , Vascular Surgical Procedures/methods , Young AdultABSTRACT
Single-crystal (SC) perovskite is currently a promising material due to its high quantum efficiency and long diffusion length. However, the reported perovskite photodetection range (<800 nm) and response time (>10 µs) are still limited. Here, to promote the development of perovskite-integrated optoelectronic devices, this work demonstrates wider photodetection range and shorter response time perovskite photodetector by integrating the SC CH3NH3PbBr3 (MAPbBr3) perovskite on silicon (Si). The Si/MAPbBr3 heterojunction photodetector with an improved interface exhibits high-speed, broad-spectrum, and long-term stability performances. To the best of our knowledge, the measured detectable spectrum (405-1064 nm) largely expands the widest response range reported in previous perovskite-based photodetectors. In addition, the rise time is as fast as 520 ns, which is comparable to that of commercial germanium photodetectors. Moreover, the Si/MAPbBr3 device can maintain excellent photocurrent performance for up to 3 months. Furthermore, typical gray scale face imaging is realized by scanning the Si/MAPbBr3 single-pixel photodetector. This work using an ultrafast photodetector by directly integrating perovskite on Si can promote advances in next-generation integrated optoelectronic technology.
ABSTRACT
Two-dimensional (2D) hybrid perovskite sandwiched between two long-chain organic layers is an emerging class of low-cost semiconductor materials with unique optical properties and improved moisture stability. Unlike conventional semiconductors, ion migration in perovskite is a unique phenomenon possibly responsible for long carrier lifetime, current-voltage hysteresis, and low-frequency giant dielectric response. While there are many studies of ion migration in bulk hybrid perovskite, not much is known for its 2D counterparts, especially for ion migration induced by light excitation. Here, we construct an exfoliated 2D perovskite/carbon nanotube (CNT) heterostructure field effect transistor (FET), not only to demonstrate its potential in photomemory applications, but also to study the light induced ion migration mechanisms. We show that the FET I-V characteristic curve can be regulated by light and shows two opposite trends under different CNT oxygen doping conditions. Our temperature-dependent study indicates that the change in the I-V curve is probably caused by ion redistribution in the 2D hybrid perovskite. The first principle calculation shows the reduction of the migration barrier of I vacancy under light excitation. The device simulation shows that the increase of 2D hybrid perovskite dielectric constant (enabled by the increased ion migration) can change the I-V curve in the trends observed experimentally. Finally, the so synthesized FET shows the multilevel photomemory function. Our work shows that not only we could understand the unique ion migration behavior in 2D hybrid perovskite, it might also be used for many future memory function related applications not realizable in traditional semiconductors.
ABSTRACT
MXenes have attracted great attention for their potential applications in electrochemical and electronic devices due to their excellent characteristics. Traditional sound sources based on the thermoacoustic effect demonstrated that a conductor needs to have an extremely low heat capacity and high thermal conductivity. Hence, a thin MXene film with a low heat capacity per unit area (HCPUA) and special layered structure is emerging as a promising candidate to build loudspeakers. However, the use of MXenes in a sound source device has not been explored. Herein, we have successfully prepared sound source devices on an anodic aluminum oxide (AAO) and a flexible polyimide (PI) substrates by using the prepared Ti3C2 MXene nanoflakes. Due to the larger interlayer distance of MXene, the MXene-based sound source device has a higher sound pressure level (SPL) than that of graphene of the same thickness. High-quality Ti3C2 MXene nanoflakes were fabricated by selectively etching the Ti3AlC2 powder. The as-fabricated MXene sound source device on an AAO substrate exhibits a higher SPL of 68.2 dB (f = 15 kHz) and has a very stable sound spectrum output with frequency varying from 100 Hz to 20 kHz. A theoretical model has been built to explain the mechanism of the sound source device on an AAO substrate, matching well with the experimental results. Furthermore, the MXene sound source device based on a flexible PI substrate has been attached to the arms, back of the hand, and fingers, indicating an excellent acoustic wearability. Then, the MXene film is packaged successfully into a commercial earphone case and shows an excellent performance at high frequencies, which is very suitable for human audio equipment.
ABSTRACT
Exosomes are small membrane-bound nanovesicles with a size of 50-150 nm which contain many functional biomolecules, such as nucleic acids and proteins. Due to their high homology with parental generation, they are of great significance in clinical diagnosis. At present, the quantitative detection of low concentrations of cancer-derived exosomes present in biofluids is still a great challenge. In this study, we develop an electrical and label-free method to directly detect exosomes with high sensitivity based on a reduced graphene oxide (RGO) field effect transistor (FET) biosensor. An RGO FET biosensor modified with specific antibody CD63 in the sensing area was fabricated and was used for electrical and label-free quantification of exosomes. The method achieved a low limit of detection down to 33 particles/µL, which is lower than that of many other available methods. In addition, the FET biosensor was employed to detect exosomes in clinical serum samples, showing significant differences in detecting healthy people and prostate cancer (PCa) patients. Different from other technologies, this study provides a unique technology capable of directly quantifying exosomes without labeling, indicating its potential as a tool for early diagnosis of cancer.