Sensor Letters
·
2016
·Vol. 14
·期 4
·369-375
·
IF 0
Youwang Hu,Chengzhi Xu,Ji'an Duan,Jiwen Xiang,Shu Wang,Xiaoyan Sun
Surface Acoustic Wave (SAW) sensors have received great attention because of their compact design and excellent sensing performance, including high sensitivity, low detection limits. However, SAW sensors generally suffer from low quality of the solid thin films which has a significant
effect to the detection performance of the sensors. To solve this problem, three different methods (spin coating, drop coating and spray coating) for fabricating thin films have been investigated for gaseous nitrogen dioxide (NO2) SAW sensors in this work. Spray coating method showed
its advantages in improving the solid film quality of the sensing layer and the performance of the sensors. SEM characterization shows that the spray coating films are more uniform and poly-porous. Sensors with spray coating film can detect NO2 range from sub ppm to hundreds ppm
with high sensibility and stability. Its sensitivity is 42.31 Hz/ppm and its sensing limit is down to 57.2 ppb.
研究领域:
材料科学
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环境监测
·
传感器技术
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DOI
Microsystems & Nanoengineering
·
2024
·Vol. 10
·期 1
·1-14
·
IF 7.3
Qin Xianming,Liu Xianglian,Liu Shuo,Zhang Chuanyu,Bai Ningning,Li Xue,Wang Weidong,Liu Dan,Yang Qiqi,Yang Ruiguo,Shen Yajing,Wei Xueyong
Surface acoustic wave (SAW) tweezers are a promising multifunctional micromanipulation method that controls microscale targets via patterned acoustic fields. Owing to their device structure and bonding process, most SAW tweezers have limitations in terms of controlling the position and motion of the acoustic traps, as they generate an acoustic field with a fixed region and adjust the manipulation effects via signal modulation. To address this challenge, we propose movable SAW tweezers with a multilayer structure, achieving dynamic control of their wave field and acoustic trap positions; we demonstrate their precise manipulation functions, such as translation, in-plane rotation, out-of-plane rotation, and cluster formation, on a wide spectrum of samples, including particles, bubbles, droplets, cells, and microorganisms. Our method not only improves the degree of freedom and working range of SAW tweezers but also allows for precise and selective manipulation of microtargets via microtools and localized wavefields. Owing to their flexibility, versatility, and biocompatibility, the movable SAW tweezers can be a practical platform for achieving arbitrary manipulation of microscale targets and have the potential to play significant roles in biomedical microrobotics.
研究领域:
生物医学工程
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微纳米技术
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细胞生物学
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DOI
PubMed
高影响因子
LAB ON A CHIP
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2025
·
IF 5.4
Chunhua He,Huasheng Zhuo,Canfeng Yang,Jianxin Wang,Xian Jiang,Fan Li,Chengxu Lin,Hai Yang,Tuying Yong,Xiangliang Yang,Zhiyong Liu,Yan Ma,Lei Nie,Guanglan Liao,Tielin Shi
Target particle encapsulation is crucial in droplet microfluidics for high-throughput applications like single-cell sequencing and drug screening. However, it faces limitations, with encapsulation rates of only 10% to 30% due to suspension density and the inherent functionality of the chip being restricted by the Poisson distribution. This leads to reagent waste and reduced effectiveness in applications requiring ultra-high multiplexing or extensive particle analysis, due to the massive empty droplets. Here we propose a droplet microfluidic system integrating surface acoustic wave (SAW) and sheath flow control. Suspensions of varying concentrations within the channel are initially pre-focused by sheath fluid, and then acoustically focused into a linear arrangement by SAW. Spacing between particles can be regulated by modulating the sheath fluid, ensuring sequential encapsulation of cells or beads in individual droplets. Thermal shock generated by the SAW, particle and droplet frequency, and particle encapsulation ratio are all elaborately evaluated. The results demonstrate that our system reaches an exciting single-bead packing efficiency of up to 78%, and achieves a packing rate of more than 60% for both high and low concentrations of solutions for polystyrene microspheres, magnetic beads and H22 cells, 6 times higher than the theoretical upper limit of the conventional method and 1.8 times higher than the Poisson distribution. More importantly, our system is designed to be free of structural and parametric constraints, which is quite important in future practical application. Thus, our on-chip particle focusing control method and droplet microfluidic system provide great potential in biological applications needing a high single-particle encapsulation ratio in limited partitions, such as ultra-high multiplex digital biomolecular detection, single-cell analysis, drug screening, and single exosome detection.
研究领域:
生物技术
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医学工程
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分子生物学
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DOI
PubMed
高影响因子
ACS Sensors
·
2020
·
IF 7.333
Chenyun Wang,Cancan Wang,Dan Jin,Yi Yu,Fan Yang,Yulin Zhang,Qunfeng Yao,Guo-Jun Zhang
In this study, we report a gold nanoparticle (AuNP)-amplified surface acoustic wave (SAW) sensor for exosome detection with high sensitivity. The SAW chip was self-assembled with mercapto acetic acid to generate carboxylic groups via the Au–S bond. Anti-CD63 was then anchored onto the chip by pretreatment with 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) and N-hydroxysuccinimide,1-hydroxypyrrolidine-2,5-dione (NHS). Due to the existence of a membrane protein, CD63, on the exosome surface, exosomes could be bound onto the antibody-immobilized SAW chip. To amplify the detection signal, both the biotin-conjugated epithelial cell adhesion molecule (EpCAM) antibody as a secondary antibody and AuNP-labeled streptavidin were applied onto the exosome-bound SAW chip, resulting in AuNP assembly on the chip through biotin–avidin recognition. The sensor was capable of detecting 1.1 × 103 particles/mL exosomes, which was about 2 orders of magnitude higher than those detected by the strategy without using signal amplification. The sensor also achieved a satisfactory specificity and could detect the low-abundance exosomes directly in blood samples from cancer patients with minimal disturbance. This makes the SAW sensor useful for early diagnosis of cancer.
研究领域:
生物医学工程
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纳米技术
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癌症诊断
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DOI
PubMed
高影响因子
ACS Applied Electronic Materials
·
2023
·
IF 4.7
Jie Yang,Tianran Wang,Chushu Zhu,Xuyuan Yin,Peitao Dong,Xuezhong Wu
The surface acoustic wave (SAW) technology has been widely used for hazardous gas detection, but the low sensitivity, poor selectivity, long response/recovery time, and signal “false positives” of the sensors have limited its application for gas-phase explosives detection. In this paper, a composite gas-phase explosives sensor with frequency-resistance dual-signal display was designed by transferring 25 layers of graphene (rGO) in the sensing area of the SAW device and coupling p-aminothiophenol (PATP)-modified gold nanoparticles (AuNPs). The rGO:AuNP/PATP-SAW sensor shows signal response from two signal dimensions, frequency and resistance, to 0.1–80 ppm TNT gas with a low detection limit (DL) of 41.2 ppb. The composite sensor has a short response/recovery time (9.8 s/27.1 s) with good selectivity, repeatability, and stability. The excellent gas-sensitive performance of the rGO:AuNP/PATP-SAW sensor was attributed to the fact that PATP provides a large number of selective capture groups, which are enriched in the sensing area by the presence of multiple strong interactions with 2,4,6-trinitrotoluene (TNT) molecules. This work will provide scientific guidance for the engineering promotion of surface acoustic wave gas-phase explosives sensors.
研究领域:
材料科学
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传感技术
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爆炸物检测
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产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2025
·
IF 7.7
Shengyu Wen,Long Li,Jian Zhou,Jinbo Zhang,Hui Chen,Yihao Guo,Yongqing Fu,Huigao Duan
Dimethyl methylphosphonate (DMMP) is commonly used as a simulant for sarin in calibrating organophosphorus detectors. Among various DMMP sensors, surface acoustic wave (SAW) sensors are gaining significant attention for their attributes of wireless monitoring, digital outputs, and cost-effectiveness. However, there is a significant challenge remained as it is difficult to simultaneously improve sensitivity and reduce limit of detection (LOD) when monitoring the DMMP at room temperature. In this study, a comprehensive strategy was developed by applying Cu ion-doped ZrO 2 (Cu-ZrO 2 ) nanocomposite as a high-performance sensitive layer coated onto an ultrahigh frequency (4.98 GHz) SAW sensor for detecting low concentration DMMP at room temperature under ultraviolet (UV) light activation. The developed ultrahigh frequency SAW DMMP sensor demonstrated an exceptional sensitivity of 1198.2 kHz/ppm, ∼1198 times higher than that of a conventional SAW sensor operated at a frequency of 162.4 MHz. It showed an ultralow LOD of 10 ppb, rapid response/recovery times of 39 s/25 s, and a long-term stability up to 30 days. Such the exceptional performance is primarily attributed to the Cu-ZrO 2 sensitive layer, of which the doped Cu ions lead to the formation of more unsaturated Zr 4 + ions, increasing the Lewis acid sites and promoting the effective interactions between Lewis sites and DMMP molecules. In addition, attributed to the ultrahigh resonant frequency of the SAW device, a giant elastic loading effect was identified to significantly enhance the sensing performance. This study provides a promising and versatile methodology for achieving ultrahigh sensitivity DMMP detection based on the SAW technology.
研究领域:
材料科学
·
传感技术
·
环境监测
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产品关联
DOI
高影响因子
ACS Sensors
·
2020
·
IF 7.333
Xi Chen,Meng Wang,Gang Zhao
Monitoring of the hemostasis status is essential for therapeutic anticoagulants, undergoing surgery, cardiovascular diseases, etc. Although the clinical values of conventional blood coagulation tests have been well demonstrated, these devices have limitations such as large and expensive equipment, excessive sample volumes, long turnaround times, and difficulty in miniaturization for point-of-care use. Here, we present a novel strategy to evaluate blood hemostasis using the single-port Love-mode surface acoustic wave (SLSAW) sensor. The SLSAW sensor was designed as a plug-and-play-type unit for disposable use and operated under the harmonic resonant mode to produce frequency response to the blood coagulation cascade. Compared with a quartz crystal microbalance, Lamb wave, and film bulk acoustic resonator, the frequency shift of SLSAW was significantly increased, ranging from approximately 8960 to 10 368 kHz, which indicated enhancement of the signal-to-noise ratio. To demonstrate the feasibility of the SLSAW, studies were carried out to examine the effects of temperature and clotting reagents on coagulation times and kinetics. Activated partial thromboplastin times of plasma were validated by comparing with SYSMEX CA-7000 with the correlation (R2) as 0.996. In terms of coagulation kinetics, reaction time, clot formation time, maximum frequency shift, and clot formation rate of whole blood correlated well with corresponding parameters of the standard thromboelastography (TEG) analyzer (R2 = 0.9942, 0.9868, 0.9712, and 0.9939, respectively). The SLSAW sensor, with the advantages of low cost, small size, little sample consumption (1 μL), disposable use, and simple operation, is a promising tool for point-of-care diagnosis of hemostasis.
研究领域:
医学工程
·
生物医学
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DOI
高影响因子
LAB ON A CHIP
·
2025
·
IF 5.4
Tao Zhou,Ran Tao,Yan Yu,Chong Li,Zhang Haonan,Jing-Ting Luo,Chen Fu,Fujian Ren,Yong Qing Fu
Chiral organic-inorganic hybrid perovskite films hold significant promise for optoelectronic applications due to their unique optical activity and excellent optoelectronic properties. However, their air and moisture sensitivity necessitates inert atmosphere processing, hindering practical application. In this work, we present a closed acoustofluidic system utilizing surface acoustic wave-based microcentrifugation for the synthesis of high-quality synthesizing (S-MBA)2PbI4 films. By confining both synthesis and film deposition within a sealed chamber, this approach eliminates air exposure, enabling the fabrication of films with enhanced crystallinity and a reduced bandgap of 2.37 eV. The resulting chiral perovskite films exhibit significant circular dichroism, with an asymmetry factor of 9.3×10-4. Furthermore, control over film surface roughness (achieving < 0.6 μm) is demonstrated through modulation of acoustic operation parameters. The cost-effectiveness and versatility of this acoustic microcentrifugation system highlight its potential for advanced film material fabrication.
研究领域:
材料科学
·
光学工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2019
·
IF 7.65
J.L. Wang,Y.J. Guo,G.D. Long,Y.L. Tang,Q.B. Tang,X.T. Zu,J.Y. Ma,B. Du,H. Torun,Y.Q. Fu
Surface acoustic wave (SAW)-based formaldehyde gas sensor using bi-layer nanofilms of bacterial cellulose (BC) and polyethyleneimine (PEI) was developed on an ST-cut quartz substrate using sol-gel and spin coating processes. BC nanofilms significantly improve the sensitivity of PEI films to formaldehyde gas, and reduces response and recovery times. The BC films have superfine filamentary and fibrous network structures, which provide a large number of attachment sites for the PEI particles. Measurement results obtained using in situ diffuse reflectance Fourier transform infrared spectroscopy showed that the primary amino groups of PEI strongly adsorb formaldehyde molecules through nucleophilic reactions, thus resulting in a negative frequency shift of the SAW sensor due to the mass loading effect. In addition, experimental results showed that the frequency shifts of the SAW devices are determined by thickness of PEI film, concentration of formaldehyde and relative humidity. The PEI/BC sensor coated with three layers of PEI as the sensing layer showed the optimal sensing performance, which had a frequency shift of 35.6 kHz for 10 ppm formaldehyde gas, measured at room temperature and 30 % RH. The sensor also showed good selectivity and stability, with a low limit of detection down to 100 ppb.
研究领域:
材料科学
·
环境监测
·
生物医学工程
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产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2023
·
IF 8.4
Wei Wu,Jingyu Long,Yuanjun Guo,Xiaotao Zu,Sean Li,Xia Xiang
A surface acoustic wave (SAW) H 2 S gas sensor based on CuO-TiO 2 p-n heterojunction film was designed and fabricated. The sensor exhibits high sensitivity to H 2 S due to the significant current response of CuO-TiO 2 film to H 2 S gas and the appropriate work point of SAW sensor based on CuO-TiO 2 composite film. The linearity change for sensor frequency shift is strongly associated with the location of work point when the H 2 S concentration increases from 1 to 300 ppm. In addition, the porosity of CuO-TiO 2 film is beneficial to the efficient adsorption for H 2 S, leading to the higher frequency shift of the sensor. The SAW sensor also shows good selectivity and stability to H 2 S with stable frequency shift under different humidity levels.
研究领域:
材料科学
·
传感器技术
·
气体检测
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产品关联
DOI
高影响因子
Nanomaterials
·
2023
·Vol. 14
·期 1
·89
·
IF 5.3
Xuming Wang,Xin Li,Qiang Wu,Yubin Yuan,Weihua Liu,Chuanyu Han,Xiaoli Wang
The increasing threat of nerve agents has prompted the need for gas sensors with fast response, high sensitivity, and good stability. In this work, the hexafluoroisopropanol functional group was modified on a porous aromatic framework material, which served as a sensitive material for detecting dimethyl methylphosphonate. A nerve agent sensor was made by coating sensitive materials on a surface acoustic wave device. Lots of pores in sensitive materials effectively increase the specific surface area and provide channels for diffusion of gas molecules. The introduction of hexafluoroisopropanols enables the sensor to specifically adsorb dimethyl methylphosphonate and improves the selectivity of the sensor. As a result, the developed gas sensor was able to detect dimethyl methylphosphonate at 0.8 ppm with response/recovery times of 29.8/43.8 s, and the detection limit of the gas sensor is about 0.11 ppm. The effects of temperature and humidity on the sensor were studied. The results show that the baseline of the sensor has a linear relationship with temperature and humidity, and the temperature and humidity have a significant effect on the response of the sensor. Furthermore, a device for real-time detection of nerve agent is reported. This work provides a new strategy for developing a gas sensor for detecting nerve agents.Keywords:surface acoustic wave;hexafluoroisopropanol;gas sensor;dimethyl methylphosphonate
研究领域:
化学传感器
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材料科学
·
分析化学
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产品关联
DOI
PubMed
高影响因子
Nanomaterials
·
2023
·Vol. 13
·期 21
·2871
·
IF 5.3
Xuming Wang,Xin Li,Qiang Wu,Yubin Yuan,Weihua Liu,Chuanyu Han,Xiaoli Wang
In recent years, the increasing severity of chemical warfare agent threats to public safety has led to a growing demand for gas sensors capable of detecting these compounds. However, gas sensors used for the detection of chemical warfare agents must overcome limitations in sensitivity, selectivity, and reaction speed. This paper presents a sensitive material and a surface acoustic gas sensor for detecting dimethyl methyl phosphonate. The results demonstrate that the sensor exhibits good selectivity and could detect 80 ppb of dimethyl methyl phosphonate within 1 min. As an integral component of the sensor, the microstructure and adsorption mechanism of silica molecular imprinting material were studied in detail. The results show that the template molecule could significantly affect the pore volume, specific surface area, and hydroxyl density of mesoporous materials. These properties further affect the performance of the sensor. This study provides a valuable case study for the design of sensitive materials.Keywords:gas sensor;molecularly imprinted materials;dimethyl methyl phosphonate;surface acoustic wave
研究领域:
化学传感
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）