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A review of Quartz Crystal Microbalances for Space Applications
摘要： The aim of this work is a technical review about Quartz Crystal Microbalance (QCM) sensors used in space missions, i.e. Space Shuttle flights, i.e. NASA Space Transportation System (NASA STS) and satellite missions, that aimed at monitoring the contamination generated by outgassing processes of materials onboard satellites and sensitive payloads. The contamination processes are critical for scientific instrumentation (e.g. optics, telescopes, detectors) because scientific measurements and performances can be jeopardized or worsened by uncontrolled contamination. This issue has been addressed by the space agencies, e.g. NASA, ESA and JAXA that have implemented many different studies to monitor the material outgassing and degradation in space environment. During the past years, the QCM sensors have become the baseline solution for measuring material outgassing and characterizing the on-orbit contamination environment. This work summarizes the main QCM applications in Space and their findings, providing an overview of the sensors’ performances in terms of stability, power, data rate, measurement accuracy and resolution. Different QCM technologies will be compared highlighting the advantages of their use for the next space missions and instrumentations that require an accurate monitoring of contamination environment. In particular, due to more severe contamination requirements for next payloads and instrumentations, QCM sensors would be useful to estimate the cleanliness degree by evaluating the induced contamination and degradation on sensitive instrumentations.
关键词： quartz crystal microbalance,contamination monitoring,spacecraft contamination,molecular and particulate contamination,outgassing,satellite contamination
更新于2025-09-23 15:23:52
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Reduction and compensation of humidity measurement errors at cold temperatures using dual QCM humidity sensors based on graphene oxides
摘要： One of the difficulties in measurements of relative humidity in a variety of environments is temperature-dependence especially at cold temperatures. Here, we report on the reduction and the compensation of temperature effects on humidity measurements using dual humidity sensors based on quartz crystal microbalance (QCM). Graphene oxide film is coated on quartz crystals as a humidity sensing layer for the detection of water sorption by the change of resonance frequency. Relative humidity in a test chamber, where dual QCM humidity sensors are located, is precisely controlled using a humidity generator at the temperature range from 20 °C to ?60 °C. It is found that single QCM humidity sensors measure humidity significantly higher than reference relative humidity by the generator as temperature is lowered due to the temperature-dependent resonance of quartz crystals. In an attempt to cancel out the temperature-dependent oscillation of QCM sensors, the ratio of resonance frequencies of dual QCM humidity sensors is used. Consequently, temperature-dependent errors in humidity measurement at low temperatures are evidently reduced. For the compensation of the remaining errors in the humidity measurement by dual QCM humidity sensors, a single formula is empirically obtained. After the compensation of low temperature effects, the dual QCM humidity sensors provide the measurement capability in terms of residual errors less than 1.1%rh throughout temperatures from 20 °C to ?60 °C. This study provides a useful insight to extend the applicability of QCM-based humidity sensors to environments with cold temperatures.
关键词： Compensation,Graphene oxide,Cold temperature,Quartz crystal microbalance,Humidity measurement,Humidity sensor
更新于2025-09-23 15:23:52
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Haloalkanes and aromatic hydrocarbons sensing using Langmuir–Blodgett thin film of pillar[5]arene-biphenylcarboxylic acid
摘要： Here, a pillar[5]arene derivative including biphenylcarboxylic acid groups was designed for obtaining a macrocycle with an ideal cavity for volatile organic compounds. The pillar[5]arene-biphenylcarboxylic acid (P5-BPCA) based Langmuir-Blodgett (LB) thin films were produced onto 50 nm thick gold-coated glass and 3.5 MHz quartz crystal substrates to form a thin film chemical sensor element. Surface plasmon resonance (SPR) and Quartz crystal microbalance (QCM) techniques were employed to characterize all the P5-BPCA LB thin film layers. The mass of LB film layer loaded onto a quartz crystal and the resonance frequency shifts per layer were determined to be 711.71 ng per layer (2.68 ng mm?2) and 48.24 Hz per layer, respectively. The P5-BPCA LB thin film sensor element was exposed to various haloalkane and aromatic hydrocarbon vapors. The sensitivities of the P5-BPCA LB film sensor were determined between 1.776 and 3.976 Hz ppm-1. Sensitivity with detection limits were obtained between 0.754 and 1.689 ppm against organic vapors. The results showed that P5-BPCA LB thin film was highly selective with a large response to chloromethane vapor.
关键词： Quartz Crystal Microbalance,Pillararene,Langmuir-Blodgett,Volatile Organic Compounds,Swelling,Surface Plasmon Resonance
更新于2025-09-23 15:23:52
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Humidity sensing properties of metal organic framework-derived hollow ball-like TiO2 coated QCM sensor
摘要： This paper demonstrates three kinds of TiO2 with hollow ball, nanosphere, and nanoflower nanostructures coated quartz crystal microbalance (QCM) humidity sensors, which were synthesized by metal organic framework (MOF)-derived, hydrothermal and solvothermal route, respectively. The compositional and morphological characteristics of three kinds of TiO2 nanostructures were characterized by means of X-ray diffraction (XRD), specific surface area analysis (BET), scanning electron microscopy (SEM) and water contact angle measurement. We found that the surface structure plays a crucial role in the humidity-sensing response properties of QCM sensors. The humidity sensing experiment was performed at room temperature. The MOF-derived hollow ball-like TiO2 coated QCM sensor exhibited excellent humidity sensing characteristics over a wide RH range (0%-97%RH), such as high sensitivity (33.8 Hz/%RH), good repeatability and short dynamic response/recovery times (5 s/2 s). In addition, Langmuir adsorption model was developed to explain the humidity-sensing properties of the TiO2-based QCM sensor. This work proves that MOF-derived hollow-ball TiO2 is a potential candidate nanomaterial for humidity sensor fabrication.
关键词： humidity sensor,Langmuir adsorption model,quartz crystal microbalance,hollow ball-like TiO2
更新于2025-09-23 15:22:29
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Simple and ultrafast resonance frequency and dissipation shift measurements using a fixed frequency drive
摘要： A new method for determination of resonance frequency and dissipation of a mechanical oscillator is presented. Analytical expressions derived using the Butterworth-Van Dyke equivalent electrical circuit allow the determination of resonance frequency and dissipation directly from each impedance datapoint acquired at a fixed amplitude and frequency of drive, with no need for numerical fitting or measurement dead time unlike the conventional impedance or ring-down analysis methods. This enables an ultrahigh time resolution and superior noise performance with relatively simple instrumentation. Quantitative validations were carried out successfully against the impedance analysis method for inertial and viscous loading experiments on a 14.3 MHz quartz crystal resonator (QCR). Resonance frequency shifts associated with the transient processes of quick needle touches on a thiol self-assembled-monolayer functionalised QCR in liquid were measured with a time resolution of 112 μs, which is nearly two orders of magnitude better than the fastest reported quartz crystal microbalance. This simple and fast fixed frequency drive (FFD) based method for determination of resonance frequency and dissipation is potentially more easily multiplexable and implementable on a single silicon chip delivering economies of scale.
关键词： Quartz crystal microbalance,Dissipation shift,Realtime monitoring,Acoustic sensor,Resonance frequency shift,Time resolution of biomolecular process measurement
更新于2025-09-23 15:21:21
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Highly sensitive and selective estimation of aspartame by chitosan nanoparticles–graphene nanocomposite tailored EQCM-MIP sensor
摘要： Here, a molecularly imprinted electrochemical quartz crystal microbalance (MIP-EQCM) sensor for aspartame is developed by grafting the aspartame-imprinted polymeric matrix of chitosan on gold-coated quartz crystal electrode. Chitosan nanoparticles being biocompatible, biodegradable and also having large surface area provide a better platform by forming a well-dispersed composite suspension with graphene. Additionally graphene facilitates direct electron transfer to electrode surface for electrochemical study because of having enhanced electrical conductivity. This EQCM-MIP sensor was characterized by atomic force microscopy, contact angle measurements, cyclic voltammetry and differential pulse voltammetry (DPV). The obtained MIP showed high affinity to aspartame. A reliable method for analysis of aspartame in real and commercial samples was achieved by coupling EQCM-MIP with DPV. Linear relationship with R2 = 0.9749 (EQCM) and R2 = 0.9760 (DPV) on binding of aspartame at various concentrations was observed. Detection limit of 0.45 μg mL?1 (EQCM) and 0.07 μg mL?1 (DPV) of the fabricated sensor shows that high sensitivity and high selectivity among various structural analogues of aspartame were also achieved. The improved detection limit is promising for determination of trace amount of aspartame. This demonstrates good memory capacity of this EQCM sensor. High recovery percentage and applicability of EQCM-MIP sensor in real matrices and commercial samples offers good potential for various applications.
关键词： Electrodeposition,Aspartame,Quartz crystal microbalance,Graphene,Chitosan nanoparticles,Molecular imprinting
更新于2025-09-23 15:21:21
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Target sequence recognition by a light-activatable bZIP factor, Photozipper
摘要： Photozipper (PZ) is a light-activatable basic leucine zipper (bZIP) protein composed of a bZIP domain and a light-oxygen-voltage-sensing domain of aureochrome-1. Blue light induces dimerization and subsequently increases the affinity of PZ for the target DNA sequence. We prepared site-directed PZ mutants in which Asn131 (N131) in the basic region were substituted with Ala and Gln. N131 mutants showed spectroscopic and dimerization properties almost identical to wild-type PZ, as well as an increase of helical content in the presence of the target sequence. Quantitative analyses by electrophoretic mobility shift assay and quartz crystal microbalance (QCM) measurements demonstrated that the half-maximal effective concentrations of N131 mutants to bind to the target sequence were significantly higher than those of PZ. QCM data also revealed that N131 substitutions accelerated the dissociation speed without affecting the association speed, suggesting that a base-specific interaction of N131 occurred after the association between PZ and DNA. Activation of PZ by illumination decreased both the standard errors and the unstable period of QCM data. Optical control of transcription factors will provide new knowledge of the recognition of the target sequence.
关键词： LOV,DNA-binding,Quartz crystal microbalance (QCM),aureochrome,bZIP
更新于2025-09-23 15:21:01
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Immobilization of DNA on Quartz Crystal Microbalance Sensor Modified with Self-Assembled Monolayer of Thiol Derivative
摘要： In this study, we investigated the direct detection of DNA, without pretreatment, using a quartz crystal microbalance (QCM) sensor. This sensor is modified by a self-assembled monolayer of a thiol derivative that has an amino group as the terminal functional group. Contact angle values and the attenuated total reflectance Fourier transform infrared (ATR/FT-IR) spectra of the QCM sensors after immersion into an ethanol solution of thiol derivatives clearly showed that self-assembled monolayers of the derivatives were formed on the QCM sensors. Although QCM measurements using unmodified and carboxylic group-modified sensors could not detect DNA-Na salt, the sensor modified with amino groups could detect the DNA. This system can be used for the analysis of the interaction between DNA and DNA-binding proteins.
关键词： DNA,thiol derivative,quartz crystal microbalance,self-assembled monolayer
更新于2025-09-23 15:19:57
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[IEEE 2018 IEEE 13th Annual International Conference on Nano/Micro Engineered and Molecular Systems (NEMS) - Singapore, Singapore (2018.4.22-2018.4.26)] 2018 IEEE 13th Annual International Conference on Nano/Micro Engineered and Molecular Systems (NEMS) - A Miniature System for Classification and Concentration Detection of PM Based on 3D Printed Virtual Impactor and QCM Sensor
摘要： In this paper, we report a miniature system for separation and concentration detection of airborne particulate matter (PM) based on three-dimensional (3D) printed virtual impactor and quartz crystal microbalance (QCM) sensor. The virtual impactor is optimized by computational fluid dynamics (CFD) simulation to have a relatively small size of 24 × 24 × 10 mm3. The performance of the miniature PM monitoring system is characterized through classification and detection of silicon oxide powers with diameter ranging from 0.5 to 10 μm in a chamber. The experimental results show that particles smaller than cutoff diameter of 2.5 μm are separated by the virtual impactor according to their size and detected by the QCM sensor. Moreover, the resonant frequency of the QCM sensor shows a linear decrease with the increment of PM mass loading.
关键词： Particulate matter,Virtual impactor,Quartz crystal microbalance,Classification
更新于2025-09-19 17:15:36
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A novel quartz-crystal microbalance humidity sensor based on solution-processible indium oxide quantum dots
摘要： Having a large surface area, like the quantum con?nement e?ect also caused by the nano-level size of quantum dots (QDs), creates fantastic potential for humidity sensing. A high concentration of surface adsorption sites initiates an increased response. Porosity between QDs allows fast water vapor penetration and out?ow. Here, a quartz-crystal microbalance (QCM) humidity sensor was prepared using indium oxide (In2O3) QDs, synthesized via a solvothermal method. After the In2O3 QDs were directly spin-coated onto the QCM, an annealing process removed organic long chains and exposed more moisture adsorption sites on the surfaces of the QDs. The annealed QCM humidity sensor exhibited high sensitivity (56.3 Hz per %RH at 86.3% RH), with a fast response/recovery time (14 s/16 s). Long carbon chains were broken down, and hydrogen-bonded hydroxyl groups were chemisorbed to the QDs. The chemical reaction was reduced by these chemisorbed hydrogen-bonded hydroxyl groups. Mass change was mostly caused by fast multilayer physisorption. Thus, the transducer can e?ectively and precisely monitor the moisture from a person's breath. In2O3 QD-modi?ed QCM sensors demonstrate promising humidity-sensing applications in daily life.
关键词： indium oxide quantum dots,annealing process,solvothermal method,humidity sensor,quartz-crystal microbalance
更新于2025-09-16 10:30:52