石英晶体微天平测量表面或附近发生的质量和黏度变化过程。 仪器读取5MHz/AT切割石英晶体的共振频率和电阻。共振频率变化与沉积于石英晶体表面的物质质量成线性关系。共振时的电阻随与表面接触物质(膜或液体)的黏/弹性而变化。 作为一种称重仪器,QCM200/100可以测量的质量范围从微克到小于一纳克。检测极限可以响应到原子亚单层。 构象变化的观察,比如相转换、膨胀和交联可以轻易实现。 特殊的重负载设计(5 kΩ),使得仪器在含量大于88%(重量比)的甘油水溶液中仍能保持振荡状态。因此成为研究损耗膜和高黏度液体的理想工具。 QCM200高灵敏度石英晶体微天平,可单独使用,也可与任何型号的ivium仪器连接,构成“电化学石英晶体微天平-EQCM”
主要参数:
* 晶振频率:5MHz;
* 频率分辨率:0.01Hz;
* 门时间:0.1秒、1秒、10秒;
* 质量分辨率:0.177ng/cm2;
* 电阻范围:0~5000 Ohm;
标准配置:铬/金晶体电极3个,控制器1个、振荡器1个、石英固定探头1个、软件一个 Frequency Measurement Display resolution 0.01 Hz (10 second gate) 0.1 Hz (1 second gate) 1.0 Hz (0.1 second gate) Gate time 0.1 s, 1 s, 10 s, user-selectable Int. timebase stability <2 × 10–9 Allan Variance (typ.) Int. timebase accuracy ±1.5 ppm Analog output ?f output ±10 V full scale (20-bit) Ranges ±200 kHz, ±100 kHz, ±50 kHz, ±20 kHz, ±10 kHz, ±5 kHz, ±2 kHz Frequency output Frequency 5 MHz (nominal) Level TTL (square wave) Source impedance 50 ? Ext. timebase input Frequency 10 MHz Level 1 Vpp (nominal) Resistance Measurement Resistance display Range 0 to 5000 ? Resolution 5 digits: 0.001 ? for R < 100 ? 0.01 ? for 100 ? ≤ R < 1000 ? 0.1 ? for 1000 ? ≤ R < 5000 ? Conductance output (Vc) Resistance R = 10,000 × (10–Vc/5) – 75 ? Resistance range 0 to 5000 ? Voltage level 0 to 10.625 VDC, log scale Impedance 1 k? Capacitance Cancellation Range 10 pF to 40 pF (20 pF nominal) Limit 0.01 pF Quartz Crystals (polished) Frequency 5 MHz, AT-cut, plano-plano Diameter 1 inch Electrodes Cr/Au (Ti/Au, Ti/Pt, In Sn oxide opt.) Physical Analog connectors BNC Interface RS-232, 9600 baud Crystal holder Material Holder: Kynar?, O-ring: Viton? Cable Cat-5, 3 ft. Dimensions, weight 10.6" × 2" × 7" (WHD), 2 lbs. Operating temperature 0 °C to 40 °C Power 15 W, 100/120/220/240 VAC, 50/60 Hz Warranty One year parts and labor on defects in materials and workmanship Ordering Information QCM200 Controller, oscillator, 3 crystals, holder and software O100FC Axial flow cell O100RXO Replacement oscillator electronics O100RH Replacement crystal holder O100CCB Crystal cleaning basket O100RX1 Chrome/gold crystals (qty. 10) 钛/金晶体 O100RX3 Titanium/gold crystals (qty. 10) 铬/金晶体 O100RX4 Titanium/platinum crystals (qty. 10) 钛/铂晶体
英文介绍: Features QCM200 Quartz Crystal Microbalance
The QCM200 Quartz Crystal Microbalance measures mass and viscosity in processes occurring at or near surfaces, or within thin films. This system includes a controller, crystal oscillator electronics, crystal holder, three quartz crystals, and Windows / Mac software.
The instrument reads the resonant frequency and resistance of a 5 MHz, AT-cut quartz crystal. The resonant frequency changes as a linear function of the mass of material deposited on the crystal surface. The resistance at resonance changes with the viscosity / elasticity of the material (film or liquid) in contact with the crystal surface.
As a gravimetric instrument, the QCM200 can measure mass ranging from micrograms to fractions of a nanogram. Detection limits correspond to submonolayers of atoms. Observations of conformational changes, such as phase transitions, swelling, and cross-linking, can easily be made.
Specifically designed to handle heavy loads (up to 5 kΩ), the instruments will maintain oscillation in aqueous solutions containing over 88 % glycerol (w/w %). It is ideal for studies involving lossy films and highly viscous liquids. Self-Assembled Monolayer BSA Adsorption to Gold
The QCM200 is a stand-alone instrument with a built-in frequency counter and resistance meter. Series resonance frequency and resistance are measured and displayed, and there is an analog output proportional to frequency which can be used to interface with a potentiostat. The QCM200 can be operated from the front panel or a PC using the RS-232 interface. Windows and MacIntosh software is provided for real-time data acquisition, display, analysis and storage. Both frequency and resistance trends can be viewed. User-tags are provided to time-stamp important events.
The stability and accuracy of the QCM200 are ideal for most experiments. For special applications requiring optimum long-term frequency stability, a precision timebase, such as the FS725 Rubidium Frequency Standard, can be connected to the external 10 MHz input. Immunosensor - Antigen-Antibody Interaction
QCM Electronics
A unique automatic gain control circuit provides the quartz crystal with the required signal amplitude to overcome viscoelastic losses and achieve series resonance. It also monitors the energy dissipated by the sensor, which is used to determine the series resistance of the crystal. The controller provides power to the crystal oscillator electronics, and includes a potentiometer for canceling shunt capacitance. Proper capacitance cancellation is required to assure true series resonance operation of the crystal oscillator, and to eliminate frequency and resistance errors.
In the QCM200, the digital controller also contains a frequency counter with 0.01 Hz resolution for accurate frequency measurements, and a resistance meter with 5 digits of resolution covering a range of 0 to 5000 Ω. Crystal Holder with Flow Cell
Crystals, Holder and Flow Cell
The QCM200 uses a 5 MHz, 1" diameter, AT-cut quartz crystal wafer with circular electrodes on both sides. Crystals are available in a variety of materials. The crystal holder is a rugged, compact, easy to use fixture. The holder and all crystals may be used in liquid or gas environments.
An optional axial flow cell adapter attaches to the standard crystal holder. This provides an easy way of interfacing the QCM to a flow injection analysis system.
EQCM EQCM - Frequency Measurement
For EQCM applications, an analog output proportional to frequency shift may be directly connected to a potentiostat or galvanostat. Only the front-surface electrode of the crystal is exposed to the solution. This electrode is also transformer isolated, as required for EQCM operation.
The figure below illustrates a typical EQCM experiment. The frequency analog output of the QCM controller is connected to the potentiostat A/D input. The potentiostat digitizes the voltage, and it's software displays relative frequency changes synchronous with the electrochemical data. The versatile QCM200 can be easily integrated into any custom 5 MHz crystal based EQCM setup.
In the Lab
The QCM200 is a valuable research tools for applications ranging from pure surface science to biochemistry. Quartz crystals can be pre-coated with any thin film material including organic polymers, hydrogels, composites, ceramics, biomolecules, bacteria and living cells. This provides unlimited potential for the development of novel gas and biological sensors.
The quartz crystal microbalance is an essential addition to any biological laboratory. The data from a QCM perfectly complements that obtained from other techniques, such as surface plasmon resonance (SPR) and atomic force microscopy (AFM), aiding in the analysis of complex biological interactions. QCM200 Data Acquisition Software
QCM200 Software
A Windows/Mac software program is included to facilitate remote operation and simplify data acquisition.
Applications
Immunosensors Sorption sensors Moisture analyzers Particulate monitors Contamination monitors Electrovalency measurements Hydrogen absorption on metal films Bubble formation Redox and conductive polymer research Double-layer characterization Corrosion studies Surface oxidation DNA and RNA hybridization studies Antigen-antibody reactions Protein adsorption Detection of virus capsids, bacteria, mammalian cells Biofouling and antifouling Biomembranes and biomaterials Protein-protein interactions Self-assembled monolayers (SAMs) Molecularly imprinted polymers (MIPs) Langmuir/Langmuir-Blodgett films Laser ablation, desorption and breakdown studies MEMS nanomaterials Intelligent biomaterials. Specifications: Frequency Measurement Frequency display Resolution 0.01 Hz (10 second gate) 0.1 Hz (1 second gate) 1.0 Hz (0.1 second gate) Gate time 0.1 s, 1 s, 10 s, user-selectable Measurement (using internal timebase) Stability <4 × 10-9 Allan Variance (typ.) Accuracy ±1.5 ppm Analog output Δf output ±10 V full scale (20-bit) Ranges ±200 kHz, ±100 kHz, ±50 kHz, ±20 kHz, ±10 kHz, ±5 kHz, ±2 kHz Frequency output Frequency 5 MHz (nominal) Level TTL (square wave) Source impedance 50 Ω Ext. timebase input Frequency 10 MHz Level 1 Vpp (nominal) Resistance Measurement Resistance display Range 0 to 5000 Ω Resolution 5 digits: 0.001 Ω for R < 100 Ω 0.01 Ω for 100 Ω ≤ R < 1000 Ω 0.1 Ω for 1000 Ω ≤ R < 5000 Ω Conductance output (Vc) Resistance R = 10,000 x (10-Vc/5) - 75 Ω Resistance range 0 to 5000 Ω Voltage level 0 to 10.625 VDC, log scale Impedance 1 kΩ Capacitance Cancellation Range 10 pF to 40 pF (20 pF nominal) Limit 0.01 pF Physical Analog connectors BNC Interface RS-232, 9600 baud Dimensions 10.625" × 2" × 7" (WHL) Crystal holder Material Holder: Kynar?, O-ring: Viton? Cable type, length Cat-5, 3 ft. Dimensions, weight 10.6" × 2" × 7" (WHL), 2 lbs. Operating temperature 0 °C to 40 °C Power 15 W, 100/120/220/240 VAC, 50/60 Hz Quartz Crystals (polished) Frequency 5 MHz, AT-cut, plano-plano Diameter 1 inch Electrodes Cr/Au (Ti/Au, Ti/Pt opt.) |