Frequency Behavior of a Quartz Crystal Microbalance (Qcm) in Contact with Selected Solutions

Abstract

Abstract:A device was constructed to monitor viscosity of solutions using fundamental frequency of 9 MHz and 10 MHz quartz crystal. Piezoelectric quartz crystals with gold electrodes were mounted by O-ring in between liquid flow cell. Only one side of the crystal was exposed to the solutions which were pumped through silicon tube by a peristaltic pump. The measured frequency shift was observed in order to investigate the interfacial behavior of some selected solution in contact with one surface of Quartz Crystal Microbalance (QCM). An analysis of the interaction between an AT-cut quartz crystal microbalance and various liquid system of analytical interest is presented. The analysis which includes piezoelectric effects and other influences; liquid properties, experimental conditions and the characteristic of the solution are reported. Oscillation in distilled water is taken as a reference. The frequency change caused by the density ( , gcm 3 ) and viscosity ( , gcm 1 s 1 ) were found to be proportional to the square root of the product, ( ). The result suggested that analysis of small frequency shifts during EQCM studies needs to account for changes in and of the solution.Generally, all the liquid tested showed an increment of the frequency shift with increasing content of solutes. For each solution, the frequency was recorded as the concentration increases from distilled water to a very concentrated solution. The frequency measurements carried out for saccharide solution produces the maximum changes of frequency shift compared with other solutions.

QCM as Cell-Based Biosensor

“…The TEER value continued to rise until the 5th day (arrow f: resistance was from 40 to 55 KΩ). The change of weight affecting the quartz resonant frequency and can be detected in the range for about 0.25 μm above the quartz surface in a solution state (Talib et al, 2006). The affected depth was only one-tenth of cells in thickness, the change of frequency can be detected with the cells grown on the surface when cells attached on QCM, and the change of frequency cannot monitor the process of cell metabolism.…”

“…Talib et al (2006) reported that different QCM solutions produce different signal frequencies. But there is only a constant distance at the electrode surface in which QCM can detect the change of solution.…”

Applying the Quartz Crystal Microbalance Technique to Detect the Epithelial Cell Tight Junction Integrality of Caco-2 Cells

“…If the weight of electrode surface is constant, but liquid viscosity-density change in the solution above the QCM crystal surface will also produce a frequency change. Talib et al (2006) reported that different QCM solutions produce different signal frequencies. But there is only a constant distance at the electrode surface in which QCM can detect the change of solution.…”

Improve the Data Acquisition System of a QCM Sensor by Increasing the Sampling Rate of Frequency and Amplitude

“…5 Equations (1) and (2) are unable to meet specificities of different experiments. Thus density and viscosity will influence the resonance and cause frequency change of QCM in liquid phase.…”