scholarly journals Frequency-shift vs phase-shift characterization of in-liquid quartz crystal microbalance applications

2011 ◽  
Vol 82 (6) ◽  
pp. 064702 ◽  
Author(s):  
Y. J. Montagut ◽  
J. V. García ◽  
Y. Jiménez ◽  
C. March ◽  
A. Montoya ◽  
...  
Keyword(s):  
Phase Shift ◽  
Frequency Shift ◽  
Quartz Crystal Microbalance ◽  
Quartz Crystal

Characterization of Jumping-Droplet Condensation on Nanostructured Surfaces With Quartz Crystal Microbalance

2017 ◽  
Author(s):  
Junwei Su ◽  
Hamed Esmaeilzadeh ◽  
Chefu Su ◽  
Majid Charmchi ◽  
Marina Ruths ◽  
...  
Keyword(s):  
Frequency Shift ◽  
Quartz Crystal Microbalance ◽  
Microscopic Observation ◽  
Quartz Crystal ◽  
Structured Surfaces ◽  
Nanostructured Surfaces ◽  
Acoustic Technique ◽  
Flow Condensation ◽  
Droplet Condensation

The spontaneously jumping motion of condensed droplets by coalescence on superhydrophobic surfaces has been an active area of research due to its great potential for enhancing the condensation efficiency. Despite a considerable amount of microscopic observations, the interfacial wetting characterization during jumping-droplet condensation is still notably lacking. This work focuses on applying a novel acoustic sensor - quartz crystal microbalance (QCM), to characterize the interfacial wetting on nanostructured surfaces during jumping-droplet condensation. Copper oxide nanostructures were generated on the surface of QCM with a chemical etching method. Based on the geometry of the nanostructures, we modified a theoretical model to reveal the relationship between the frequency shift of the QCM and the wetting states of the surfaces. It was found that the QCM is extremely sensitive to the penetrated liquid in the structured surfaces. Then, the QCM with nanostructured surface was tested on a customed flow condensation setup. The dynamic interfacial wetting characteristics were quantified by the normalized frequency shift of the QCM. Combined with microscopic observation of the corresponding drop motion, we demonstrated that partial wetting (PW) droplets with an about 25% penetrated area underwent spontaneously jumping by coalescence. However, the PW droplets no longer jumped when the penetrated area exceeds 50% due to the stronger adhesion between liquid and the surface. It shows that the characterization of the penetrated liquid in micro/nanostructures, which is very challenging for microscopic observation, can be easily carried out by this acoustic technique.

Quartz crystal microbalance characterization of electrochemical doping of polyaniline films

1993 ◽  
Vol 61 (3) ◽  
pp. 291-296 ◽  
Author(s):  
R.M. Torresi ◽  
S.I.Cordoba de Torresi ◽  
C. Gabrielli ◽  
M. Keddam ◽  
H. Takenouti
Keyword(s):  
Quartz Crystal Microbalance ◽  
Quartz Crystal ◽  
Electrochemical Doping ◽  
Polyaniline Films

scholarly journals The adsorption of phosphate-buffered saline to model films composed of nanofibrillated cellulose and gelatin

2019 ◽  
Vol 17 (1) ◽  
pp. 228080001982651 ◽  
Author(s):  
Sedat Ondaral ◽  
Elif Çelik ◽  
Orçun Çağlar Kurtuluş
Keyword(s):  
Frequency Shift ◽  
Functional Groups ◽  
Quartz Crystal Microbalance ◽  
Quartz Crystal ◽  
Nanofibrillated Cellulose ◽  
Adsorption Rate ◽  
Carboxyl Groups ◽  
Trend Model ◽  
Phosphate Buffered Saline

Phosphate-buffered saline (PBS) adsorption on model films composed of gelatin and nanofibrillated celluloses (NFCs) with different aldehyde and carboxyl contents was studied by means of the quartz crystal microbalance with dissipation (QCM-D) technique in this study. The results showed that frequency shift (Δ f) due to PBS adsorption increased with increasing gelatin content to 50% in NFC-containing films. The dissipation shift and adsorption rate of PBS followed the same trend. Model films with NFC-1 having 1.22 mmol/g aldehyde and 0.6 mmol/g carboxyl groups adsorbed more PBS than those consisting of NFC-2 with 0.25 mmol/g aldehyde and 1.15 mmol/g carboxyl groups except for film composed of 50% gelatin. However, adsorption rate of PBS was found to be slower for NFC-1 containing film because the acetal and amidol bonds formed by functional groups in the network of cellulose and gelatin needed more time to let PBS migrate into the films.

A Quartz Crystal Microbalance Characterization of Metal‐Oil Interfaces and Interactions with Wax Molecules

2008 ◽  
Vol 29 (5) ◽  
pp. 775-782 ◽  
Author(s):  
Kristofer Paso ◽  
Thomas Kompalla ◽  
Narve Aske ◽  
Johan Sjöblom
Keyword(s):  
Quartz Crystal Microbalance ◽  
Quartz Crystal

SURFACE PLASMON RESONANCE SPECTROSCOPY AND QUARTZ CRYSTAL MICROBALANCE STUDY OF PROTEIN-DNA INTERACTIONS IN HORMONE RECEPTOR BIOLOGY

COSMOS ◽  
2009 ◽  
Vol 05 (01) ◽  
pp. 79-95
Author(s):  
XIAODI SU
Keyword(s):  
Surface Plasmon Resonance ◽  
Surface Plasmon ◽  
Quartz Crystal Microbalance ◽  
Conformational Changes ◽  
Plasmon Resonance ◽  
Quartz Crystal ◽  
Resonance Spectroscopy ◽  
Dna Interactions ◽  
Protein Dna Interactions

Surface plasmon resonance (SPR) spectroscopy and quartz crystal microbalance (QCM) are surface sensitive analytical techniques capable of real-time monitoring of biomolecular interactions. In this article we review our past work on the use of these two techniques for studying protein–DNA interactions, exemplified with estrogen receptors (ER) and their response elements (ERE). Various assay schemes have been developed for a comprehensive characterization of ER–ERE interactions in terms of sequence specificity, binding affinity, stoichiometry, ligand effects on binding dynamics and conformational changes in the proteins and DNA. These are all important characteristics underlining the mechanism of ER-mediated gene transcription. With these studies we have made the following demonstrations to describe the advantages of these two techniques, namely (i) SPR technique is superior and more versatile than conventional (electrophoretic mobility shift assay) EMSA for studying protein-DNA interactions; (ii) QCM is an alternative tool for studying conformational changes in protein–DNA complexes and (iii) combinational SPR and QCM analysis provides additional characterization of biomolecular films, e.g. film thickness, water content, and conformation rigidity etc.

Measurement of Solvent Vapor Absorption by Polydimethylsiloxane Using Quartz Crystal Microbalance

2008 ◽  
Author(s):  
W. W. F. Leung ◽  
C. Chao ◽  
C. H. Cheng ◽  
K. F. Lei ◽  
D. Ngan ◽  
...  
Keyword(s):  
Frequency Shift ◽  
Gas Sensor ◽  
Quartz Crystal Microbalance ◽  
Quartz Crystal ◽  
Specific Area ◽  
Small Mass ◽  
Crystal Oscillator ◽  
Solvent Vapor ◽  
Adsorbed Gas ◽  
Micro Electromechanical System

A new micro-electromechanical system (MEMS) gas sensor has been developed using quartz crystal microbalance (QCM) with adsorbent coated in form of nanofibers on the QCM sensor. The nanofibers with fiber diameter typically around 200–300 nm increases the specific surface area to enhance adsorption. The QCM is made to oscillate at its natural resonance frequency. Upon exposure of the gas sensor to a given gas, the adsorbed gas onto the nanofibers adds a small mass which changes the natural frequency of the oscillation. By detecting the frequency shift due to adsorption of a given gas, the presence of the gas is detected, and by measuring the frequency shift, the amount of gas being adsorbed at a given pressure and temperature is quantified via the Sauerbrey equation [1]. A circuit has been developed to read the frequency shift due to the energy dissipation in the QCM coated with Polydimethylsiloxane (PDMS) nanofibers under the environment of several solvent vapors. The developed circuit includes two crystal oscillator circuits, two QCM’s which are respectively 1MHz reference QCM and a coated QCM, RC filter and AND gates. The results of the frequency shift between the reference QCM and the coated QCM were recorded on the oscilloscope so as to investigate the relationships between the frequency shift and the amount of vapor adsorbed for different gases. Ultimately, Volatile Organic Compounds (VOCs) are the target to be monitored and a MEMS based sensor will be developed similar to the present QCM gas sensor discussed herein. This work provides the feasibility study for using nanofiber coating to enhance the adsorbent specific area and a stand-alone QCM sensor for making measurement.

Sign in / Sign up

Export Citation Format

Share Document