The quartz-crystal microbalance (QCM) technique was applied to investigate the interaction of tea catechins with lipid bilayers. The association constants obtained from the frequency changes of QCM revealed that (-)epicatechin gallate and (-)epigallocatechin gallate interacted with 1,2-dimyristoyl-sn-glycero-3-phosphocholine ca. 1000 times more strongly than (-)epicatechin and (-)epigallocatech...

This grant supported our work in the detection of pathogenic whole cells. We used a surrogate for bacillus anthracis known as bacillus subtilis and detected is via an acoustic immunoassay. Antibodies for b. subtilis were obtained from Dr. J. Kearny of the University of Alabama at Birmingham and were immobilized onto the surface of a quartz crystal microbalance (QCM). The data from a series of e...

The determination of fibrinogen levels is one of the most important coagulation measurements in medicine. It plays a crucial part in diagnostic and therapeutic decisions, often associated with time-critical conditions. The commonly used measurement is the Clauss fibrinogen assay (CFA) where plasma is activated by thrombin reagent and which is conducted by mechanical/turbidimetric devices. As qu...

QCM stands for `Query Certi cate Manager'; it is a software system that has been developed at the University of Pennsylvania as part of the SwitchWare project on active networks. QCM is a Public Key Infrastructure (PKI) intended to support secure maintenance of distributed data sets like Access Control Lists (ACL's) or public key certi cate repositories. An ACL is a list of `principals', identi...

This article reports that the kinetics of surface-initiated atom transfer radical polymerization can be quantified by the quartz crystal microbalance with dissipation (QCM-D) technique. The kinetics of in situ growth of poly(oligoethylene glycol methylmethacrylate) monitored on a gold-coated QCM-D sensor chip revealed that changes in the experimentally observed frequency (DeltaF) and dissipatio...

In order to support verification, validation and analysis of dynamic Operations Research (OR) models a method of testing models against data is required. In the case of the QCM qualitative reasoning system (QRS) this requires an extension to accommodate temporal data streams. This paper examines a number of temporal reasoning methods for QCM. On the basis of this a general methodology for evalu...

The effect of surface roughness on the response of the QCM has been considered, both theoretically and experimentally. A new theoretical approach to the description of the effect of roughness on the response of the QCM is proposed that accounts for the multiscale nature of roughness. Performing experiments in liquids having a wide range of viscosity and density made it possible to understand, f...

We have used novel microporous biphenylene-pillared layered silicates as receptors in a quartz crystal microbalance (QCM) for sensing toluene vapors. The silicate was successfully coated on a QCM electrode modified with 2-aminoethanethiol. The resultant electrode showed quantitative frequency responses due to enhanced adhesion between the silicate and the electrode. The silicate-coated electrod...

We demonstrate the combined use of liquid and air measurements with the quartz crystal microbalance (QCM) for quantitative analysis of multistep reaction procedures leading to immobilized proteins on solid surfaces. Reactions are conducted on the surfaces of QCM sensor crystals and are quantified by measurements of resonant frequency of the crystals before and after each reaction step. When rea...

Breath acetone serves as a biomarker for diabetes. This article reports 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF₄]), a type of room temperature ionic liquid (RTIL), as a selective sensing material for acetone. The RTIL sensing layer was coated on a quartz crystal microbalance (QCM) for detection. The sensing mechanism is based on a decrease in viscosity and density of the [bmim]...