Product Overview

The Q-Sense Initiator is a QCM-D instrument for high sensitivity mass detection. It is a single channel system with a fixed flow module which holds the sensor. A peristaltic pump connected to the flow module controls the loading of the sample on the sensor surface. Changing the buffer/substrate solutions enables a wide range of experimental conditions.

The system software controls the instrument operation and enables the detection of mass changes. There is quantification of rigid film mass. The Q-Sense Initiator has a fixed flow module so is not compatible with the other measurement modules. It is compatible with the whole range of Q-Sense sensor surfaces.

What is QCM-D?

Quartz Crystal Microbalance with Dissipation (QCM-D) is a label free technique that provides real time analysis of thin film formation and interactions. The film is formed on a sensor which consists of a thin quartz disc sandwiched between a pair of electrodes. An AC voltage oscillates the sensor at high frequency. The solution of film material flows across the surface of the sensor and molecular layers of film build up on the surface. The sensor mass changes and so does its oscillation frequency. The frequency change is related to mass/thickness of the film.Mass changes can be measured with nanogram sensitivity – less than 1% of a protein

Frequency-mass. If the film is thin and rigid the sensor oscillation frequency can be used in the Sauerbrey relation to calculate the total mass on the sensor surface. If the film material density is known then the film thickness can be calculated.

Dissipation-viscoelasticity. Viscoelastic films dampen the sensor oscillation more than rigid films and the Sauerbrey relation is no longer valid. By measuring the dissipation rate and driving the sensor at multiple harmonic frequencies it is possible to calculate the values of film thickness, viscosity, elasticity and density.

Applications include protein conformational changes, lipids, polymers and whole cells. It is possible to determine the water content of molecular layers. Interactions can be studied on many sensor coatings such as gold and polymers.