Tag Archive for: lipid

QCMD in Lipid Research

QCMD in Lipid Research Tech Note

/in , /by

October 15th 2020: AWSensors is pleased to invite you to take a look to its Technology Note entitled “QCMD in Lipid Research”.

Summary of the Note

QCMD is a label-free surface-analytical technique based on a quartz resonator excited to oscillate at its resonance frequency on one or more overtones. Resonators can have various coatings: gold (Au), silica (SiO2), titania (TiO2), etc. It works in aqueous media or organic solvents and is therefore widely used for studying solid/liquid interfaces. At each overtone, QCMD measures changes in the resonance frequency and energy dissipation due to the processes occurring at the resonator surface. Examples of such processes include formation of a film or changes in the geometrical or physical properties of the film.

The key feature that makes QCMD useful in lipid research is its ability to distinguish between different geometries and topologies of lipidic assemblies at interfaces, for example, homogenous solid-supported bilayers or monolayers vs. adsorbed liposomes or other structures (such as cubosomes) without relying on fluorescent or deuterated labels but by relying on the combination of the frequency and dissipation.

QCMD in Lipid Research

Introduction

Lipid-related QCMD work can be grouped into several topics, with a total of more than a thousand publications:
• Studies focusing on the interactions between lipids and surfaces.
• Studies focusing on the properties of the lipids, such as their phase behavior, adsorbed liposome deformation, etc.
• Studies examining interactions between lipids and membrane-binding proteins, peptides or viruses. Particularly interesting is that QCMD offers a way to study clustering of membrane-bound proteins.
• Studies focusing on the interactions of lipids with polymers or with nanoparticles.

 

Continue reading by downloading the full Technology Note (below) …

Download the Full Technology Note

You can download the full Note in pdf format through this link. A list of our Technology Notes can be found on our Technology Web Page.

SLB

Lipid Bilayers New Application Note

/in , /by

May 15h 2020: AWSensors is pleased to announce the release of its new Application Note on Supported Lipid Bilayers (SLB) entitled “Supported Lipid Bilayer formation followed at low- and high-fundamental frequencies“.

Summary of the Note

The process of supported lipid bilayer (SLB) formation from adsorbed liposomes is a robust biophysical system that is used in laboratories all over the world. Here, it is used to test AWSensors Quartz Crystal Microbalance with Dissipation measurement (QCMD) equipment and high fundamental frequency QCMD sensors. It is shown that the AWSensors QCMD system correctly and quantitatiely reports the frequency and dissipation changes associated with the SLB formation on high- and low-fundamental frequency SiO2-coated sensors. Some differences between the two types of sensors are highlighted. SLB

Introduction

Quartz crystal microbalance with dissipation measurement, or QCMD, has become a popular technique for research in such disparate fields as material science, biophysics, electrochemistry, and immunosensing. [1] One of the reasons for the wide range of applicability and popularity of QCMD is its ability to provide information about molecular organization (topology and geometry) at solid/liquid interfaces. Specifically, it was shown how the combination of frequency and dissipation could distinguish between different surface-immobilized lipidic assemblies: adsorbed liposomes and supported lipid bilayers (SLBs; Figure 1).[2] This allowed the process of SLB formation from liposomes on SiO2-coated QCMD sensors to be followed in situ.[2] Subsequent studies further showed how the combination of frequency and dissipation measurements on various overtones could be used to study adsorbed liposome deformation [3,4] and detect mutations through the analysis of DNA conformation and length. [5, 6]

Continue reading downloading the full Application Note (below) …

Download Full Application Note

You can download the full Application Note in pdf file from this link or download it from our Applications Web Page where you can find this and the rest of our Application and Technology Notes.