What Is A Calcium Flux Assay?
A calcium flux assay is a type of biochemistry assay that uses an antibody to detect calcium ions. Calcium flux assays are useful for determining how the body regulates blood flow and can be used for various clinical studies.
Synthetic Indicators
The study of the dynamic behaviour of calcium (Ca2+) ions has been a key tool in neuroscience and physiology research. Ca2+ ion flux measurements have applications ranging from high-spatial resolution imaging of synaptic activity to drug discovery. In this article, we review recent advances in calcium assay techniques, including genetically encoded calcium indicators (GECIs) and synthetic calcium dyes. These technologies open new avenues for the study of cellular processes driven by calcium.
GECIs
GECIs are calcium indicators that can be used in both eukaryotic and microbial systems. In recent years, their applications have increased in popularity. They have also been used to improve Ca2+ detection methods. GECIs are similar to well-characterized synthetic dyes, but have additional advantages. These include their ability to track Ca2+ levels in multiple cell types, thereby improving high-throughput assays.
Flow Cytometry
Calcium ions play a key role in the activity of all muscle cell types. They also participate in many signal transduction pathways. Therefore, intracellular calcium levels are important indicators for cell activation and damage.
Flow cytometry has become a valuable tool for the study of calcium ion activity. However, these studies require careful design. A common approach to monitoring calcium ion levels is to use fluorescent dyes. In particular, o-cresolphthalein and Indo-1 probes have been used for Ca2+ flux measurements. These fluorescent indicators can be loaded into cells in the form of an acetoxymethyl ester.
FLIPR
A calcium flux assay has become a powerful tool for modern drug discovery. Hundreds of proteins are known to modulate the concentration of calcium ions. These changes are transduced into downstream cellular signals and affect a number of physiological processes. However, these assays are not able to directly measure the ion channel function of these receptors. In the past, synthetic calcium indicators have been used in these assays. Now, Molecular Devices has developed FLIPR Calcium Assay Kits that deliver pre-optimized reagents and a simple, homogeneous assay format.
GCaMP6s
It is a well-known fact that calcium is a key part of signalling pathways. One important tool in neuroscience research is the functional imaging of calcium. This involves the measurement of Ca2+ flux in eukaryotic cells. The most commonly used calcium indicators are fluorescent proteins.
Calcium indicators are divided into single-FP and radiometric varieties. Fluorescent FRET-based GECIs offer the benefits of radiometric performance with visible light readout. However, this method of Ca2+ tracking requires extensive post-data processing.