Specialty Application Indicator Versions
Posted on Sun, Feb 21, 2010
TEFLabs offers both low affinity(lowAff) and near membrane (NearMem) specialty application versions of multiple calcium indicators.
Low Affinity
Low affinity calcium indicators have several advantages over their high affinity counterparts:
- Fluorescent response does not saturate at micromolar calcium levels
- Reduced buffering of intracellular calcium and reduced perturbation of calcium transients
- Faster dissociation from calcium allows for measurement of shorter-lived transients.
Our low affinity indicators are based on the electron-withdrawing effect of fluorine on the affinity of the parent dye. Their Kds shift from the nanomolar to the micromolar range, with high selectivity for calcium over magnesium, unlike their APTRA based counterparts. We offer Fura-2 LowAff (Cat.# 0135 formerly Fura-2 FF), Indo-1 LowAff (Cat.# 0138 formerly Indo-1 FF), Fluo-2 LowAff, and Asante Calcium Red LowAff (Cat.# 3050) low affinity indicators.
Near Membrane
The near-membrane calcium indicators continue to be highly successful in their niche applications. Unlike other hydrophobic indicators, these have a piperazine collar to latch into the membrane, leaving the chelating portion to measure calcium in the gates and not lost in the membrane. TEFLabs offers Fura-2 NearMem (Cat.# 0125, formerly FFP-18), Indo-1 NearMem (Cat.# 0127, formerly FIP-18 ). Fluo-2 NearMem, and Asante Calcium Red NearMem (Cat.# 3200) are currently under development.