Letter to Researchers

Since 1992, TEFLabs’ mission has been to support more effective research.  In recent years, our focus has been to provide the widest range of fluorescent ion indicators and their specialized versions.  

We are very pleased to introduce five indicator families which dramatically extend your testing capabilities for sodium, potassium, and calcium ions.

Asante Natrium Green
is a new fluorescent sodium indicator that allows researchers to study sodium using the same equipment and methods developed over the last twenty years to study calcium with Fluo dyes.  Operating in the visible spectrum, it loads readily to give a bright and sensitive response to sodium.  SQI-Pr is a true sodium ionophore, with a selectivity of 100:1, to complement Asante Natrium Green.

Asante Potassium Green
is the potassium analog of Asante Natrium Green, with the corresponding ease of loading, brightness, and sensitivity to potassium.   

We offer both low and high affinity versions of these sodium and potassium dyes.

TEFLabs has taken several approaches to improving calcium indicators by addressing the key performance factors of brightness, loading, retention, accuracy, and response wavelength.

Asante Calcium Green is very bright and has extremely low leakage from cells, so that the use of probenecid is not necessary for most experiments.  In addition to supporting prolonged testing with its no-leak properties, its high sensitivity combined with large dynamic range should make it the most popular calcium indicator for both high throughput testing and cell research.

Asante Calcium Red exhibits red emission with a maximum at 650 nm and can be used either ratiometrically or non-ratiometrically, depending on the wavelength of excitation.  As with many red dyes, the brightness is relatively low, but the long wavelength response, independent from cellular autofluorescence and GFP emission, makes this indicator desirable for many applications.  Asante Calcium Near IR, an analog of this new indicator, can be excited at 635 nm with emission at 690 nm.

Fluo-2 Medium Affinity is a direct replacement for Fluo-4, but it is brighter, easier to load, and less expensive.   

We are always pushing the limits of our research to provide more innovative optical tools for the future of ion indicators. Please do not hesitate to engage us to address other ion indicator problems.

Thank you for your support over the years.


A.Minta, Ph.D
Founder and Chairman