Quantum Dots (Qdots) Application Guide
Basics of Qdots
Qdots (or quantum dots) are fluorescent crystalline constructions that are most strongly absorbent in the UV to violet region of the spectrum, but emit, depending on their size, through the rest of the visible and near-IR.
Chroma worked specifically with the original Qdot Corporation during the initial development of Qdots to generate filter sets that were optimal for their detection. Chroma carries a number of Qdot-specific filter sets that differ in the width of excitation and emission light transmitted through the various optics, depending on the needs of the user.
Qdots are commercially available from several manufacturers and can also be engineered for specific emission properties depending on the application.
Filter Requirements for Qdots
The most common Qdot filter sets contain a shortpass excitation filter that transmits ~340-460 nm and a 40 nm-wide bandpass emission filter centered on the peak emission of the individual Qdot (e.g. 565/40 or 565+/-20 nm for Qdot 565).
In some applications, narrower excitation bands (e.g. 405/90 or 405+/-45 nm, or 420/40 or 420+/-20 nm) are used in order to minimize the impact of UV excitation light-driven phototoxicity in live cell imaging, or in instances where UV excitation is not desired.
Additional Resources
Still Have Questions?
Our applications team works with Qdot setups across most major commercial platforms. Tell us your instrument and fluorochromes and we'll point you in the right direction.
