Fluorochrome Selection Flashcards

Which fluorochrome has the highest quantum yield among commonly used dyes, making it ideal for detecting low-abundance antigens?

Answer: R-Phycoerythrin (PE)

PE has one of the highest quantum yields (~0.98) of commonly used fluorochromes, making it excellent for detecting low-abundance antigens.

When designing a multicolor panel, a marker with very high expression should be paired with a fluorochrome that has:

Answer: Low brightness

Highly expressed antigens should be paired with dim fluorochromes to prevent spillover from oversaturation overwhelming adjacent detector channels.

Which property of a fluorochrome directly determines the amount of spectral spillover into adjacent channels?

Answer: Emission spectrum width and tail

The width and tail of the emission spectrum determine how much signal from one fluorochrome bleeds into adjacent detector channels.

BV421 is best excited by which laser line commonly found on flow cytometers?

Answer: 405 nm violet laser

BV421 (Brilliant Violet 421) is optimally excited by the 405 nm violet laser and emits around 421 nm.

Which fluorochrome is most susceptible to photobleaching during extended acquisition times?

Answer: FITC

FITC is highly susceptible to photobleaching compared to more photostable alternatives like BV dyes or tandem conjugates.

In a panel using a UV laser (355 nm), which fluorochrome would be an appropriate choice for UV excitation?

Answer: BUV395

BUV395 (Brilliant Ultraviolet 395) is specifically designed for excitation with the 355 nm UV laser.

When multiplexing fluorochromes on the same laser, which parameter is most important to minimize spectral overlap?

Answer: Maximizing emission peak distance between dyes

Maximizing the distance between emission peaks of co-excited fluorochromes minimizes spectral overlap and reduces the need for high compensation.