SETA BioMedicals

Fluorescence Correlation Spectroscopy (FCS):

Fluorescence Correlation Spectroscopy (FCS)

Fluorescence correlation spectroscopy (FCS) is a fluorescence microscoy-based technique that provides information on diffusion rate, absolute numbers and changes in particle fluorescence of fluorescently labeled molecules. FCS measures fluorescence intensity fluctuations due to diffusion of fluorescent molecules through the confocal volume element or other measurable changes in the confocal volume element. The fluctuations are correlated over time, yielding quantitative information on molecular mobility and local concentration. Confocal fluorescence microscopy measurements in cells allow studying the interactions and dynamics of biomolecules in their native environment. FCS has therefore become an important tool for various disciplines for following biological events and cellular processes.

SETA BioMedicals offers a number of highly photostable fluorescent labels for use with FCS applications. For a comprehensive list of our proprietary labels we refer you to our Seta dyes.

If you consider using FRET in combination with FCS in your application we refer you to FRET Applications, where we offer a series of FRET pairs with Forster distance from 40 – 80 Angstrom. Should you require a specific FRET pair that is not on the list please contact us.

Our newly developed Squaraine-rotaxanes are extremely bright and photostable and well-suited for FCS measurements. SeTau 647 is the brightest dye currently on the market for the Kr-ion laser. It combines a quantum yield of 60% with an extinction coefficient of 200,000 [M^-1.cm^-1]. Please contact us for more information.

Superior Squaraine-Rotaxane Labels for FCS:

Product	Lifetime	Pack Size	Product Code
SeTau 647-NHS	3.2	0.5mg	K9-4149-0.5mg
SeTau 647-di-NHS	3.2	0.5mg	K9-4142-0.5mg
SeTau 665-NHS	3.1	0.5mg	K9-4119-0.5mg
SeTau 665-di-NHS	3.1	0.5mg	K9-4113-0.5mg

Pricing and Availability
Ordering

Product Specifications:


			Excitation Light Sources								Free Dye					Dye Conjugate
Product Number	Product Name	Target Group	380	405	436	488	532	594	635	670	Solvent	λ_Ab max. [nm]	ε [M^–1cm^–1]	λ_Em max. [nm]	QY [%]	Carrier PB 7.4	λ_Ab max. [nm]	λ_Em max. [nm]	QY [%]
K8-3335	Seta-555-NHS	NH₂					•				PB 7.4	556	155000	570	12	IgG, D/P=1	654	571	23
K9-4112	SeTau-655-di-NHS	NH₂							•		PB 7.4	665	200000	673	25	IgG, D/P=1	657	675	31
K9-4113	SeTau-665-di-NHS	NH₂	•							•	PB 7.4	665	140000	715	62	IgG, D/P=1	664	709	43
K9-4142	SeTau-647-di-NHS	NH₂							•		PB 7.4	650	368000	694	65	IgG, D/P=0.5	649	691	58
K8-5035	Seta-650-NHS	NH₂							•		PB 7.4	651	172000	671	28	IgG, D/P=1	654	673	37
K9-4149	Seta-647-NHS	NH2							•		PB 7.4	649	200000	695	61	IgG, D/P=1	648	694	59
K9-4119	SeTau-665-NHS	NH2	•	•						•	PB 7.4	664	160000	712	53	IgG, D/P=1.2	653	716	50