Separation type: Bridge Ion Separation Technology, or BIST™ by SIELC Technologies

Brilliant Black BN (Food Black 1, E151) and Chicago Skye Blue are two azo dyes with the unique property that they have 4 sulfonate groups. Using SIELC’s newly introduced BIST™ method, Brilliant Black BN and Chicago Sky Blue can be retained and separated into its component compounds easily on a negatively-charged, cation-exchange BIST™ A+ column. There are two keys to this retention method: 1) a multi-charged, positive buffer, such as N,N,N’,N’-Tetramethyl-1,3-propanediamine (TMDAP), which acts as a bridge, linking the negatively-charged anion analytes to the negatively-charged column surface and 2) a mobile phase consisting mostly of organic solvent (such as MeCN) to minimize the formation of a solvation layer around the charged analytes. While both of these sulfonated dyes have the same charge, their molecular structure (and therefore charge distribution) differs just enough to allow them to be separated in a high-organic MP. 

Other positively-charged buffers that can generate BIST™ include DMP, Calcium acetate, and Magnesium acetate. Using this new and unique analysis method, Brilliant Black BN and Chicago Sky Blue can be retained and separated with high selectivity and great peak shape. This method can be detected and is compatible with ELSD, CAD, and Mass Spectrometry (LC-MS).

BIST A+ Column 4.6x150mm 5um 100A

Condition

Column	BIST™ A+, 4.6×150 mm, 5µm, 100A
Mobile Phase	Gradient MeCN
Buffer	TMDAP phosphate – 5 mM  pH 4.0
Flow Rate	1.0 mL/min
Detection	Vis 600 nm

Description

Class of Compounds	Dyes
Analyzing Compounds	Chicago Sky Blue