Cell experiment:

Selected mouse brain samples from either cortical or striatal regions (100 mg wet weight) and neuroblastoma cells (SH-SY5Y) pellet derived from 25 cm2 flask are treated with 500 μL of 0.1 M HCl containing 0.2% TDGA, sonicated for 10 min (only for brain tissue), and then centrifuged at 14000 g for 30 min. The supernatant is freeze-dried. 50 μL of reaction buffer and 100 μL of 15 mM Dabsyl chloride are added to the tube and derivatized.

Dabsyl chloride is an amine derivatizing agent, able to give rise to stable products that can be easily monitored spectrophotometrically at 460 nm; Dabsyl chloride also used for labeling amino acids.

Dabsyl chloride can give rise to mono-Dabsyl and bis-Dabsyl derivatives in the presence of multiple amino groups. Furthermore with respect to OPA derivatization, Dabsyl chloride can react with primary and also with secondary amines[1].

[1]. Francioso A, et al. HPLC Determination of Bioactive Sulfur Compounds, Amino Acids and Biogenic Amines in Biological Specimens. Adv Exp Med Biol. 2017;975:535-549.