Reactive dye Ostazine Black V-B: determination in the dye-bath and hydrolysis monitoring by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry

Monitoring the hydrolysis of Ostazine Black V-B reactive dye was found to be possible by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOFMS). All the desired substances were identified in a mixture of the dye-bath. The process of the substrate reactive dye hydrolysis was qualified with hydrolysis rate constants k(1) (2.0 +/- 0.3 h(-1)) and k(2) (0.6 +/- 0.1 h(-1)). The method developed is important for the dyeing industry and for following the colouration process.