Dyes with high affinity for diphtheria toxoid as promising affinity ligands for its industrial purification

MARTÍNEZ CERON MARÍA C.; GIUDICESSI, SILVANA L.; DOKMETJIAN, CHRISTIAN ; CAMPERI, SILVIA A.; CASCONE, OSVALDO

Current chromatography

BENTHAA SCIENCE PUBL LTD

Año: 2018 vol. 5 p. 72 - 76

2213-2414

Usually, diphteria toxin concentration and purification is performed after detoxification due to its high danger. In this work, an alternative diphteria toxoid (DTx) concentration and purification method by affinity chromatography is proposed. Screening of 19 triazinic dyes for selecting the best ligand for DTx concentration and purification by affinity chromatography was performed. Cibacron Blue 3GA and Reactive Green 10 showed the highest affinity for DTx. The adsorption isotherms of DTx on Cibacron Blue 3GA-Sepharose and Reactive Green 19-Sepharose, showed a good fit of experimental data to a Langmuir-type isotherm and allowed the calculation of a maximum capacity (qm) of 1.21 ± 0.12 μmol DTx/mL matrix and 1.44 ± 0.14 μmol DTx/mL matrix respectively and a dissociation constant (Kd) of 9.75 ± 2.90 μM and 1.58 ± 0.38 μM respectively. Blue R-HE-Sepharose isotherm did not show a good fit of experimental data to a Langmuir-type isotherm due to its high Kd. Cibacron Blue 3GA and Reactive Green 10 are promising ligands for concentration and purification of DTx by affinity chromatography.