P-Diazobenzene sulfonic acid

Only few applications have been reported to determine antioxidants in rubbers or polymers by using electrochemical methods [927,928]. Sawada et al. [929] reported successful separations by coupling the antioxidants with p-diazobenzene sulfonic acid before electrophoresis. Amine AOs were coupled in acetic acid and phenolic AOs in NaOH-ethanol were analysed by CE methods. MEKC separation of the four major food grade antioxidants (PG, BHA, BHT, TBHQ) was completed within 6 min with pmole amount detection using UV absorption [930]. RPLC was not as efficient and required larger sample amounts and longer separation times. 

The inference that the oxidase(s) is an ectoenzyme has been made from a variety of data. The demonstration that PMNs possess both the Cu/Zn and the Mn superoxide dismutase prompted the suggestion that O must be formed at a site which protected it from the action of these enzymes. Since O appeared in the fluid surrounding the PMN, the most advantageous site appeared to be the plasma membrane. In accord with this proposal, treatment of PMNs with a nonpenetrating organic anion, p-diazobenzene sulfonic acid, in association with cytochalasin B to prevent internalization of membrane into a phagocytic vacuole, inhibited the... 

The polaragraphic analysis of NMe was studied in buffered solns. The half wave potential was found to vary with pH hence the necessity of using a buffered scln (Ref 22). Gas CjirGiTiatGg retention times for NMe at 50-90° and 110— 50° are listed in Ref 38, various supports and stationary phases were used. Small amts were quanty detd by coupling with p-diazobenzene-sulfonic acid and detg the colored prod spec-trophotometrically (Ref 37)... 

---