1. A method is described for the colorimetric determination of peroxidase with N,N-dimethyl-p-phenylenediamine. The amount of red pigment formed by peroxidase is proportional to the concentration of enzyme and to the time of incubation during the first 40 to 90 seconds. The influence of the concentration of enzyme, N,N-dimethyl-p-phenylenediamine, H(2)O(2), the time of incubation, pH, the tempe...

A bioassay of 4-chloro-m-phenylenediamine for possible carcinogenicity was conducted using Fischer 344 rats and B6C3F1 mice. 4-Chloro-m-phenylenediamine was administered in the feed, at either of two concentrations, to groups of 49 or 50 male and 50 female animals of each species. The dietary concentrations of 4-chloro-m-phenylediamine used in the chronic bioassay for low and high dose rats wer...

In this work, a sensitive dual mode competitive electrochemical immunosensor based on differential pulse voltammetry (DPV) and square wave (SWV) response modes for quantitative determination of dibutyl phthalate (DBP) was successfully established. According to diethylenetriamine (DETA) assisted hydrothermal strategy, novel N-doped graphene/CoSe2 nanobelt composite prepared. Afterwards, PEI func...

showed no respiration due to endogenous substrates. Only L-ascorbate with NNN‘N’tetramethyl-p-phenylenediamine was oxidized by membrane particles and the specific activity obtained was lower than in corresponding particles prepared from NH4+-grown cells. Low-temperature reduced-minus-oxidized difference spectra (Fig. 1, trace b) suggested that this lack of electron-transport activity may be due...

Lactobacillus sanfrancisco LTH 2581 can use only glucose and maltose as sources of metabolic energy. In maltose-metabolizing cells of L. sanfrancisco, approximately half of the internally generated glucose appears in the medium. The mechanisms of maltose (and glucose) uptake and glucose excretion have been investigated in cells and in membrane vesicles of L. sanfrancisco in which beef heart cyt...

A series of metal-containing epoxy polymers have been synthesized by the condensation of epichlorohydrin (1-chloro-2,3-epoxy propane) with Schiff base metal complexes in alkaline medium. Schiff base was initially prepared by the reaction of 2,6 dihydroxy 1-napthaldehyde and o-phenylenediamine in 1 : 2 molar ratio and then with metal acetate. All the synthesized compounds were characterized by e...

Aromatic bis-aldehydes have been used as building blocks in the synthesis of polyazomethines (a class of conjugated Schiff bases) and their physicochemical properties have been studied. Six dialdehydes have been synthesized, 3a-3f, via etherification reaction between aromatic diols (2a-2f) and 4-fluorobenzaldehyde (1) (see Scheme 1), and then polymerized with 1,4-phenylenediamine (4a) and 4,4'-...

We report a Cu-catalyzed coupling between triarylaluminum reagents and alkyl halides to form arylalkanes. The reaction proceeds in the presence of N,N,N',N'-tetramethyl-o-phenylenediamine (NN-1) as a ligand in combination with CuI as a catalyst. This catalyst system enables the coupling of primary alkyl iodides and bromides with electron-neutral and electron-rich triarylaluminum reagents and af...