In this work we describe a detailed treatment of polarographic data curves, including error analysis, by means of nonlinear least-squares in its standard form (or resorting to the errors in variables model). Error estimates for the related parameters are additionally verified by Monte-Carlo simulation and resampling techniques.

The polarographic behaviour of formaldehyde (FA) was studied using cyclic and square wave polarography (SWP) methods. FA was derivatized with 2.4-dinitrophenylhydrazine (DNPH). The influence of several variables (including nature of the buffer, pH, concentration, scan rate, drop size, etc.) was examined in SWP method for FA. The best SWP responses were obtained in acetate buffer pH 5.0. The pea...

1. A polarographic method of measuring and continuously recording the concentration of oxygen in solution down to the order of 1O-9M has been described. 2. This method has been used to determine the respiration rate of bacteria as a function of oxygen concentration. 3. The results so obtained have shown that the respiration rate of bacteria is related to the oxygen concentration by the Michaeli...

We describe the measurement of lipase (triacylglycerol lipase; EC 3.1.1.3) in serum by continuous monitoring of relative rates of oxygen consumption with a polarographic oxygen electrode. The reactions described by Proelss and Wright (Clin. Chem. 23: 522-531, 1977) are used: trilinolein, with lipase catalysis, yields linoleic acid, which reacts with oxygen in the presence of lipoxygenase. Lipas...

Bovine and dogfish (Squalus acanthias) heart submitochondrial particles and cytochrome c oxidase (EC 1.9.3.1) were prepared. Biphasic Eadie--Hofstee plots from steady-state polarographic assays were obtained for both species. Phospholipid analyses indicated that cardiolipin was absent from this active dogfish enzyme.

Photosystem II (PSII) produces dioxygen from water in a four-stepped process, which is driven by four quanta of light and catalysed by a Mn-cluster and tyrosine Z. Oxygen is liberated during one step, coined S(3)=>S(0). Chemical intermediates on the way from reversibly bound water to dioxygen have not yet been tracked, however, a break in the Arrhenius plot of the oxygen-evolving step has been ...