Partially selective semiconductor redox electrodes.

Redox electrodes made of passivated metals of the subgroups IV to VI of the periodic system with a surface coating of n-conducting metal oxides, generated by oxidizing agents or anodic oxidation, are well suited for measuring the concentration of oxidizing agents. Neither oxygen nor reducing agents affect the measurements. There is a correlation between the mean conductivity of the passive layer and its selectivity.

[The adaptation of four protein determination methods to flow injection analysis (FIA)].

The adaptation of 4 manual methods to the flow-injection analysis is described for the determination of proteins (Biuret- and Exton-method, albumin and hemoglobin determination). The comparison of analytical results of FIA with the manual methods shows a very good agreement of values. Flow-injection-analysis appears not only as an excellent possibility to automate these 4 investigated methods but it also shows unlike the manual methods a considerable better precision and accuracy of the analytical results and a reduction of time and materials.