A SEMIAUTOMATED DIGESTION METHOD FOR TOTAL NITROGEN IN PLANT MATERIALS

A method for determining total nitrogen in Kjeldahl digestion solution using a centrifugal analyser

Correspondence: A method for determining total nitrogen...

The digestion method using a small proportion of a strong oxidizing agent perchloric acid seems to have been taken from a ’continuous flow method’, which was not designed for discrete digestion and analysis. There is considerable evidence that satisfactory digestion ofeven tMrly refractory substances can be achieved without the use of perchloric acid (1) and it is now usually recommended that p...

Determination of total nitrogen in aqueous samples using persulfate digestion

Determination of total nitrogen in aqueous samples after potassium persulfate digestion compared favorably in both precision and nitrogen recovery with determinations obtained using Kjeldahl digestion. The determination of total nitrogen (TN = inorganic and organic fixed nitrogen) has largely depended either on acid Kjeldahl digestion ( cf. Strickland and Parsons 1972) or on photo-oxidation (Ar...

Semiautomated spectrophotometry of total phospholipids in plasma.

A one-stage semiautomated method for estimating total phospholipids in plasma is reported. The phospholipids are extracted into aqueous ethanol, combined with a Lewis acid, and the change in pH is monitored colorimetrically. The method, compared with the acid digestion method of Gomori [J. Lab. Clin. Med. 27, 955 (1942)], gives results that are about 0.25 mmol/liter lower, but seems to be a sui...

Semiautomated method for quantitative urine culture.

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