Determination of total proteins in several tissues of rat a comparative study among spectrophotometric mehods

摘要

In the present paper,five spectrophotoetric mehods-biuret,Lowry modified by Hartree (Lowry/Hartree),p-chloranil,ultraviolet at 280 nm (UV-280 nm),and ultraviolet at 260/280 nm)-were used for protein determination in several rat tissues and the results were compared.The lowry/Harttee method showed the highest sensitivity(0.9 #mu#g/ml) and the biuret method the lowest sensitivity(55.7 #mu#g/ml).Theresults were not statistically different for the following mehtods and tissues:Lowry/Hartree was compared to biuret for five tissues (adrenal,spleen,whole brain,liver and small intestine),to p-chloranil for two tissues (liver and epilidymal fat pad),and to UV-260/280 nm for three tissues (whol brain,liver and pancreas).Since the Lowry/Hartree method needs a larger period of time for a whole assay to be carried out,we recommend for determination of total protein the following methods:UV-260/280 nm for whole brain,liver,and pancreas,p-chloranil for epilidymal fat pad,and biuret for other tissues.We do not recommend the UV-280 nm method because there are many interfering substances inthe tissues.