BIOCHEMISTRY - Main Regulators and Biological Fluids of the Human Body - 2016

2. HORMONES

2.12. Practical Part. Study of Qualitative Reactions for Hormones

2.12.1. Qualitative Reactions for Protein-Peptide Hormones

Insulin (a hormone produced by the $\beta$-Cells of the islets of Langerhans in the Pancreas) regulates Blood glucose levels, is widely used in the Treatment of Diabetes Mellitus in humans, and exhibits an anabolic effect.

This hormone yields almost all characteristic Color Reactions for Proteins. For qualitative reactions, pharmaceutical insulin in ampoules is used, taking 5 drops for each reaction.

Experiment 1. Biuret test

Perform the biuret test, record your observations, and draw an appropriate Conclusion (see Part 1 of this manual, Subsection 1.8, Experiment 1).

Experiment 2. Ninhydrin test

Perform the ninhydrin test, record your observations, and draw an appropriate conclusion (see Part 1 of this manual, Subsection 1.8, Experiment 2).

Experiment 3. Xanthoproteic test

Perform the xanthoproteic test, record your observations, and draw an appropriate conclusion (see Part 1 of this manual, Subsection 1.8, Experiment 3).



Last update: 06/08/2026

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