Hemoglobin is the major protein component of red blood cell and as an allosteric tetrameric protein; it has an important role in carrying oxygen from lungs to different tissues, and it reacts with other gasses and also with several organic molecules. Amlodipine, which is calcium channel blocker, used for the treatment of hypertension, angina pectoris and cerebrovascular disease. In recent times, many studies concerning magnetic fields effects on biological objects were carried out, because in modern society, due to its impossibility of avoiding exposure to magnetic field produced by transmission and distribution of electric power and devices used inside houses and work places. In this work, we investigated the interaction between amlodipine and hemoglobin in the absence and presence of magnetic field (52 mT) using UV and fluorescence absorption spectroscopy. To analyze the UV data, obtaining the binding capacity, g, binding constant, K, and Hill constant, nH, Scatchard and Hill equations were employed. The results revealed that the value of g was the same in both case, in the presence and absence of magnetic field, but nH and K decreased slightly in the presence of magnetic field. In the case of fluorescence spectroscopy, the fluorescence intensity was found to be decreased in the presence of magnetic field.

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