The Solubility and Complexing Properties of Oxytetracycline and Tetracycline III

The present study extends the investigation of complexing tendencies of oxytetracycline to (a) a series of isomer, multifunctional aromatic compounds, (b) certain biochemicals, (c) calcium and magnesium ions, both free and as chelates, and (d) hexametaphosphate. The relative importance of grouping and their location on the binding tendency has been demonstrated. Measurements carried out on purines, DNA, B vitamins, etc., show that such biochemicals are, in general, relatively strong complexing agents. Data on alkali earths suggest that complexed drugs may still undergo chelation. Hexametaphosphate appears to undergo very slight, if any, complexing reaction with either tetracycline or oxytetracycline at pH values between 5 and 8.