Physicochemical Characterisation of Commercially Available Prussian Blue Insoluble Samples and Its Comparison with Radiogardase Cs

The physicochemical properties of insoluble Prussian blue (PB) play an important role in its thallium binding ability. Therefore, the present study aimed to characterise various physicochemical parameters of PB available commercially and compare them with the USFDA-approved Radiogardase ® -Cs. In addition, PB was synthesised by indirect and direct methods. PB samples and Radiogardase®-Cs were analysed for various parameters like particle size, moisture content, and thermogravimetric analysis (TGA) and correlated with its Maximum Binding Capacity (MBC) for thallium. Radiogardase ® -Cs showed the highest MBC of 238 mg/g for thallium with D 90 of 785 μm and moisture content of 23.24 %. The MBC of other PB samples was found to be significantly lower than Radiogardase ® -Cs which was found to be directly proportional to the moisture content. However, other parameters like particle size, and iron content vary significantly but no correlation was observed with MBC for thallium. This finding suggests that moisture content and MBC are extremely important parameters for optimising the PB to achieve desirable pharmacological efficacy for removing thallium in vivo.