Effect of Viscosity and Density of Substance on Dielectric Properties of Medicinal Compounds in Solution

Complex permittivity in terms of dielectric constant (ε') and dielectric loss (ε") of medicinal compound paracetamol in dimethyl sulfoxide (DMSO) solvent was determined with different weight fractions at microwave frequency 9.85 GHz at constant temperature 27 ℃. The information on dielectric properties is related to the properties of the substance for preparation of granules while making dosage forms like tablets and capsules. Refractive index (nD), dielectricconstant (ε') and dielectric loss (ε") were used for the measurement of relaxation time (τ). The viscosity (η) and density of paracetamol in DMSO were determined using a conventional Ostwald's viscometer and specific gravity bottle respectively. The aim of the present work was to study the dielectric properties of the drugs and attempted to determine their correlations with density and viscosity to understand the behavior of the dielectric properties under different conditions like a concentration in solution. It was observed that there was a strong correlation of dielectric properties like dielectric constant, dielectric loss and dielectric relaxation time with viscosity and density. The absolute values of correlation coefficient (R) were in the range of 0.946 to 0.987 for paracetamol-DMSO system, indicating a strong correlation.