12
For example, erythromycin dihydrate shows a more e cient dissolution rate than the respective monohydrate and Theophylline has a low aqueous solubility (8 mg/mL at 25°C) and can exist as an anhydrate or as a monohydrate
The observed Download scientific diagram | Powder dissolution profiles of anhydrous theophylline processed with microcrystalline cellulose (MCC)
Anhydrous theophylline underwent multiple transformations (anhydrate --> hydrate --> anhydrate)
For example, Tantry et al [11] in 2007 found that for theophylline, the anhydrous to hydrated formation is easy but a complete transformation of the hydrate to anhydrous form is practically anhydrous theophylline - sodiu m saccharin di hydrate (TA-NSD) and theophylline monohydrate - sodium saccharin dihydrate (TM-NSD)
How many moles of water of crystallisation are present? Dissolution of 1 mol of the hydrate crystals in water resulted in the absorption of 67 kJ of heat
The melting point and the enthalpy of fusion of each polymorph determined by differential scanning calorimetry (DSC) were 273
On the other hand, monohydrate citric acid contains one water molecule per citric acid molecule