WebJun 23, 2009 · The enthalpies of solution $$ \\Updelta_{sol}^{{}} H_{m}^{{}} $$ of polymorphic forms I and II of theophylline in water at 298.15 K using the isoperibol solution calorimeter have been determined in the range of concentration (0.311–1.547) · 10−3 /mol · kg−1. The enthalpies of hydration $$ \\Updelta_{hyd}^{{}} H_{m}^{o} $$ were determined … WebFeb 27, 2024 · Theophylline is a methylxanthine alkaloid that is a competitive inhibitor of phosphodiesterase (PDE; Ki = 100 μM). It is also a non-selective antagonist of adenosine A receptors (Ki = 14 μM for A1 and A2). Theophylline induces relaxation of feline bronchiole smooth muscle precontracted with acetylcholine (EC40 = 117 μM; EC80 = 208 μM).

Solubility of theophylline in aqueous N,N ... - ScienceDirect

WebTheophylline is a cyclic phosphodiesterase inhibitor. It antagonizes Adenosine A Receptors and weakly inhibits alkaline phosphodiesterases and 5′-nucleotidase. ... Soluble in water (8.3 g/l) at 20° C, 0.1 M NaOH, 0.1 M HCl, ethanol (moderately), DMSO, alkali hydroxides, ammonia, dilute hyrochloric acid, nitric acid, ... WebDimensional changes, gel layer evolution and drug release studies in hydrophilic matrices loaded with drugs of different solubility K Avgoustakis 2007, International Journal of Pharmaceutics irish banks going cashless

Solubility of caffeine in water, ethyl acetate, ethanol, carbon ...

WebCommon-Ion Effect. The common-ion effect is a term that describes the decrease in solubility of an ionic compound when a salt that contains an ion that already exists in the chemical equilibrium is added to the mixture. This effect best be explained by Le Chatelier's principle.Imagine if the slightly soluble ionic compound calcium sulfate, CaSO 4, is added … WebJan 1, 1975 · Melting Range The original synthetic literature27 reported a melting point 0 ; 264O for theophylline subsequently the melting range has been reported to be between 271° and 274O C.28 c Solubility The reported solubility of theophylline is 8.3 mg/ml in water; 12.5 mg/ml in ethanol; 11.f,Tg/ml in , Several chloroform; and sparingly soluble in ... WebThe solubility of theophylline – oxalic acid co-crystal and theophylline – glutaric acid co-crystal was determined in 4:1 chlroform – methanol and in pure chloroform respectively. At equilibrium with the solid theophylline – oxalic acid co-crystal, the theophylline concentration is only 60 % of the corresponding value for the porsche macan palm springs