Ashwini Deshpande

Co-crystals consists of API and a stoichiometric amount of a pharmaceutically acceptable co-crystal former. Pharmaceutical Co-crystals are nonionic supramolecular complexes and can be used to address physical property issues such as solubility, stability and bioavailability in pharmaceutical development without changing the chemical composition of the API. Maximum of the drugs belong to BCS class II, means these are drugs which have low solubility and high permeability. There are various methods of solubility enhancement such as salt formation, solvates, polymorphs, complexation, co-crystallization, etc. Co-crystallization mainly consists of two components the API and the coformer. Thse coformer is the one which acts as a main component for solubility enhancement. In case of ionization or salt formation there is a drawback as compared to co-crystallization. In case, of salt formation or ionization presence of an ionic center is required. This is not a requirement in case of co-crystallization.FDA has approved such combination called Juvisync1 (Sitagliptin and Simvastatin) in 2011.Glipizide belongs to the anti-diabetic class of drug and Rosuvastatin calcium is a cholesterol reducing agent. As both these drugs are class II drug, solubility issues has to be solved. As Glipizide was available not in its salt form, its co-crystallization was decided to do. Hence, co-crystallization method was selected as the method to enhance the solubility. The co-crystals were characterized and showed the conformance of the presence of both the APIs.

Cyclodextrin nanosponges are solid, porous, bio-compatible, nano-particulate three dimensional structures which form inclusion complexes with different types of lipophilic or hydrophilic drug molecules and have been used as drug carrier for different drugs. In this present work, new cyclodextrin-based nanosponges of atorvastatin were prepared by condensation polymerization and interfacial polymerization to release Atorvastatin in expected manner in the treatment of dyslipidaemia as novel carriers. Results of encapsulation efficiencies of all formulation trials revealed that condensation polymerization is the best method for nanosponges formation and that is considered as best selected method for preparation. For the selected condensation polymerization, encapsulation efficiencies of atorvastatin in nanosponge formulations were found to be 72 to 86%. SEM images revealed their porous nature and cavity was of β-cyclodextrin. The mean particle size of nanosponges was about 328 nm and Zeta potentials of the nanosponges were sufficient enough (-10 to -15mv) due to presence of carboxylic group and inclusion complex formation which assured stability of formulations. The results of FTIR and DSC confirmed that atorvastatin was compatible with β-cyclodextrin and completely encapsulated in nanosponges structure respectively. The selected formulation produces good dissolution profile (release more than 75% atorvastatin within 60 mins in 0.1 N HCL) which indicated that the solubility of atorvastatin was improved by forming nanosponges. In accelerated stability studies, no significant changes occurred in physical appearance and drug content of atorvastatin nanopsonges formulation during 3 months stability studies. Atorvastatin nanosponges confirmed by insolubility in water and organic solvents like dimethyl formamide, dichloromethane.