Formulation Optimization and Biopharmaceutical Evaluation of Imatinib Mesylate Loaded ß-cyclodextrin Nanosponges.

BACKGROUND: Many researchers have prepared and evaluated nanosponges and claimed their advantages as an effective drug carrier, especially it was observed prominently in case of anti-fungal drugs. The materials employed to synthesize nanosponges were mainly crosslinking agents, different beta-cyclodextrin and other cellulose-based polymers. Many of them had used ratio proportions of cross-linking agents, d polymers to synthesize these nanosponges which ultimately produce a porous mesh-like network known as nanosponges where actually drug is encapsulated or loaded. OBJECTIVE: In the present investigation, we observed the effect of various levels of crosslinking agents and beta-cyclodextrin concentrations on porosity, drug encapsulation, zeta potential and drug release by employing the quality by design approach to synthesize nanosponges rather than merely keeping both concentrations in proportions. METHODS: We have slightly modified the method reported earlier i.e. melting method in which we have used rota evaporator receiver vessel for melting cross-linking agent and beta- cyclodextrin, rotated at 20 RPM at 100°C. RESULTS: In a quality by design approach, we observed that out of four dependent variables i.e. porosity, drug loading, zeta potential and drug release, three significantly depend on the crosslinking of beta-cyclodextrin molecules which is highly appreciated by the amount of cross-linking agent present in the reaction. The pharmacokinetics of Imatinib loaded optimized nanosponges were compared with the reference product to observe the pattern of absorption and disposition. CONCLUSION: Nanosponges synthesized by optimization technique could be effective means of anti-cancer drug oral administration as they encapsulate the drug effectively and offer a prolonged release of drug which gradually releases the drug and avoids unnecessary exposure of the drug.

Extended release delivery of erlotinib glutathione nanosponge for targeting lung cancer.

Systemic and uncontrolled administration of erlotinib hydrochloride (ETB) is associated with severe toxicity. A novel targeted and extended release nanosponge (NS) was synthesized from glutathione (GHS) by a one-step reaction between ß-cyclodextrin and pyromellitic dianhydride at room temperature for delivery of ETB in lung cancer. Characterization studies were performed using sophisticated instruments. In-vitro release study was performed in the presence of incremental concentrations of GHS which was analyzed using HPLC. Cell cytotoxicity study was evaluated on human lung cancer (A549) cell lines. In-vivo tumour inhibition and biodistribution of ETB-loaded GHS-NS (ETB-NS) were performed on BALB/c mice. NS obtained was spherical, size 212 ± 2.45 nm and high drug entrapment (92.34 ± 5.31%) (p < .001). In-vitro extended drug release (76.89 ± 0.1% release at 168 h), which was directly proportional to the concentration of GHS, demonstrated tumour targeting. There was enhanced in-vitro cytotoxicity and 97.5% inhibition in tumour growth on administering NS when compared to plain ETB (48% inhibition) indicating targeting of NS to the tumour site. Biodistribution study and in-vivo tumour growth inhibition study revealed drug release to the cancerous cell, thus preventing unnecessary drug exposure. ETB-NS exhibits extended drug release proportional to the external GSH concentration.

Enhancement of oral bioavailability of anti-HIV drug rilpivirine HCl through nanosponge formulation.

OBJECTIVE: To synthesize ß cyclodextrin nanosponges using a novel and efficient microwave mediated method for enhancing bioavailability of Rilpivirine HCl (RLP). SIGNIFICANCE: Belonging to BCS class II RLP has pH dependent solubility and poor oral bioavailability. However, a fatty meal enhances its absorption hence the therapy indicates that the dosage form be consumed with a meal. But then it becomes tedious and inconvenient to continue the therapy for years with having to face the associated gastric side effects such as nausea. METHOD: Microwave synthesizer was used to mediate the poly-condensation reaction between ß-cyclodextrin and cross-linker diphenylcarbonate. Critical parameters selected were polymer to cross-linker ratio, Watt power, reaction time and solvent volume. Characterization studies were performed using FTIR, DSC, SEM, 1H-NMR and PXRD. Molecular modeling was applied to confirm the possibility of drug entrapment. In vitro drug dissolution followed by oral bioavailability studies was performed in Sprawley rats. Samples were analyzed using HPLC. RESULTS: Microwave synthesis yields para-crystalline, porous nanosponges (∼205 nm). Drug entrapment led to enhancement of solubility and a two-fold increase in drug dissolution (P < 0.001) following Higuchi release model. Enhanced oral bioavailability was observed in fasted Sprawley rats where Cmax and AUC0-∞ increases significantly (Cmax of NS∼ 586 ± 5.91 ng/mL; plain RLP ∼310 ± 5. 74 ng/mL). CONCLUSION: The approach offers a comfortable dosing zone for AIDs patients, negating the requirement of consuming the formulation in a fed state due to enhancement in drugs' oral bioavailability.