Vol 14, No 2 (2024)

Solubility is a critical factor for the therapeutic action of drugs and does not depend on the administration of routes. Various conventional methods are used to enhance the solubility of the drug, which show limited applicability. Nanotechnology is used to improve the solubility and bioavailability of drugs that belong to BCS classes II and IV. Nanosuspension is the dispersion of pure drug nanoparticles in aqueous with a minimum amount of surfactant, stabilizing the formula-tion. Various techniques, such as the bottom-up approach, dissocubes, nanopure, nanoedge, nano-jet process, supercritical fluid, dry co-grinding, milling media, and nanoprecipitation, have been used to formulate nanosuspension. Nanosuspension can be administered orally, inhalation, trans-dermal, ocular, injectable, topical, and pulmonary. To resolve the problem of solubility and stabil-ity, nanosuspension has received much attention because of its technical simplicity, cost-effectiveness, and ease of significant scale-up. Nanosuspension can control particle size surface charge properties and release the drug at specific sites at an optimal rate. Recently, more than 100 patents have been published on nanosuspension. This review article covers the different prepara-tion methods, formulation composition, marketed products, characterization, and recent patents on nanosuspension. The various benefits and evaluation of the parameters of nanosuspension are discussed briefly. This patent-based review will enhance the knowledge of control drug delivery and related patents on nanosuspension.

Background::The tumour microenvironment (TME) affects tumour development in a crucial way. Infinite stromal cells and extracellular matrices located in the tumour form complex tissues. The mature TME of epithelial-derived tumours exhibits common features irrespective of the tumour's anatomical locale. TME cells are subjected to hypoxia, oxidative stress, and acidosis, eliciting an extrinsic extracellular matrix (ECM) adjustment initiating responses by neighbouring stromal and immune cells (triggering angiogenesis and metastasis).

Objective::This report delivers challenges associated with targeting the TME for therapeutic pur-poses, technological advancement attempts to enhance understanding of the TME, and debate on strategies for intervening in the pro-tumour microenvironment to boost curative benefits.

Conclusion::Therapeutic targeting of TME has begun as an encouraging approach for cancer treatment owing to its imperative role in regulating tumour progression and modulating treatment response.

Objective:The present study proposed Dabigatran Etexilate loaded solid supersaturat-ed self-nanoemulsifying drug delivery system (solid S-SNEDDS) for enhancement of payload, drug solubility, dissolution rate as well as minimization of drug precipitation.

Methods:The study involved formulation optimization using the Box-Behnken design. The op-timal SNEDDS consisting of Caprylic acid (32.9% w/w), Cremophor EL (50.2% w/w) and Transcutol HP (18.8% w/w) as Oil, Surfactant and Co-surfactant, respectively were formulated and evaluated for particle size, PDI, Zeta potential and saturation solubility. The SNEDDS was further incorporated with PPIs for the preparation of supersaturated SNEDDS (S-SNEDDS) to in-crease the drug payload in the formulation. S-SNEDDS was converted to solid S-SNEDDS by ad-sorption onto the porous carrier i.e., Aerosil®200. The in-vitro drug release study was also con-ducted for solid S-SNEDDS.

Results:SNEDDS had size, PDI, and Zeta potential of 82 nm, 0.347, -10.50 mV, respectively. SNEDDS enhanced the saturation solubility of the drug by 93.65-fold. Among PPIs, HPMC K4M showed the most effective response for the formulation of S-SNEDDS. The S-SNEDDS had a more substantial drug payload, which further increased the solubility by 150 times of pure drugs and 16 times of SNEDDS. Solid S-SNEDDS exhibited free-flowing properties. Reconstituted sol-id S-SNEDDS had acceptable size, PDI, and Zeta potential of 131.3 nm, 0.457, and -11.3 mV, respectively. In-vitro drug release study revealed higher drug dissolution and minimized drug pre-cipitation by SNEDDS compared to marketed products and pure drugs.

Conclusion:Proposed nano-formulation was found to efficiently improve the aqueous solubility of the drug and avoid the drug precipitation, thereby avoiding drug loss and improving drug bioa-vailability.