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The major goal of this investigation was to prepare carvedilol nanocrystals (CRL-NCs) for better solubility, stability, and bioavailability. Using polyvinyl pyrolidine K-30 (PVP) and sodium dodecyl sulphate (SDS) as stabilisers, CRL-NCs were effectively synthesised by emulsion-diffusion, followed by the high-pressure homogenization (HPH) method. The AL classes of phase solubility curves with ideal complexes produced with stabilisers were estimated by thermodynamic parameters. The docking study was performed with the active site of a β-1 adrenoreceptor protein, and the CRLs docking score was revealed as −23.481 Kcal/mol−1. At 25 and 37 °C, the optimum interaction constant was determined for PVP (144 and 176 M−1) and SDS (102 and 121 M−1). The average particle size (PS) of the produced stable CRL-NCs is 58 nm, with a zeta potential of −27.2 ± 2.29 mV, a poly dispersibility index of 0.181 ± 0.012, a percentage yield of 78.7 ± 3.41, drug content of 96.81 ± 3.64%, and entrapment efficiency of 83.61 ± 1.80%. The morphological data also reveals that the CRL-NCs were nearly sphere shaped, with distinct and smooth surfaces. CRL-NCs were studied using X-ray diffraction (XRD), fourier transform infrared (FT-IR) spectroscopy, and differential scanning calorimetry (DSC), and the results show no chemical structural alterations, even when PS was reduced. NCs accelerate their in vitro dissolution release rate by about three times faster than CRL-MCs (microcrystals). When kept at 4 °C, the CRL-NCs exhibit good physical stability for six months. As a result, the CRL-NCs created via emulsion-diffusion followed by HPH with stabilisers can be used to increase the solubility, stability, and bioavailability of poorly soluble or lipophilic drugs.

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The present work aimed to develop a chronotherapeutic system of valsartan (VS) using nanocrystal formulation to improve dissolution. VS nanocrystals (VS-NC) were fabricated using modified anti-solvent precipitation by employing a Box–Behnken design to optimize various process variables. Based on the desirability approach, a formulation containing 2.5% poloxamer, a freezing temperature of −25 °C, and 24 h of freeze-drying time can fulfill the optimized formulation’s requirements to result in a particle size of 219.68 nm, 0.201 polydispersity index, and zeta potential of −38.26 mV. Optimized VS-NC formulation was compressed (VNM) and coated subsequently with ethyl cellulose and HPMC E 5. At the same time, fast dissolving tablets of VS were designed, and the best formulation was loaded with VNM into a capsule size 1 (average fill weight—400–500 mg, lock length—19.30 mm, external diameter: Cap—6.91 mm; Body—6.63 mm). The final tab in cap (tablet-in-capsule) system was studied for in vitro dissolution profile to confirm the chronotherapeutic release of VS. As required, a bi-pulse release of VS was identified with a lag time of 5 h. The accelerated stability studies confirmed no significant changes in the dissolution profiles of the tab in cap system (f2 similarity profile: >90). To conclude, the tab in cap system was successfully developed to induce a dual pulsatile release, which will ensure bedtime dosing with release after a lag-time to match with early morning circadian spikes.

With the recent advances of nanotechnology, dendrimers are emerging as a highly attractive class of drug delivery vectors for cancer therapy. Dendrimers are multifunctional smart Nanocarriers to deliver one or more therapeutic agent safely and selectively to cancer cells. The high level of control over the synthesis of dendritic architecture makes dendrimers a nearly perfect (spherical) nanocarrier for site-specific drug delivery. The presence of functional groups in the dendrimers exterior also permits the addition of other moieties that can actively target certain diseases which are now widely used as tumor targeting strategies. Drug encapsulation, solubilization and passive targeting also equally contribute to the therapeutic use of dendrimers. Dendrimers are ideal carrier vehicles on cytotoxicity, blood plasma retention time, biodistribution and tumor uptake. In this review we highlight the advantages of dendrimers over conventional chemotherapy, toxicity and its management, following anti-cancer drugs delivered by using dendrimers and recent advances in drug delivery by various types of dendrimers as well as its diagnostic applications.