Thiolated Chitosan-Centella asiatica Nanocomposite: A Potential Brain Targeting Strategy Through Nasal Route.

The major challenge associated with the treatment of neurological disorders is the inefficiency of drugs to enter the Central Nervous System (CNS). Polymer-drug conjugates are now being tailored to overcome this hindrance associated with conventional drugs. The study aimed at developing polymer hybrid nasal nanocomposite for enhanced delivery of Centella to the CNS. Thiolated chitosan was complexed with Centella to form a composite using EDAC hydrochloride. The composite was characterized by FTIR, XRD, NMR, and MS. Further, this composite was converted into a nanoformulation by the ionic-gelation method, characterized, and subjected to ex vivo permeation studies. Additionally, MTT assay was performed using Human Uumbilical cord Vein Endothelial Cells (HUVECs) mimicking Blood-Brain Barrier (BBB) to establish the safety of nanocomposite. The targeting efficacy was predicted by molecular docking studies against receptors associated with BBB. The FTIR, XRD, NMR, and MS studies confirmed the chemical conjugation of thiolated chitosan with Centella. Nanocomposite characterization through SEM, AFM, and DLS confirmed the size and stability of the developed nanocomposite having a zeta potential of - 14.5 mV and PDI of 0.260. The nanocomposite showed no signs of nasal ciliotoxicity and good permeation of 89.44 ± 1.75% (mean ± SD, n = 3) at 8 h across the nasal mucosa. MTT assay showed that the nanocomposite had lesser toxicity compared to the free drug (IC50 of Centella-269.1 µg/mL and IC50 of CTC nanocomposite-485.375 µg/mL). The affinity of polymer to the BBB receptors as proved by docking studies suggests the ability of polymer-based nanocomposite to concentrate in the brain post nasal administration.

Thiolated polymer nanocarrier reinforced with glycyrrhetinic acid for targeted delivery of 5-fluorouracil in hepatocellular carcinoma.

The present work investigates the targeting efficacy of a novel thiolated polymer-based nanocomposite reinforced with glycyrrhetinic acid (GA) and loaded with 5-fluorouracil in hepatocellular carcinoma (HCC). The thiolated polymers were synthesized by EDAC-mediated conjugation reactions and lyophilization. The nanoparticles were prepared by solvent diffusion and high-pressure homogenization method. The prepared nanocomposite was characterized by Fourier transform infrared (FTIR) radiation, x-ray diffraction (XRD), dynamic light scattering (DLS), scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques. Pharmacological evaluation of the formulation was carried out on a rat model of diethylnitrosamine (DEN), and carbon tetrachloride (CCl4)-induced HCC and MTT assay was carried out with HEP-G2 cell line. In silico studies were conducted to investigate the probable mechanistic pathway of the nanocomposite. FTIR and XRD analysis indicated the successful thiolation of the polymers and confirmed the formation of the nanocomposite without any incompatibilities. DLS, SEM/EDX and AFM characterization confirmed that the nanoparticles were within the nano-size range. MTT assay implied the cytotoxic nature of the nanocomposite against hepatic carcinoma cells. The in vivo study revealed that serum SGOT, SGPT, ALP, GGT and total bilirubin levels were significantly reduced, in comparison with disease control and the result was confirmed by histopathology studies. The results of the HPLC analysis of liver homogenate confirmed the liver targeting ability of the nanocomposite. In silico studies exhibited significant binding affinity of GA and thiolated Eudragit towards liver homolog receptor-1 (LRH-1) suggesting that the developed nanocomposite could be a potential material for the treatment of HCC.

Improved treatment efficacy of risedronate functionalized chitosan nanoparticles in osteoporosis: formulation development, in vivo, and molecular modelling studies.

Delivery of bisphosphonates-like risedronate has been a major challenge till date due to its poor bioavailability and gastrointestinal tract adverse effects. In this study, we explored the prospective use of risedronate functionalised chitosan nanoparticle (RISCN) for management and treatment of osteoporosis. The prepared nanoparticle was characterised by using scanning electron microscopy, atomic force microscopy, and dynamic light scattering technique. Osteoporosis was induced on quarantined female Wistar rats and treated with RISCN. Docking studies were performed to establish the molecular mechanism of RISCN in improving the bone microarchitecture. Results indicated that there was a significant improvement in bone mineral density and healing of trabecular microarchitecture with less cortical porosity on the bone surfaces of the treatment groups. Docking studies indicated a high affinity and binding of chitosan and RISCN towards the human farnesyl diphosphate synthase (FDPS). Thus, a novel risedronate-loaded chitosan nanoparticle revealed promising results in an effective bone bridging process and osteoporosis treatment.