Formulation of cartap hydrochloride crosslinked chitosan tripolyphosphate nanospheres and its characterization

Fabrication and characterization of unique sustain modified chitosan nanoparticles for biomedical applications

Chitosan (CS) is a biopolymer that offers a wide range in biomedical applications due to its biocompatibility, biodegradability, low toxicity and antimicrobial activity. Syringaldehyde (1) is a naturally occurring organic compound characterized by its use in multiple fields such as pharmaceuticals, food, cosmetics, textiles and biological applications. Herein, development of chitosan derivative with physicochemical and anticancer properties via Schiff base formation from the reaction of chitosan with sustainable eco-friendly syringaldehyde yielded the (CS-1) derivative. Moreover, in the presence of polyethylene glycol diglycidyl ether (PEGDGE) or sodium tripolyphosphate (TPP) as crosslinkers gave chitosan derivatives (CS-2) and (CS-3NPs) respectively. The chemical structures of the new chitosan derivatives were confirmed using different tools. (CS-3NPs) nanoparticle showed improvement in crystallinity, and (CS-2) derivative revealed the highest thermal stability compared to virgin chitosan. The cytotoxicity activity of chitosan and its derivatives were evaluated against HeLa (human cervical carcinoma) and HEp-2 (Human Larynx carcinoma) cell lines. The highest cytotoxicity activity was exhibited by (CS-3NPs) compared to virgin chitosan against HeLa cell growth inhibition and apoptosis of 90.38 ± 1.46% and 30.3% respectively and IC50 of 108.01 ± 3.94 µg/ml. From the above results, it can be concluded that chitosan nanoparticle (CS-3NPs) has good therapeutic value as a potential antitumor agent against the HeLa cancer cell line.

Fabrication of 3D chitosan/polyvinyl alcohol/brushite nanofibrous scaffold for bone tissue engineering by electrospinning using a novel falling film collector

Despite its advantages, electrospinning has limited effectiveness in 3D scaffolding due to the high density of fibers it produces. In this research, a novel electrospinning collector was developed to overcome this constraint. An aqueous suspension containing chitosan/polyvinyl alcohol nanofibers was prepared employing a unique falling film collector. Suspension molding by freeze-drying resulted in a 3D nanofibrous scaffold (3D-NF). The mineralized scaffold was obtained by brushite deposition on 3D-NF using wet chemical mineralization by new sodium tripolyphosphate and calcium chloride dihydrate precursors. The 3D-NF was optimized and compared with the conventional electrospun 2D nanofibrous scaffold (2D-NF) and the 3D freeze-dried scaffold (3D-FD). Both minor fibrous and major freeze-dried pore shapes were present in 3D-NFs with sizes of 16.11-24.32 μm and 97.64-234.41 μm, respectively. The scaffolds' porosity increased by 53 % to 73 % compared to 2D-NFs. Besides thermal stability, mineralization improved the 3D-NF's ultimate strength and elastic modulus by 2.2 and 4.7 times, respectively. In vitro cell studies using rat bone marrow mesenchymal cells confirmed cell infiltration up to 290 μm and scaffold biocompatibility. The 3D-NFs given nanofibers and brushite inclusion exhibited considerable osteoinductivity. Therefore, falling film collectors can potentially be applied to prepare 3D-NFs from electrospinning without post-processing.

Evaluation of methotrexate encapsulated polymeric nanocarrier for breast cancer treatment

Herein, Methotrexate-loaded chitosan nanoparticles (Meth-Cs-NPs) was formulated through single-step self-assembly by incorporating the ionic-gelation method. Chitosan was cross-linked with Methotrexate via a sodium tripolyphosphate (STPP) where 49 % Methotrexate was loaded in the nanoparticles (∼143 nm) and zeta potential of 34 ± 3 mV with an entrapment efficiency of 87 %. The efficacy of nanoparticles was assessed for chemically induced breast cancer treatment in the Sprague Dawley rats model. These Meth-Cs-NPs followed the Korsmeyer-Peppas model in-vitro release kinetics. Nanoparticles were further evaluated for in-vitro efficacy on triple-negative breast cancer (MDA-MB-231) cell lines. The MTT assay studies revealed that even slight exposure to Meth-Cs-NPs (IC₅₀ = 15 µg/mL) caused 50 % cell death in 24 h. Further, hemocompatibility studies of Meth-Cs-NPs were performed, deciphered that Meth-Cs-NPs were biocompatible (hemolysis < 2 %). Additional cellular uptake was evaluated by confocal imaging. Moreover, an in-vivo pharmacokinetic study of nanoparticles in rats displayed increased plasma concentration of the drug and retention time, whereas a decrease in cellular clearance compared to free Methotrexate. Further, anti-tumor efficacy studies revealed that nanoparticles could reduce tumor volume from 1414 mm³→385 mm³ compared to free Methotrexate (1414 mm³→855 mm³). The current study presents encouraging prospects of Meth-Cs-NPs to be used as a viable breast cancer treatment modality.

Fabrication of chitosan-alginate nanospheres for controlled release of cartap hydrochloride

Insecticide cartap hydrochloride (C) was fabricated as nanospheres by a two-step method of ionic gelification and polyelectrolyte complexation of alginate (ALG) and chitosan (CS) to undermine its adverse effects on environment. Nanospheres were characterized by field emission scanning electron microscope, Fourier transform infrared spectra and x-ray diffraction. The size of cartap hydrochloride entrapped chitosan alginate nanospheres (C-CS-ALG nps) was in range of 107.58-173.07 nm. Cartap hydrochloride nanospheres showed encapsulation efficiency of 76.19% and were stable for 30 d at ambient temperature. Release of cartap from nanospheres fitted best with first order linear kinetics followed by Hixson and Higuchi model suggesting super case II transport release. With the application of such control release nanoformulations, it is possible to reduce the frequency of field application of insecticide due to its slow release to the target organism, which is economical as well as environmentally safe.