Sodium Dodecyl Sulphate-Supported Nanocomposite as Drug Carrier System for Controlled Delivery of Ondansetron

In Vitro Hemoglobin Binding and Molecular Docking of Synthesized Chitosan-Based Drug-Carrying Nanocomposite for Ciprofloxacin-HCl Drug Delivery System

Understanding the intermolecular interactions between antibiotic drugs and hemoglobin is crucial in biological systems. The current study aimed to investigate the preparation of chitosan/polysorbate-80/tripolyphosphate (CS-PS/TPP) nanocomposite as a potential drug carrier for Ciprofloxacin-HCl drug (CFX), intended for controlled release formulation and further used to interact with bovine hemoglobin. Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis-differential thermal analysis (TGA-DTA), scanning electron microscopy (SEM), dynamic light scattering (DLS), and X-ray diffraction analyses were used to characterize the CS-PS/TPP nanocomposite and its CFX-loaded nanocomposite. The second series of biophysical properties were performed on the Ciprofloxacin-loaded CS-PS/TPP (NCFX) for interaction with bovine hemoglobin (BHb). The interactions of (CFX and NCFX) with redox protein hemoglobin were investigated for the first time through a series of in vitro experimental techniques to provide comprehensive knowledge of the drug-protein binding interactions. Additionally, the effect of inclusion of PS-80 on the CFX-BHb interaction was also studied at different concentrations using fluorescence spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy, and circular dichroism (CD) under physiological conditions. The binding process of CFX and NCFX was spontaneous, and the fluorescence of BHb was quenched due to the static mechanism formation of the (CFX/BHb) and (NCFX/BHb) complexes. Thermodynamic parameters ΔG, ΔH, and ΔS at various temperatures indicate that the hydrogen bonding and van der Waals forces play a major role in the CFX-BHb association.

A New Phantom that Simulates Electrically a Human Blood Vessel Surrounded by Tissues: Development and Validation Against In-Vivo Measurements

This study aims to develop a phantom that simulates the electrical properties of a human blood vessel surrounded by tissues, inside which bubbles can be infused to mimic Decompression Sickness (DCS) conditions. This phantom may be used to calibrate novel electrical methods for bubbles detection in humans and study bubble dynamics during DCS. It may contribute to the limitation of in-vivo trials and time/effort saving, while its use can be extended to other biomedical applications. To facilitate the design of the phantom, we perform first in-vitro measurements in a flow-loop and in-vivo measurements in a swine, in order to detect infused bubbles of a few tenths μm-representing Decompression Sickness conditions-in the test liquid flow and blood flow, respectively, by means of "I-VED" EU patented electrical impedance spectroscopy technique. Results show that the proposed phantom, consisting of a spongy specimen soaked in agar gel in the presence of electrolyte with a hole along it, simulates adequately the electrical properties of a human blood vessel surrounded by tissues. I-VED demonstrates pretty high sensitivity to sense micro-bubbles over the partially conductive vessel walls of the phantom or the isolated animal vein, as well as in the flow-loop: bubbles presence increases electrical impedance and causes intense signal fluctuations around its mean value.

Diffusion of Vanadium Ions in Artificial Saliva and Its Elimination from the Oral Cavity by Pharmacological Compounds Present in Mouthwashes

In this study, diffusion coefficients of ammonium vanadate at tracer concentrations in artificial saliva with and without sodium fluoride, at different pH values, were measured using an experimental model based on the Taylor dispersion technique. Ternary mutual diffusion coefficients (D11, D22, D12, and D21) for four aqueous systems {NH4VO3 (component 1) + β-cyclodextrin (β-CD) (component 2),} {NH4VO3 (component 1) + β-cyclodextrin (HP-β-CD) (component 2)}, {NH4VO3 (component 1) + sodium dodecyl sulphate (SDS) (component 2)} and {NH4VO3 (component 1) + sodium hyaluronate (NaHy) (component 2)} at 25.00 °C were also measured by using the same technique. These data showed that diffusion of ammonium vanadate was strongly affected in all aqueous media studied. Furthermore, a significant coupled diffusion of this salt and β-CD was observed through the non-zero values of the cross-diffusion coefficients, D12, allowing us to conclude that there is a strong interaction between these two components. This finding is very promising considering the removal, from the oral cavity, of vanadium resulting from tribocorrosion of Ti-6Al-4V prosthetic devices.

Highly Tough, Stretchable, and Enzymatically Degradable Hydrogels Modulated by Bioinspired Hydrophobic β-Sheet Peptides

Peptide-based supramolecular hydrogels have attracted great attention due to their good biocompatibility and biodegradability and have become promising candidates for biomedical applications. The bottom-up self-assembly endows the peptides with a highly ordered secondary structure, which has proven to be an effective strategy to improve the mechanical properties of hydrogels through strong physical interactions and energy dissipation. Inspired by the excellent mechanical properties of spider-silk, which can be attributed to the rich β-sheet crystal formation by the hydrophobic peptide fragment, a hydrophobic peptide (HP) that can form a β-sheet assembly was designed and introduced into a poly(vinyl alcohol) (PVA) scaffold to improve mechanical properties of hydrogels by the cooperative intermolecular physical interactions. Compared with hydrogels without peptide grafting (P-HP0), the strong β-sheet self-assembly domain endows the hybrid hydrogels (P-HP20, P-HP29, and P-HP37) with high strength and toughness. The fracture tensile strength increased from 0.3 to 2.1 MPa (7 times), the toughness increased from 0.4 to 21.6 MJ m^-3 (54 times), and the compressive strength increased from 0.33 to 10.43 MPa (31 times) at 75% strain. Moreover, the hybrid hydrogels are enzymatically degradable due to the dominant contribution of the β-sheet assembly for network cross-linking. Combining the good biocompatibility and sustained drug release of the constructed hydrogels, this hydrophobic β-sheet peptide represents a promising candidate for the rational design of hydrogels for biomedical applications.

Preparation, Characterization, and Anti-Cancer Activity of Nanostructured Lipid Carriers Containing Imatinib

Breast cancer is the most widespread malignancy in women worldwide. Nanostructured lipid carriers (NLCs) have proven effective in the treatment of cancer. NLCs loaded with imatinib (IMA) (NANIMA) were prepared and evaluated for their in vitro efficacy in MCF-7 breast cancer cells. The hot homogenization method was used for the preparation of NANIMAs. An aqueous solution of surfactants (hot) was mixed with a molten mixture of stearic acid and sesame oil (hot) under homogenization. The prepared NANIMAs were characterized and evaluated for size, polydispersity index, zeta potential, encapsulation efficiency, release studies, stability studies, and MTT assay (cytotoxicity studies). The optimized NANIMAs revealed a particle size of 104.63 ± 9.55 d.nm, PdI of 0.227 ± 0.06, and EE of 99.79 ± 0.03. All of the NANIMAs revealed slow and sustained release behavior. The surfactants used in the preparation of the NANIMAs exhibited their effects on particle size, zeta potential, encapsulation efficiency, stability studies, and release studies. The cytotoxicity studies unveiled an 8.75 times increase in cytotoxicity for the optimized NANIMAs (IC₅₀ = 6 µM) when compared to IMA alone (IC₅₀ = 52.5 µM) on MCF-7 breast cancer cells. In the future, NLCs containing IMA will possibly be employed to cure breast cancer. A small amount of IMA loaded into the NLCs will be better than IMA alone for the treatment of breast cancer. Moreover, patients will likely exhibit less adverse effects than in the case of IMA alone. Consequently, NANIMAs could prove to be useful for effective breast cancer treatment.

Surface-Induced Crystallization of Sodium Dodecyl Sulfate (SDS) Micellar Solutions in Confinement

We investigate the role of confinement on the onset of crystallization in subcooled micellar solutions of sodium dodecyl sulfate (SDS), examining the impact of sample volume, substrate surface energy, and surface roughness. Using small angle neutron scattering (SANS) and dynamic light scattering (DLS), we measure the crystallization temperature upon cooling and the metastable zone width (MSZW) for bulk 10-30 wt% SDS solutions. We then introduce a microdroplet approach to quantify the impact of surface free energy (18-65 mN/m) and substrate roughness (R_α ≃ 0-60 μm) on the kinetics of surface-induced crystallization through measurements of induction time (t_i) under isothermal conditions. While t_i is found to decrease exponentially with decreasing temperature (increasing subcooling) for all tested surfaces, increasing the surface energy could cause a significant further reduction of up to ∼40 fold. For substrates with the lowest surface energy and longest t_i, microscale surface roughness is found to enhance crystal nucleation, in particular for R_α ≥ 10 μm. Finally, we demonstrate that tuning the surface energy and microscopic roughness can be effective routes to promote or delay nucleation in bulk-like volumes, thus greatly impacting the stability of surfactant solutions at lower temperatures.

Fabrication and Characterization of Polysorbate/Ironmolybdophosphate Nanocomposite: Ion Exchange Properties and pH-responsive Drug Carrier System for Methylcobalamin

Background:

Nanocomposites are of great interest due to their competency to show multifunctional properties. They have been recently given much attention due to their credibility to offer the synergistic feature of organic material with those of inorganic constituents. Different types of nanocomposites have been prepared to date and are being used for different applications. The delivery of drugs in the human body at a particular site was one of the major problems in the medicinal field. The nanocomposite formulations can be used to provide controlled release and they can be combined with ligands for targeted drug delivery. Applications of the nanocomposites as ion exchangers are also increasing at a faster rate. Due to this, they help in the softening of the water. They can also be easily recharged by washing them with a solution containing a high concentration of sodium ions. In the present paper, we have worked on the synthesis and applications of the polysorbate/ironmolybdophosphate (PS/FMP) nanocomposite.

Methods:

Polysorbate/ironmolybdophosphate (PS/FMPS) was synthesized by co-precipitation method in the presence of polysorbate. The material was well characterized using X-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy, (FTIR) scanning transmission microscopy (SEM), and transmission electron microscopy (TEM). Physicochemical properties of material were studied in detail. Drug delivery behavior of polysorbate/ironmolybdophosphate was investigated by using methylcobalamin as a test drug.

Results:

The polysorbate/ironmolybdophosphate nanocomposite show enhanced Na+ ion exchange capacity of 2.1 meq/g. It has been revealed that PS/FMP nanocomposite was thermally stable as it retained the ion exchange capacity of 40.4 % at 400°C. An optimum concentration of sodium nitrate (eluent) was found to be 1.0 M for the complete removal of H+ ions from the PS/FMP column. The optimum volume of sodium nitrate (eluent) was found to be 230 mL. The FTIR spectra showed the changes in intensities of characteristic peaks in PS/FMP and in drug loaded on PS/FMP nanocomposite. The characteristic peak at 1043-1061 cm-1 was observed for ionic phosphate stretching, 560-567 cm-1 for iron group and 959 cm-1 due to molybdate present in the material. The additional peak at 3390 cm-1 and 1711 cm-1 were due to -OH and C=O stretching due to the presence of these groups in the structure of polysorbate. The peak present at 430 cm-1 might be due to the presence of Co-O stretching of methylcobalamin. The XRD results confirmed the semicrystalline structure of FMP and PS/FMP. Scanning electron micrographs results revealed the beaded surface of FMP changes to fibrous surface in case of PS/FMP nanocomposite. The TEM images indicate the appearance of smooth surfactant layer on the surface of FMP. The size of the nanocomposite is between 10- 70 nm. The drug loading efficiency and encapsulation efficiency were found to be 35.2%. and 60.4%, respectively. The cumulative drug release of methylcobalamin was studied for the PS/FMP nanocomposite. The order of drug release was found to be pH 9.4 (54.6%) > pH 7.4 (46.4%) > saline (pH 5.7) (36.2%) > pH 2.2 (33.9%). The release at pH 9.4 was higher. As the pH of medium changes from acidic to basic i.e. 2.2 - 9.4, there is an appreciable increase in drug release from the PS/FMP nanocomposite due to the presence of more OH- ions resulting in neutralization of cationic nanocomposite and thus increasing the rate of drug release by ion exchange process and matrix deterioration.

:

The novel nanocomposite PS/FMP has been synthesized by a simple co-precipitation method. The increase in Na+ ion exchange capacity for nanocomposite is due to the binding of organic part (Polysorbate) with inorganic ironmolybdophosphate. The physiochemical properties of PS/FMP were found to be superior. Fourier transform infrared spectra of PS/FMP and drug loaded PS/FMP confirmed the formation of materials. The SEM results indicated the surface of synthesized FMP is bead-like appearance whereas the beaded surface of FMP changes to fibrous surface on the addition of polysorbate thus indicated the fabrication of nanocomposite. The cumulative drug release of methylcobalamin was studied and the order of drug release was found to be pH 9.4 > pH 7.4 > saline (pH 5.7) > pH 2.2. Thus PS/FMP is a promising multifunctional nanocomposite.

Magnetic Nano-Сomposites and their Industrial Applications

Magnetic nanocomposites are multi-component, nanosized magnetic materials, to generate the response to an external stimulus (i.e., outer inert or alternative magnetic field). The novel nanocomposites is a combination of excess of various materials such as liquid crystals, silica, gels, renewable polymers, carbon along with different magnetic particles. They have immense applications in the field of medical diagnosis and therapy, catalysis and separation. These nanocarriers are mainly classified into nanotubes, nanosheets, spherical nanoparticles, nanofibres, highly porous nanocomposites. The porous nanostructures provides a better surface for the entrapment or covalent binding of enzymes, proteins, biomolecules and drugs but the major challenge is to design and synthesize a desired structure with suitable surface properties and biocompatibility. Extensive attempts have been made to manipulate the mesoporous materials and its combination with other structure in order to synthesize a matrix with appropriate pore size, large surface area to volume ratio. “Bottom-up” and “Bottom-down” chemical-based synthesis methods have been widely employed to prepare magnetic nanoparticles. Magnetic nanocomposites are synthesized from magnetic nanoparticles and biopolymers by using sol-gel technique, chemical precipitation methods and NanogenTM, a microwave plasma method. In this chapter, we described the advances and developments in the formation/synthesis of magnetic nanocomposites. This chapter will review the characteristics, properties and applications of the magnetic nanocomposites.