Effect of the enzymatically modified supported dipalmitoylphosphatidylcholine (DPPC) bilayers on calcium carbonate formation

Polymeric and Composite Carriers of Protein and Non-Protein Biomolecules for Application in Bone Tissue Engineering

Conventional intake of drugs and active substances is most often based on oral intake of an appropriate dose to achieve the desired effect in the affected area or source of pain. In this case, controlling their distribution in the body is difficult, as the substance also reaches other tissues. This phenomenon results in the occurrence of side effects and the need to increase the concentration of the therapeutic substance to ensure it has the desired effect. The scientific field of tissue engineering proposes a solution to this problem, which creates the possibility of designing intelligent systems for delivering active substances precisely to the site of disease conversion. The following review discusses significant current research strategies as well as examples of polymeric and composite carriers for protein and non-protein biomolecules designed for bone tissue regeneration.

Ligand-receptor interaction in the specific targeting of biomimetic peptide nanoparticles to lysophosphatidylcholine

As nanotechnology is applied clinical medicine, nanoparticle-based therapy is emerging as a novel approach for the treatment of atherosclerosis. Ligand-receptor interaction affects the effectiveness of nanoparticle targeting therapy. In this study, the biomimetic peptide (BP-KFFVLK-WYKDGD) ligand specifically targeting the lysophosphatidylcholine (LPC) receptor in atherosclerotic plaques was constructed. The corresponding ligand-receptor interaction under different pH values was investigated by molecular dynamics simulation and experimental measurements. Results show that the interaction force between the peptide and LPC is greater than that of the peptide and human umbilical vein endothelial cell, clearly demonstrating the specific targeting of the peptide ligand to the LPC receptor. The ligand-receptor binding of peptide and LPC dominantly depends on Coulomb and van der Waals interactions. The YKDG amino acids of the peptide are the main fragment that binds to LPC. Compared with neutral environment at pH 7.4, the interaction forces between the peptide and oxidized low-density lipoprotein (oxLDL) decreased by 18.22 % and 45.87 % under acidic environments at pH 6.5 and 5.5, respectively, because of the change in oxLDL secondary structure and the release of LPC from oxLDL. Nevertheless, the peptide still has a strong binding capacity with oxLDL for the treatment of atherosclerosis.

Intrinsic Effect of Nanoparticles on the Mechanical Rupture of Doubled-Shell Colloidal Capsule via In Situ TEM Mechanical Testing and STEM Interfacial Analysis

The discovery of Pickering emulsion templated assembly enables the design of a hybrid colloidal capsule with engineered properties. However, the underlying mechanisms by which nanoparticles affect the mechanical properties of the shell are poorly understood. Herein, in situ mechanical compression on the transmission electron microscope and aberration-corrected scanning transmission microscope are unprecedentedly implemented to study the intrinsic effect of nanoparticles on the mechanical properties of the calcium carbonate (CaCO₃ )-decorated silica (SiO₂ ) colloidal capsule. The stiff and brittle nature of the colloidal capsule is due to the interfacial chemical bonding between the CaCO₃ nanoparticles and SiO₂ inner shell. Such bonding strengthens the mechanical strength of the SiO₂ shell (166 ± 14 nm) from the colloidal capsule compared to the thicker single SiO₂ shell (310 ± 70 nm) from the silica hollow sphere. At elevated temperature, this interfacial bonding accelerates the formation of the single calcium silicate shell, causing shell morphology transformation and yielding significantly enhanced mechanical strength by 30.9% and ductility by 94.7%. The superior thermal durability of the heat-treated colloidal capsule holds great potential for the fabrication of the functional additives that can be applied in the wide range of applications at elevated temperatures.