The manufacturing of modern scaffolds with customized geometry and personalization has become possible due to the three‐dimensional (3D) printing technique. A novel type of 3D‐printed scaffolds for bone tissue regeneration based on poly(ε‐caprolactone) (PCL) filled with nanocrystalline cellulose modified by poly(glutamic acid) (PGlu‐NCC) has been proposed in this study. The 3D printing set‐ups were optimized in order to obtain homogeneous porous scaffolds. Both polymer composites and manufactured 3D scaffolds have demonstrated mechanical properties suitable for a human trabecular bone. Compression moduli were in the range of 334–396 MPa for non‐porous PCL and PCL‐based composites, and 101–122 MPa for porous scaffolds made of the same materials. In vitro mineralization study with the use of human mesenchymal stem cells (hMSCs) revealed the larger Ca deposits on the surface of PCL/PGlu‐NCC composite scaffolds. Implantation of the developed 3D scaffolds into femur of the rabbits was carried out to observe close and delayed effects. The histological analysis showed the lowest content of immune cells and thin fibrous capsule, revealing low toxicity of the PCL/PGlu‐NCC scaffolds seeded with rabbit MSCs (rMSCs) to the surrounding tissues. The most pronounced result on the generation of new bone tissue after implantation of PCL/PGlu‐NCC + rMSCs scaffolds was detected by both microcomputed tomography and histological analysis. Around 33% and 55% of bone coverage were detected for composite 3D scaffolds with adhered rMSCs after 1 and 3 months of implantation, respectively. This achievement can be a result of synergistic effect of PGlu, which attracts calcium ions, and stem cells with osteogenic potential.

A new biocompatible nanocomposite film material for cell engineering and other biomedical applications has been prepared. It is based on the composition of natural polysaccharides filled with cerium oxide nanoparticles (CeONPs). The preparative procedure consists of successive impregnations of pressed bacterial cellulose (BC) with a sodium alginate (ALG) solution containing nanoparticles of citrate-stabilized cerium oxide and a chitosan (CS) solution. The presence of CeONPs in the polysaccharide composite matrix and the interaction of the nanoparticles with the polymer, confirmed by IR spectroscopy, change the network architecture of the composite. This leads to noticeable changes in a number of properties of the material in comparison with those of the matrix’s polysaccharide composition, viz., an increase in mechanical stiffness, a decrease in the degree of planar orientation of BC macrochains, an increase in hydrophilicity, and the shift of the processes of thermo-oxidative destruction of the material to a low-temperature region. The latter effect is considered to be caused by the redox activity of cerium oxide (reversible transitions between the states Ce4+ and Ce3+) in thermally stimulated processes in the nanocomposite films. In the equilibrium swollen state, the material retains a mechanical strength at the level of ~2 MPa. The results of in vitro tests (cultivation of multipotent mesenchymal stem cells) have demonstrated the good biocompatibility of the BC-ALG(CeONP)-CS film as cell proliferation scaffolds.

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A set of nanocomposite film materials based on bacterial cellulose containing nanoparticles of cerium dioxide was prepared. An investigation into the structural and morphological characteristics of the films has been performed, their thermal, mechanical and tribological properties were determined. A protocol of the nanocomposite materials formation used in the work was shown to provide a homogeneous distribution of ceria nanoparticles in the matrix polymer volume in addition to the presence of certain amount of broadly size-dispersed cerium oxide aggregates in the bulk film. The increase of nanoparticles concentration in the composite provokes a progressive growth of the Young's modulus and strength of the film material. Introduction of nanoparticles into the polymer causes the stabilization of sliding friction processes in the tribocontact with steel as well as the decrease of intensity in the wear rate of the film. An increase of the nanoparticles concentration results in a decrease of the material thermal stability.

Novel poly(amide‐imide)s and poly(amide‐o‐hydroxy‐imide)s were synthesized in the process of low‐temperature polycondensation of diacid chloride of 2‐(4‐carboxyphenyl)‐1,3‐dioxoisoindoline‐5‐carboxylic acid with a single diamine of 5,5′‐methylenebis(2‐aminophenol (DADHyDPhM) or of 4,4′‐methylenebis(benzeneamine) (DADPhМ), and also with a mixture of named diamines (molar ratios of DADHyDPhM to DADPhМ being equal to 7:3, 1:1, and 3:7). The influence of hydroxy‐imide modifying units (fragments) introduced into the basic poly(amide‐imide) on its thermal stability (the processes of polymers destruction proceed intensively in the temperature range from 400 to 600°C and has a complex character); parameters of pervaporation through heat‐resistant films prepared from polymer solutions were analyzed. Polymer films are rigid materials (modulus of elasticity–3 to 4 GPa) with a strength above 100 MPa. Heating up to 300°C leads for all three compositions to a noticeable increase in the elastic modulus and to a pronounced tendency to increase the strength characteristics.