Partner: Monika Bil

Warsaw University of Technology (PL)

Recent publications
1.Urbanek O., Pierini F., Choińska E., Sajkiewicz P., Bil M., Święszkowski W., Effect of hydroxyapatite nanoparticles addition on structure properties of poly(L-lactide-co-glycolide) after gamma sterilization, Polymer Composites, ISSN: 0272-8397, DOI: 10.1002/pc.24028, Vol.1, pp.1-9, 2016
Abstract:

Physical and chemical factors resulting from the sterilization methods may affect the structure and properties of the materials which undergo this procedure. Poly(l-lactide-co-glicolide) (PLGA) is commonly used for medical applications, but, due to its inadequate mechanical properties, it is not recommended for load-bearing applications. One of the methods for improving PLGA mechanical properties is addition of hydroxyapatite nanoparticles (nHAp). The aim of this study was to evaluate the effect of nanoparticles addition on PLGA structure and properties after gamma radiation. According to our results, reduction of the molecular mass caused by gamma radiation was lower for PLGA with nHAp addition. Differential scanning calorimetry (DSC) analysis indicates an increase of crystallinity caused both by nHAp and gamma radiation. The first phenomenon can be explained by heteronucleation, while the second one is most probably related to higher molecular mobility of degrading polymer. Moreover, addition of nanoparticles increases thermal stability and affects the Young's modulus changes after gamma radiation.

Affiliations:
Urbanek O.-IPPT PAN
Pierini F.-IPPT PAN
Choińska E.-Warsaw University of Technology (PL)
Sajkiewicz P.-IPPT PAN
Bil M.-Warsaw University of Technology (PL)
Święszkowski W.-other affiliation

Conference abstracts
1.Kołbuk D., Denis P., Bil M., Sajkiewicz P., Influence of Crystallinity and Selected Mechanical Properties on Cellular Response, ICMAT2015, 8th International Conference on Materials for Advanced Technologies and IUMRS – International Conference in Asia, 2015-06-28/07-03, Suntec (SG), No.M-PO2, 2015
Abstract:

Cells sense subtract stiffness, elasticity and transduce that information into morphological changes and lineage specification. Polymer molecular order and mechanical properties, specially stiffness and elasticity indicate influence on cellular response during in- vitro study [e.g. Bershadskye et al 2013]. The aim of proposed presentation is to evaluate the effect of tailored crystallinity and mechanical properties of one- and bicomponent polymer films in terms of cells morphology and proliferation without changing other parameters. Polycaprolactone (PCL) and Gelatin (Ge) were used. As a solvents: Hexafluoroisopropanole (H), Acetic Acid (AA) were chosen. Two methods of foil preparation were analysed: forming from melt (onecomponent), forming from solution (one- and bicomponent).In both methods, the degree of crystallinity was modified mainly by the different type of PCL molecular weight, solvent type and/or annealing. Films were analysed using polarizinginterference microscopy allowing characterization of spherulities morphology. Degree of crystallinity was analysed by differential scanning calorimetry. Foils topography was analysed by atomic force microscopy, selected mechanical properties and hydrophilicity (contact angle) as the significant from the viewpoint of cellular activity were determined as well. L929 cells adhesion and morphology ware analysed by immunohistochemical staining for actin and nuclei. Cell activity and proliferation were analysed also. It is evident that conditions of PCL films preparation affect the morphology of spherulites. All samples were birefringent, indicating in general crystallinity, being different for particular samples. Maltese cross was observed in few samples. Crystallinity of PCL films determined from DSC measurements was in range 0,45-0,70 depending on solvent and polymer molecular weight used. Young Modulus strongly depends on Mw of PCL and Ge additive. L929 cells interact with subtract; morphology and proliferation degree change with crystallinity and elasticity of one- and bicomponet films.

Keywords:

crystallinity, PCL, mechanical properties, casted films

Affiliations:
Kołbuk D.-IPPT PAN
Denis P.-IPPT PAN
Bil M.-Warsaw University of Technology (PL)
Sajkiewicz P.-IPPT PAN
2.Urbanek O., Bil M., Święszkowski W., The effect of hydroxyapatite nanoparticles addition on crystallinity and surface properties of bioresorbable nanocomposites after gamma sterylization treatment, 4th Summer Symposium on Nanomaterials and Their Application to Biology and Medicine, 2014-06-15/06-18, Poznań (PL), pp.1, 2014