Tomas Saha

Dr. Tomas Saha

Tomas Bata University in Zlin

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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16 December 2020 in Polymers
Verified
Journal Article
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FNFahanwi Asabuwa Ngwabebhoh
Fahanwi Asabuwa Ngwabebhoh
Nabanita SahaNabanita Saha
Nabanita Saha
HNHau Trung Nguyen
Hau Trung Nguyen
Urška Vrabič-BrodnjakUrška Vrabič-Brodnjak
Urška Vrabič-Brodnjak
TSTomas Saha
Tomas Saha
PSPetr Saha
Petr Saha
Chromium-tanned leathers used in the manufacture of footwear and leather goods pose an environmental problem because they contain harmful chemicals and are very difficult to recycle. A solution to this problem can be composite materials from tree leaves, fruit residues and other fibrous agricultural products, which can replace chromium-tanned leather. The present study describes the preparation of biocomposite leather-like materials from microbial cellulose and maple leave fibers as bio-fillers. The formulation was optimized by design of experiment and the prepared biocomposites characterized by tensile test, FTIR, DMA, SEM, adhesion test, volume porosity, water absorptivity, surface wettability and shape stability. From the viewpoint of future use in the footwear industry, results obtained showed that the optimized material was considerably flexible with tensile strength of 2.13 ± 0.29 MPa, elastic modulus of 76.93 ± 1.63 MPa and porosity of 1570 ± 146 mL/min. In addition, the material depicted good shape stability and surface adhesive properties. The results indicate that a suitable treatment of biomass offers a way to prepare exploitable nonwoven fibrous composites for the footwear industry without further burdening the environment.

16 December 2020 in Polymers
Verified
Journal Article
Open access
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NSNibedita Saha
Nibedita Saha
Nabanita SahaNabanita Saha
Nabanita Saha
TSTomas Saha
Tomas Saha
EOEbru Toksoy Oner
Ebru Toksoy Oner
Urška Vrabič-BrodnjakUrška Vrabič-Brodnjak
Urška Vrabič-Brodnjak
PSPetr Saha
Petr Saha
This article deliberates about the importance of polymer-based bioadhesive biomaterials’ medical application in healthcare and in redefining healthcare management. Nowadays, the application of bioadhesion in the health sector is one of the great interests for various researchers, due to recent advances in their formulation development. Actually, this area of study is considered as an active multidisciplinary research approach, where engineers, scientists (including chemists, physicists, biologists, and medical experts), material producers and manufacturers combine their knowledge in order to provide better healthcare. Moreover, while discussing the implications of value-based healthcare, it is necessary to mention that health comprises three main domains, namely, physical, mental, and social health, which not only prioritize the quality healthcare, but also enable us to measure the outcomes of medical interventions. In addition, this conceptual article provides an understanding of the consequences of the natural or synthetic polymer-based bioadhesion of biomaterials, and its significance for redefining healthcare management as a novel approach. Furthermore, the research assumptions highlight that the quality healthcare concept has recently become a burning topic, wherein healthcare service providers, private research institutes, government authorities, public service boards, associations and academics have taken the initiative to restructure the healthcare system to create value for patients and increase their satisfaction, and lead ultimately to a healthier society.

10 October 2021 in Polymers
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Journal Article
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Smarak BandyopadhyaySmarak Bandyopadhyay
Smarak Bandyopadhyay
TSTomas Saha
Tomas Saha
DSDaniel Sanetrnik
Daniel Sanetrnik
Nabanita SahaNabanita Saha
Nabanita Saha
PSPetr Saha
Petr Saha
There is a gap in the literature for the preparation of agar-xanthan gum-carboxymethyl cellulose-based films by thermo compression methods. The present work aims to fill this gap by blending the polysaccharides in a plastograph and preparation of films under high pressure and temperature for a short duration of time. The pivotal aim of this work is also to know the effect of different mixing conditions on the physical, chemical, mechanical and thermal properties of the films. The films are assessed based on results from microscopic, infrared spectroscopic, permeability (WVTR), transmittance, mechanical, rheological and thermogravimetric analysis. The results revealed that the mixing volume and mixing duration had negative effects on the films’ transparency. WVTR was independent of the mixing conditions and ranged between 1078 and 1082 g/m2·d. The mixing RPM and mixing duration had a positive effect on the film tensile strength. The films from the blends mixed at higher RPM for a longer time gave elongation percentage up to 78%. Blending also altered the crystallinity and thermal behavior of the polysaccharides. The blend prepared at 80 RPM for 7 min and pressed at 140 °C showed better percent elongation and light barrier properties.

18 December 2020 in Journal of Clinical Medicine
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MMMarjan Motiei
Marjan Motiei
KVKaterina Vaculikova
Katerina Vaculikova
ACAndrea Cela
Andrea Cela
KTKaterina Tvrdonova
Katerina Tvrdonova
RKReza Khalili
Reza Khalili
TSTomas Saha
Tomas Saha
The selection of a highly-viable single embryo in assisted reproductive technology requires an acceptable predictive method in order to reduce the multiple pregnancy rate and increase the success rate. In this study, the metabolomic profiling of growing and impaired embryos was assessed on the fifth day of fertilization using capillary electrophoresis in order to find a relationship between the profiling and embryo development, and then to provide a mechanistic insight into the appearance/depletion of the metabolites. This unique qualitative technique exhibited the appearance of most non-essential amino acids and lactate, and depleting the serine, alanyl-glutamine and pyruvate in such a manner that the embryos impaired in their development secreted a considerably higher level of lactate and consumed a significantly higher amount of alanyl-glutamine. The different significant ratios of metabolomic depletion/appearance between the embryos confirm their potential for the improvement of the prospective selection of the developed single embryos, and also suggest the fact that pyruvate and alanyl-glutamine are the most critical ATP suppliers on the fifth day of blastocyst development.

13 March 2023 in Coatings
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Journal Article
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FNFahanwi Asabuwa Ngwabebhoh
Fahanwi Asabuwa Ngwabebhoh
OZOyunchimeg Zandraa
Oyunchimeg Zandraa
TSTomas Saha
Tomas Saha
JSJaroslav Stejskal
Jaroslav Stejskal
DKDušan Kopecký
Dušan Kopecký
Jiří PflegerJiří Pfleger
Jiří Pfleger
In the search for functional organic biomaterials, leather constituted by collagen fibers was coated with a conducting polymer, polypyrrole. The coating was carried out during the oxidation of pyrrole in an aqueous solution of poly(N-vinylpyrrolidone) in the presence of five organic dyes: crystal violet, neutral red, methyl orange, acriflavine, and methylene blue. This technique ensures the uniform coating of collagen fibers with polypyrrole and incorporation of organic dyes. The surface morphology was observed with scanning electron microscopy and the transverse profile, reflecting the penetration of the conducting phase into the leather body with optical microscopy. While the polypyrrole coating endows leather with electrical conductivity, organic dyes are expected to affect the polymer morphology and to provide an antibacterial effect. The lowest sheet resistance and antibacterial activity were obtained with crystal violet. This type of coating was characterized in more detail. Infrared spectroscopy confirmed the coating of collagen fibers with polypyrrole and dye incorporation. Mechanical properties were extended to the cyclic bending of the leather at various angles over 5000 cycles. The relative resistance changes were a few percent, indicating good electrical stability during repeated mechanical stress.

8 April 2021 in Polymers
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Journal Article
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Kadir OzaltinKadir Ozaltin
Kadir Ozaltin
Antonio Di MartinoAntonio Di Martino
Antonio Di Martino
ZCZdenka Capakova
Zdenka Capakova
Marian LehockyMarian Lehocky
Marian Lehocky
Petr HumpolíčekPetr Humpolíček
Petr Humpolíček
PSPetr Saha
Petr Saha
The development of antibacterial materials has great importance in avoiding bacterial contamination and the risk of infection for implantable biomaterials. An antibacterial thin film coating on the surface via chemical bonding is a promising technique to keep native bulk material properties unchanged. However, most of the polymeric materials are chemically inert and highly hydrophobic, which makes chemical agent coating challenging Herein, immobilization of chlorhexidine, a broad-spectrum bactericidal cationic compound, onto the polylactic acid surface was performed in a multistep physicochemical method. Direct current plasma was used for surface functionalization, followed by carbodiimide chemistry to link the coupling reagents of N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (EDAC) and N-Hydroxysuccinimide (NHs) to create a free bonding site to anchor the chlorhexidine. Surface characterizations were performed by water contact angle test, X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM). X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM). The antibacterial activity was tested using Staphylococcus aureus and Escherichia coli. Finally, in vitro cytocompatibility of the samples was studied using primary mouse embryonic fibroblast cells. It was found that all samples were cytocompatible and the best antibacterial performance observed was the Chlorhexidine immobilized sample after NHs activation.