Filtry
wszystkich: 1940
wybranych: 1534
-
Katalog
- Publikacje 1534 wyników po odfiltrowaniu
- Czasopisma 28 wyników po odfiltrowaniu
- Konferencje 2 wyników po odfiltrowaniu
- Osoby 11 wyników po odfiltrowaniu
- Projekty 3 wyników po odfiltrowaniu
- Kursy Online 117 wyników po odfiltrowaniu
- Wydarzenia 1 wyników po odfiltrowaniu
- Dane Badawcze 244 wyników po odfiltrowaniu
Filtry wybranego katalogu
wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: polylactic acid
-
Thermal degradation of polylactic acid (PLA)/polyhydroxybutyrate (PHB) blends: A systematic review
PublikacjaPolylactic acid (PLA) and polyhydroxybutyrate (PHB) are two biopolyesters obtained from renewable resources like corn or sugar under bacterial fermentation. PLA is the most widely used biopolymer in diverse applications. Addition of PHB to PLA can improves the crystallinity of PLA, and thereby its mechanical strength. However, both PLA and PHB suffer from poor thermal stability, which limits their potential industrial application....
-
High-performance polylactic acid compressed strawboard using pre-treated and functionalised wheat straw
Publikacja -
Preparation of a Ceramic Matrix Composite Made of Hydroxyapatite Nanoparticles and Polylactic Acid by Consolidation of Composite Granules
Publikacja -
Matcha Green Tea: Chemical Composition, Phenolic Acids, Caffeine and Fatty Acid Profile
Publikacja -
Tensile and Fatigue Behavior of Additive Manufactured Polylactide
PublikacjaThis article presents the results of monotonic tensile and fatigue tests conducted on commercial polylactide or polylactic acid (PLA). The results of fatigue tests for this material present in the literature are limited, especially for additive manufactured elements. The specimens were manufactured using the injection molding and the fused filament fabrication (FFF) method. The FFF specimens were divided into five subgroups, depending...
-
Antibacterial Porous Systems Based on Polylactide Loaded with Amikacin
PublikacjaThree porous matrices based on poly(lactic acid) are proposed herein for the controlled release of amikacin. The materials were fabricated by the method of spraying a surface liquid. Description is given as to the possibility of employing a modifier, such as a silica nanocarrier, for prolonging the release of amikacin, in addition to using chitosan to improve the properties of the materials, e.g., stability and sorption capacity....
-
Synthesis and biological activity of mycophenolic acid-amino acid derivatives
Publikacja -
Anticancer Properties of Amino Acid and Peptide Derivatives of Mycophenolic Acid
PublikacjaBackground: Although Mycophenolic Acid (MPA) is applied as prodrugs in clinic as an immunosuppressant, it also possesses anticancer activity. MPA acts as Inosine-5’-Monophosphate Dehydrogenase (IMPDH) inhibitor, where the carboxylic group at the end of the side chain interacts with Ser 276 of the enzyme via hydrogen bonds. Therefore, MPA derivatives with other polar groups indicated high inhibition too. On the other hand, potent...
-
Hyaluronic acid/tannic acid films for wound healing application
PublikacjaIn this study, thin films based on hyaluronic acid (HA) with tannic acid (TA) were investigated in three different weight ratios (80HA/20TA, 50HA/50TA, 20HA/80TA) for their application as materials for wound healing. Surface free energy, as well as their roughness, mechanical properties, water vapor permeability rate, and antioxidant activity were determined. Moreover, their compatibility with blood and osteoblast cells was investigated....
-
Immunosuppressive properties of amino acid and peptide derivatives of mycophenolic acid
PublikacjaMycophenolic acid (MPA) was coupled with amino acids and biologically active peptides including derivatives of tuftsin to modify its immunosuppressive properties. Both amino acid unit in the case of simple MPA amides and modifications within peptide moiety of MPA - tuftsin conjugates influenced the observed activity. Antiproliferative potential of the obtained conjugates was investigated in vitro and MPA amides with threonine methyl...
-
Synthesis and biological activity of mycophenolic acid-amino acid derivatives
PublikacjaIn search of new immunosuppressants, mycophenolic acid (MPA) was coupled with amino acid methyl esters followed by hydrolysis to analogs bearing free carboxylic groups. The obtained compunds were tested in vitro as growth inhibitors of lymphoid cell line (Jurkat) and human peripheral blood mononuclear cells (PBMC) from healthy donors. According to obtained results recovering of free carboxylic group increased their activity. Additionally,...
-
Susceptibility to Degradation in Soil of Branched Polyesterurethane Blends with Polylactide and Starch
PublikacjaA very important method of reducing the amount of polymer waste in the environment is the introduction to the market of polymers susceptible to degradation under the influence of environmental factors. This paper presents the results of testing the susceptibility to degradation in soil of branched polyesterurethane (PUR) based on poly([R,S]-3-hydroxybutyrate) (R,S-PHB), modified with poly([D,L]-lactide) (PLA) and starch (St). Weight...
-
Synthesis and antimicrobial activity of amino acid and peptide derivatives of mycophenolic acid
PublikacjaThe series of 16 novel amino acid and peptide mycophenolic acid (MPA) derivatives was obtained as potential antibacterial agents. Coupling of MPA with respective amines was optimized with condensing reagents such as EDCI/DMAP and T3P/TEA. Amino acid analogs were received both as methyl esters and also with the free carboxylic group. The biological activity of the products was tested on five references bacterial strains: Klebsiella...
-
Novel Cell Permeable Polymers of N-Substituted L-2,3-Diaminopropionic Acid (DAPEGs) and Cellular Consequences of Their Interactions with Nucleic Acids
Publikacja -
Antibacterial Films Based on Polylactide with the Addition of Quercetin and Poly(Ethylene Glycol)
Publikacja -
Polylactide Films with the Addition of Olive Leaf Extract—Physico-Chemical Characterization
Publikacja -
Influence of the Type of Amino Acid on the Permeability and Properties of Ibuprofenates of Isopropyl Amino Acid Esters
Publikacja -
The physicochemical properties of 3D materials based on hyaluronic acid modified by tannic acid addition
Publikacja -
New Analogues of Mycophenolic Acid
PublikacjaMycophenolic acid (MPA) possesses antibacterial, antifungal, antiviral, immunosuppressive and anticancer properties. It is a non-competitive and reversible inhibitor of dehydrogenase inosine-5'-monophosphate (IMPDH). This compound belongs to the immunosuppressive drugs used for the prevention of both acute and chronic transplant rejection. Until now, two derivatives of MPA have been used clinically: mycophenolate mofetil (MMF,...
-
Experimental study on the effect of selected sterilization methods on mechanical properties of polylactide FFF specimens
PublikacjaPurpose: Biodegradable polymers are widely used in personalized medical devices or scaffolds for tissue engineering. The manufacturing process should be finished with sterilization procedure. However, it is not clear how the different sterilization methods have an impact on the mechanical strength of the three-dimensional (3D)-printed parts, such as bone models or personalized mechanical devices. This paper aims to present the...
-
Updates in the Metabolism of Lactic Acid Bacteria
Publikacja -
Structural Analysis of 3,5-Bistrifluoromethylhydrocinnamic Acid
Publikacja -
Amino acid formation by electron irradiation
PublikacjaW artykule zaprezentowano procedurę badania reakcji indukowanych przez niskoenergetyczne elektrony w mieszanych warstwach molekularnych CH3COOD:NH3.
-
Modifications of total synthesis of mycophenolic acid
PublikacjaThe total synthesis of mycophenolic acid (MPA), a potent immunosuppressant, was modified. The obtained mycophenolic acid was suitable for further preparation of new prospective immunosuppressants with improved therapeutic properties.
-
Elicitation of solid callus cultures of Salvia miltiorrhiza Bunge with salicylic acid and a synthetic auxin (1-naphthaleneacetic acid)
Publikacja -
Equilibrium and kinetic studies on acid dye Acid Red 88 adsorption by magnetic ZnFe2O4 spinel ferrite nanoparticles
Publikacja -
Ultrashort Cationic Lipopeptides–Effect of N-Terminal Amino Acid and Fatty Acid Type on Antimicrobial Activity and Hemolysis
Publikacja -
Constituents of Propolis: Chrysin, Caffeic Acid, p-Coumaric Acid, and Ferulic Acid Induce PRODH/POX-Dependent Apoptosis in Human Tongue Squamous Cell Carcinoma Cell (CAL-27)
Publikacja -
Helium-assisted, solvent-free electro-activation of 3D printed conductive carbon-polylactide electrodes
PublikacjaFused filament fabrication is one of the most rapidly developing 3D printing techniques, with numerous applications, including in the field of applied electrochemistry. Here, the utilisation of conductive carbon black polylactic acid (CB-PLA) for 3D printouts is the most promising. To use CB-PLA as an electrode material, an activation process must be performed, removing the polymer matrix and uncovering the electrically conductive...
-
Composites of polylactide and nano-hydroxyapatite created by cryomilling and warm isostatic pressing for bone implants applications
Publikacja -
Real-time monitoring of the emission of volatile organic compounds from polylactide 3D printing filaments
PublikacjaEstablishing the emission profile of volatile organic compounds generated during fused deposition modeling 3D printing using polymer filaments is important in terms of both understanding the processes taking place during thermal degradation of thermoplastics, and assessing the user's exposure to potentially harmful volatiles. However, obtaining detailed, real-time qualitative and quantitative results poses a challenge. In this...
-
One Year Evaluation of Material Properties Changes of Polylactide Parts in Various Hydrolytic Degradation Conditions
PublikacjaBiodegradable biocompatible materials are widely used in medical applications. Determining the possibility of using biodegradable materials depends on determining the changes in their parameters over time due to degradation. The current scientific research on biodegradable materials has presented results based on research methods characterized by the different geometry and cross-section size of the specimen, type of degradation...
-
Adsorption Kinetics of Acid Dye Acid Red 88 onto Magnetic Multi‐Walled Carbon Nanotubes‐Fe3C Nanocomposite
Publikacja -
Efficient Diethylzinc/Gallic Acid and Diethylzinc/Gallic Acid Ester Catalytic Systems for the Ring-Opening Polymerization of rac-Lactide
Publikacja -
Microstructural behavior of water-in-oil emulsions stabilized by fatty acid esters of propylene glycol and zinc fatty acid salts
PublikacjaZbadano wpływ składu emulgatorów acylopropylenoglikolowych, modyfikowanych mydłami cynku, na charakter przemian strukturalnych jakim ulegają emulsje W/O stabilizowane przez takie emulgatory. Badano zarówno etap emulgowania jak i mikrostrukturę oraz właściwości reologiczne otrzymanych emulsji.
-
Investigation of an elutable N-propylphosphonic acid chitosan derivative composition with a chitosan matrix prepared from carbonic acid solution
PublikacjaPorous chitosan composites using CO2 dissolution procedure and including water soluble N-propylphosphonic chitosan derivative (p-CHI) were obtained and characterized. In contrast to the control material, composites containing modified chitosan distinguished by a rapid moisture absorption and good adhesion to the skin. The FTIR analysis confirmed the presence of propylphosphonic group in the structure of the polymer. The porosity...
-
(S)-N-Nitrosoazetidine-2-carboxylic acid.
PublikacjaAnaliza rentgenograficzna monokryształów kwasu (S)-N-nitozoazetydyno-2-karboksylowego wykazała, że reszta N-nitrozoaminowa przyjmuje konfigurację E. Azetydynowy atom azotu jest nieznacznie piramidalny. Cząsteczki w sieci krystalicznej oddziałują ze sobą poprzez wiązania wodorowe pomiędzy atomem tlenu grupy nitrozowej i atomem wodoru grupy karboksylowej, tworząc polimeryczny łańcuch.
-
Hydrogen charging of nitrided steel in acid solution
PublikacjaKonstrukcyjną stal, azotowaną w wyładowaniu jarzeniowym w mieszaninie gazów o różnej zawartości N2, H2 i Ar, poddawano katodowemu nawodorowaniu w kwaśnym roztworze, imitującym przepracowany olej maszynowy. W pomiarach szybkości przenikania wodoru i ekstrakcji próżniowej określano wpływ azotowanych warstw, odpowiednio, na transport wodoru i na jego nieodwracalne pułapkowanie. W obecności niezdefektowanej warstwy kompaktowych azotków...
-
May dithiophosphoric acid participate in the set process?
PublikacjaZastosowano otrzymane S-tioacyloditiofosforany jako odczynniki tioacylujące do syntezy kwasów tiohydroksamowych. Dla większości N-alkilohydroksyloamin produktem tej reakcji były żądane kwasy tiohydroksamowe. Natomiast gdy substratem jest hydroksyloamina zawierająca duży objętościowo podstawnik na atomie azotu lub gdy posiada dwa podstawniki na atomie azotu w reakcji tej tworzą się wyłącznie odpowiednie O-tioacylohydroksyloaminy....
-
Amino Acid and Peptide‐Based Antiviral Agents
PublikacjaA significant number of antiviral agents used in clinical practice are amino acids, short peptides, or peptidomimetics. Among them, several HIV protease inhibitors (e. g. lopinavir, atazanavir), HCV protease inhibitors (e. g. grazoprevir, glecaprevir), and HCV NS5A protein inhibitors have contributed to a significant decrease in mortality from AIDS and hepatitis. However, there is an ongoing need for the discovery of new antiviral...
-
Dissociative electron attachment to benzoic acid (C7H6O2)
PublikacjaThe dissociative electron attachment (DEA) to benzoic acid (C6H5COOH) has been studied using an experimental crossed beam setup of a quadrupole mass spectrometer and a trochoidal electron monochromator. Relative partial cross sections for the DEA to produce negative ion fragments show the main channels for dissociation. The comparison of the present results with the ultraviolet photoelectron spectrum of benzoic acid [J. Meeks,...
-
Easy formation of acyl-Meldrum's acid anhydride
PublikacjaAcyl Meldrum's acid are usually a good source of ketenes upon definite thermal composition. However we treated acyl-Meldrum's acid with the Lewis acid and we observed formation of 5[[(2,2-dimethyl-4,6-dioxo-1,3-dioxan 5 ylidene)(acyl/arylamino)mathoxy](acyl/arylamino)methylene]-2,2dimethyl-1,3-dioxane-4,6 dione which means acyl-Meldrum's acid anhydride. The chemical properities of acyl-Meldrum's acid anhydride were explored.
-
The Reason Why HAlCl4 Acid Does Not Exist
Publikacja -
Glycyrrhetinic acid and its derivatives in infectious diseases
Publikacja -
The 2:1 cocrystal of benzamide and pentafluororbenzoic acid
PublikacjaKrystaliczna struktura centrosymetrycznej supermolekuły składa się z czterech cząsteczek benzamidu oraz dwóch kwasu karboksylowego, które powiązane są ze sobą za pomocą wiązań wodorowych typu O-H...O oraz N-H...O.
-
New conjugates of mycophenolic acid and their antiproliferative activity
PublikacjaThe new conjugates of mycophenolic acid (MPA) were obtained in the reaction of N6-(ω-aminoalkyl)adenosines with MPA in the presence of EDCI as a coupling reagent. New compounds 4a–h were evaluated on leukemia cell line (Jurkat) and PBMC from healthy donors. Length of the linker influenced observed activity. The compound 4b possessing 1,3-diamine spacer exhibited the most promising results and can be considered to further investigations.
-
Cytotoxic and Antioxidant Activities of Benzohydroxamic Acid Analogues
Publikacja20 benzohydroxamic acid analogues were synthesized and evaluated for their in vitro cytotoxicities against mouse mammary tumor cells as well as antioxidant activities against DPPH radical and superoxide anion. It was found that benzothiohydroxamic acids exhibit greater cytotoxicities than benzohydroxamic acids and N-isopropyl derivatives are more active than N-methyl ones. On the other hand, benzothiohydroxamic acids show more...
-
ASCORBIC ACID IN POLYURETHANE SYSTEMS FOR TISSUE ENGINEERING
PublikacjaThe introduction of the paper was devoted to the main items of tissue engineering (TE) and the way of porous structure obtaining as scaffolds. Furthermore, the significant role of the scaffold design in TE was described. It was shown, that properly designed polyurethanes (PURs) find application in TE due to the proper physicochemical, mechanical and biological properties. Then the use of L-ascorbic acid (L-AA) in PUR systems for...
-
Phenazine - 2,6-dihydroxybenzoic acid (1/1)
PublikacjaOtrzymano krystaliczny kompleks fenazyny z kwasem 2,6-dihydroksybenzoesowym o stechiometrii 1:1. Badania struktury kompleksu za pomocą metod rentgenograficznych wykazały, że powiązane wiązaniami wodorowymi typu OH...N cząsteczki fenazyny układają się w stosy, które stabilizowane są poprzez oddziaływania typu π-π pierścieni aromatycznych. Cząsteczki kwasu zajmują przestrzenie kanałów tworzonych pomiędzy kolumnami pierścieni aromatycznych...
-
Encapsulation of Amikacin into Microparticles Based on Low-Molecular-Weight Poly(lactic acid) and Poly(lactic acid-co-polyethylene glycol)
PublikacjaThe aim of this study was to fabricate novel microparticles (MPs) for efficient and long-term delivery of amikacin (AMI). The emulsification method proposed for encapsulating AMI employed low-molecular-weight poly(lactic acid) (PLA) and poly(lactic acid-co-polyethylene glycol) (PLA−PEG), both supplemented with poly(vinyl alcohol) (PVA). The diameters of the particles obtained were determined as less than 30 μm. Based on an in-vitro...