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Modification of surface of silicates materials with organic functional groups has been widely investigated in recent years. The modified materials are used in separation technology, electronic devices, controlled drug delivery and in chemical processes using immobilized catalysts. Two main methods of preparation of the materials are reviewed. The one-pot synthesis of support and its reaction with a modification agent leads to the product with even distribution of active groups but less ordered structure. The other methods are based on post-grafting of the modified support surface. The disadvantage of the latter method is often uneven distribution of active groups.
Tissue engineering is an interdisciplinary field that uses a combination of cells, suitable biomaterials and bioactive molecules to engineer the desired tissue and restore lost function. These principles have quickly begun to spread to the therapy of multiple diseases, including depigmentation disorders. The most common depigmentation disorder is vitiligo, a disease with deep psychosocial implications. Thanks to their unique properties, electrospun polymeric nanofibers represent a material suitable for tissue engineering applications. Furthermore, they may be functionalized with platelets, cells that contain a wide spectrum of growth factors and chemokines. The aim of this paper was to evaluate the functionalization of polymeric nanofibers with platelets and their effects in melanocyte culture. The scaffolds were visualized using scanning electron microscopy, the metabolic activity and proliferation of melanocytes was determined using MTS assay and dsDNA quantification, respectively. Furthermore, the melanocytes were stained and visualized using confocal microscopy. The acquired data showed that poly-ε-caprolactone functionalized with platelets promoted the viability and proliferation of melanocytes. According to the results, such a functionalized scaffold combining nanofibers and platelets may be suitable for melanocyte culture.
- MeSH
- lidé MeSH
- nanovlákna MeSH
- tkáňové inženýrství * MeSH
- trombocyty MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
The site-specific chemical modification of proteins through incorporation of noncanonical amino acids enables diverse applications, such as imaging, probing, and expanding protein functions, as well as to precisely engineer therapeutics. Here we report a general strategy that allows the incorporation of noncanonical amino acids into target proteins using the amber suppression method and their efficient secretion in the biotechnological relevant expression host Bacillus subtilis. This facilitates efficient purification of target proteins directly from the supernatant, followed by their functionalization using click chemistry. We used this strategy to site-specifically introduce norbornene lysine into a single chain antibody and functionalize it with fluorophores for the detection of human target proteins.
- MeSH
- Bacillus subtilis genetika metabolismus MeSH
- click chemie MeSH
- CRISPR-Cas systémy MeSH
- ELISA MeSH
- genetické vektory MeSH
- genetický kód MeSH
- isopropylthiogalaktosid farmakologie MeSH
- kreatinkinasa, forma MM metabolismus MeSH
- lidé MeSH
- lysin chemie MeSH
- norbornany chemie MeSH
- proteinové inženýrství metody MeSH
- regulace genové exprese u bakterií účinky léků MeSH
- rekombinantní proteiny chemie genetika izolace a purifikace metabolismus MeSH
- zelené fluorescenční proteiny genetika metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
A series of triterpenoids of the lupane, taraxastane, friedelane and baccharane type were oxidized using selenium dioxide (SeO2) and benzeneseleninic anhydride (BSA) under various conditions. Depending on the reaction conditions, different reaction pathways were observed, including dehydrogenation, allylic oxidation, and 1,2-diketone formation. In this way, derivatives functionalized in the triterpene core (especially in rings A, D, and E), difficult to obtain by other methods, can be easily prepared. In some cases, rarely observed α-phenylseleno-ketones were isolated. An unexpected reaction involving the cleavage of the carbon-carbon double bond was observed in the presence of stoichiometric amounts of osmium tetroxide. Further transformations of selected intermediates facilitated the synthesis of new, functionally enriched derivatives. The key reaction pathways were investigated using density functional theory (DFT), focusing on bond length variations and transition states, revealing energetically favored pathways and critical transition structures, including covalent and noncovalent interactions. Solvent and isomerization equilibrium effects were proposed to explain the experimentally observed discrepancies. Cytotoxic activity of selected derivatives was investigated. Derivatives 4 and 38 showed strongest cytotoxicity in cancer cells and fibroblasts (IC50 2.6-26.4 μM); some compounds were selective for G-361 or HeLa cells. These results suggest that they may find application in pharmaceuticals.
- MeSH
- lidé MeSH
- molekulární struktura MeSH
- nádorové buněčné linie MeSH
- oxidace-redukce MeSH
- pentacyklické triterpeny MeSH
- proliferace buněk účinky léků MeSH
- protinádorové látky * farmakologie chemie chemická syntéza MeSH
- screeningové testy protinádorových léčiv MeSH
- selen * chemie MeSH
- teorie funkcionálu hustoty MeSH
- triterpeny * chemie farmakologie chemická syntéza MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
A novel application of a single stranded (ss) oligonucleotide as an active component of polymeric membrane in an ion-selective electrode (ISE) is described. The original oligonucleotides, oligo(dA)(15), modified by cholesterol, triphenylmethyl and hexadecyl derivatives, were immobilized into poly(vinyl chloride) (PVC) membrane using extraction protocol. In parallel, the adsorption protocol was used to immobilize unmodified oligo(dA)(15) on the PVC membrane based on tridodecylmethyammonium chloride (TDDMA(+)Cl(-)). Immobilization of ss oligonucleotide probe through spacer was more effective for the potentiometric detection of the hybridization between complementary oligonucleotides. It was found that cholesterol-oligo(dA)(15) modified membranes were sensitive toward complementary oligo(dT)(15) in the concentration range 2-80 nM at pH 7. An explanation for the detection mechanism is proposed.
- MeSH
- analýza selhání vybavení MeSH
- biokompatibilní potahované materiály chemie MeSH
- biosenzitivní techniky metody přístrojové vybavení MeSH
- design vybavení MeSH
- DNA sondy genetika chemie MeSH
- financování organizované MeSH
- hybridizace in situ metody přístrojové vybavení MeSH
- oligonukleotidy analýza genetika chemie MeSH
- polyvinylchlorid chemie MeSH
- reprodukovatelnost výsledků MeSH
- senzitivita a specificita MeSH
- Publikační typ
- hodnotící studie MeSH
Nanoparticles functionalized with specific biological recognition molecules play a major role for sensor response enhancement in surface plasmon resonance (SPR) based biosensors. The functionalization procedure of such nanoparticles is crucial, since it influences their interactions with the environment and determines their applicability to biomolecular detection in complex matrices. In this work we show how the ζ-potential (Zpot) of bio-functionalized gold spherical NPs (Bio-NPs) is related to the SPR sensor response enhancement of an immune-sandwich-assay for the detection of the carcinoembryonic antigen (CEA), a cancer marker for colorectal carcinomas. In particular, we prepare bio-functional nanoparticles by varying the amount of peptide (either streptavidin or antibody against CEA) bound on their surface. Specific and non-specific sensor responses, reproducibility, and colloidal stability of those bio-functional nanoparticles are measured via SPR and compared to ζ-potential values. Those parameters are first measured in buffer solution, then measured again when the surface of the biosensor is exposed to blood plasma, and finally when the nanoparticles are immersed in blood plasma and flowed overnight on the biosensor. We found that ζ-potential values can guide the design of bio-functional NPs with improved binding efficiency and reduced non-specific sensor response, suitable reproducibility and colloidal stability, even in complex matrixes like blood plasma.
- MeSH
- hematologické testy metody MeSH
- karcinoembryonální antigen * krev MeSH
- krevní plazma chemie MeSH
- lidé MeSH
- nádorové biomarkery analýza MeSH
- nanočástice analýza MeSH
- peptidy analýza MeSH
- povrchová plasmonová rezonance metody MeSH
- zlato analýza MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Advanced drug delivery systems (DDS) are easily designed following a photoiterative strategy. Multifunctional polymers are obtained by coupling building blocks of interest to an alkynated poly(ε-caprolactone) (PCL) platform via an efficient thiol-yne photoaddition. Fine-tuning over the design is achieved, as illustrated with targeting and enzyme-responsive DDS.
- MeSH
- alkyny chemie MeSH
- fotochemické procesy * MeSH
- HEK293 buňky MeSH
- kurkumin aplikace a dávkování chemie MeSH
- lékové transportní systémy metody MeSH
- lidé MeSH
- nádorové buněčné linie MeSH
- nanostruktury aplikace a dávkování chemie MeSH
- polyestery chemie MeSH
- polyethylenglykoly chemie MeSH
- protinádorové látky aplikace a dávkování chemie MeSH
- sulfhydrylové sloučeniny chemie MeSH
- viabilita buněk účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Using two ways of functionalizing amiridine-acylation with chloroacetic acid chloride and reaction with thiophosgene-we have synthesized new homobivalent bis-amiridines joined by two different spacers-bis-N-acyl-alkylene (3) and bis-N-thiourea-alkylene (5) -as potential multifunctional agents for the treatment of Alzheimer's disease (AD). All compounds exhibited high inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with selectivity for BChE. These new agents displayed negligible carboxylesterase inhibition, suggesting a probable lack of untoward drug-drug interactions arising from hydrolytic biotransformation. Compounds 3 with bis-N-acyl-alkylene spacers were more potent inhibitors of both cholinesterases compared to compounds 5 and the parent amiridine. The lead compounds 3a-c exhibited an IC50(AChE) = 2.9-1.4 μM, IC50(BChE) = 0.13-0.067 μM, and 14-18% propidium displacement at 20 μM. Kinetic studies of compounds 3a and 5d indicated mixed-type reversible inhibition. Molecular docking revealed favorable poses in both catalytic and peripheral AChE sites. Propidium displacement from the peripheral site by the hybrids suggests their potential to hinder AChE-assisted Aβ42 aggregation. Conjugates 3 had no effect on Aβ42 self-aggregation, whereas compounds 5c-e (m = 4, 5, 6) showed mild (13-17%) inhibition. The greatest difference between conjugates 3 and 5 was their antioxidant activity. Bis-amiridines 3 with N-acylalkylene spacers were nearly inactive in ABTS and FRAP tests, whereas compounds 5 with thiourea in the spacers demonstrated high antioxidant activity, especially in the ABTS test (TEAC = 1.2-2.1), in agreement with their significantly lower HOMO-LUMO gap values. Calculated ADMET parameters for all conjugates predicted favorable blood-brain barrier permeability and intestinal absorption, as well as a low propensity for cardiac toxicity. Thus, it was possible to obtain amiridine derivatives whose potencies against AChE and BChE equaled (5) or exceeded (3) that of the parent compound, amiridine. Overall, based on their expanded and balanced pharmacological profiles, conjugates 5c-e appear promising for future optimization and development as multitarget anti-AD agents.
- MeSH
- acetylcholinesterasa MeSH
- Alzheimerova nemoc farmakoterapie MeSH
- aminochinoliny chemie MeSH
- antioxidancia chemie farmakologie MeSH
- butyrylcholinesterasa chemie MeSH
- cholinesterasové inhibitory chemie farmakologie MeSH
- GPI-vázané proteiny antagonisté a inhibitory MeSH
- kinetika MeSH
- lidé MeSH
- molekulární modely MeSH
- molekulární struktura MeSH
- neuroprotektivní látky chemie farmakologie MeSH
- simulace molekulového dockingu MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Late stage CH functionalization is a powerful tool for modification of natural compounds. Herein we report that the rhodium-catalyzed reaction of brassinosteroids with aryloxysulfonamides proceeds regio- and stereoselectively at C15 position. The derivative obtained from 24-epibrassinolide was easily transformed to the conjugate with a BODIPY dye bearing unaffected functional groups of the native brassinosteroid.
The increasing popularity of peptides as promising molecular scaffolds for biomedical applications and as valuable biochemical probes makes new methods allowing for their modification highly desirable. We describe herein an optimized protocol based on a sequence of CuAAC click reactions and selective deprotection steps, which leads to an efficient multi-functionalization of synthetic peptides. The methodology has been successfully applied to the construction of defined heteroglycopeptides and fluorophore-quencher-containing probes for proteases. The developed chemistry thus represents an important addition to the available toolbox of methods enabling efficient postsynthetic modification of peptides. The commercial availability of numerous azide probes further greatly extends the application potential of the described methodology.
