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1.
Gels ; 10(6)2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38920952

RESUMEN

Fabrication of scaffolds via 3D printing is a promising approach for tissue engineering. In this study, we combined 3D printing with cryogenic crosslinking to create biocompatible gelatin/oxidized alginate (Gel/OxAlg) scaffolds with large pore sizes, beneficial for bone tissue regeneration. To enhance the osteogenic effects and mechanical properties of these scaffolds, we evaluated the impact of hydroxyapatite (HAp) on the rheological characteristics of the 2.86% (1:1) Gel/OxAlg ink. We investigated the morphological and mechanical properties of scaffolds with low, 5%, and high 10% HAp content, as well as the resulting bio- and osteogenic effects. Scanning electron microscopy revealed a reduction in pore sizes from 160 to 180 µm (HAp-free) and from 120 to 140 µm for both HAp-containing scaffolds. Increased stability and higher Young's moduli were measured for 5% and 10% HAp (18 and 21 kPa, respectively) compared to 11 kPa for HAp-free constructs. Biological assessments with mesenchymal stem cells indicated excellent cytocompatibility and osteogenic differentiation in all scaffolds, with high degree of mineralization in HAp-containing constructs. Scaffolds with 5% HAp exhibited improved mechanical characteristics and shape fidelity, demonstrated positive osteogenic impact, and enhanced bone tissue formation. Increasing the HAp content to 10% did not show any advantages in osteogenesis, offering a minor increase in mechanical strength at the cost of significantly compromised shape fidelity.

2.
Molecules ; 28(14)2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37513290

RESUMEN

Species of the genus Artemisia are well known for their use as ingredients in ancient medicine. The advantage of using plant extracts compared to individual pharmaceutical ingredients is the rate of adaptation of the pathogenic microorganisms to the drug. Due to the rapid development of multidrug-resistance in microorganisms in the field, it is essential to search for novel, effective drugs with low toxicity. Therefore, the purpose of this study was to isolate and study the biologically active substances obtained from various substances in the raw materials of Artemisia cina Berg. The identification of the main biologically active components was performed using the method of chromato-mass spectrometry. Moreover, the antiviral activity of several extracts was studied using the method of measuring limiting dilutions (the Reed-Mench method), with some modifications. For the first time, the biological activity of extracts from the raw material of Artemisia cina Berg. upon the SARS-CoV-2 virus was confirmed. All the obtained extracts exhibited nontoxic effects in animals, with an LD50 greater than 2 g/kg. Comprehensive toxicological analyses are also presented in the study, such as those of the biochemical parameters of urine after one day and one week of the extracts' administration in mice at a dose of 2 g/kg body weight. In all groups of animals that received extracts of Artemisia cina Berg., a slight increase in the presence of red blood cells in their urine was observed one day following the administration of the extracts. This increase decreased somewhat after a week; however, it remained higher than the levels observed in the control animals. In the three groups, there was also a slight increase in the amount of ketones in the urine. Two weeks following the administration of the extracts to these groups, the internal organs of the animals were examined. The examination showed that the internal organs of the animals that received the extracts were not visibly different from those of the control animals in terms of their size or appearance. The weight of the internal organs of the animals that received the extracts was also similar to the weight of the internal organs of the control animals, illustrating the absence of toxicity.


Asunto(s)
Artemisia , COVID-19 , Animales , Ratones , Artemisia/química , Antivirales/farmacología , SARS-CoV-2 , Extractos Vegetales/química , Preparaciones Farmacéuticas
3.
Mini Rev Med Chem ; 2023 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-37448365

RESUMEN

BACKGROUND: This review summarizes data on heterocyclic systems with thiadiazole and thiazole fragments in molecules as promising antimicrobial agents. INTRODUCTION: Thiadiazole and thiazole backbones are the most favored and well-known heterocycles, a common and essential feature of various drugs. These scaffolds occupy a central position and are the main structural components of numerous drugs with a wide spectrum of action. These include antimicrobial, antituberculous, anti-inflammatory, analgesic, antiepileptic, antiviral, and anticancer agents. METHOD: The research is based on bibliosemantic and analytical methods using bibliographic and abstract databases, as well as databases of chemical compounds. RESULT: This review reports on thiadiazole and thiazole derivatives, which have important pharmacological properties. We are reviewing the structural modifications of various thiadiazole and thiazole derivatives, more specifically, the antimicrobial activity reported over the last years, as we have taken this as our main research area. 80 compounds were illustrated, and various derivatives containing hydrazone bridged thiazole and pyrrole rings, 2-pyridine and 4-pyridine substituted thiazole derivatives, compounds containing di-, tri- and tetrathiazole moieties, Spiro-substituted 4-thiazolidinone-imidazoline-pyridines were analyzed. Derivatives of 5-heteroarylidene-2,4-thiazolidinediones, fluoroquinolone-thiadiazole hybrids, and others. CONCLUSION: 1,3,4-thiadiazoles and thiazoles are valuable resource for researchers engaged in rational drug design and development in this area.

4.
Polymers (Basel) ; 15(5)2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36904477

RESUMEN

The present study deals with the synthesis and characterization of a polymer composite based on an unsaturated ester loaded with 5 wt.% triclosan, produced by co-mixing on an automated hardware system. The polymer composite's non-porous structure and chemical composition make it an ideal material for surface disinfection and antimicrobial protection. According to the findings, the polymer composite effectively inhibited (100%) the growth of Staphylococcus aureus 6538-P under exposure to physicochemical factors, including pH, UV, and sunlight, over a 2-month period. In addition, the polymer composite demonstrated potent antiviral activity against human influenza virus strain A and the avian coronavirus infectious bronchitis virus (IBV), with infectious activities of 99.99% and 90%, respectively. Thus, the resulting triclosan-loaded polymer composite is revealed to have a high potential as a surface-coating non-porous material with antimicrobial properties.

5.
Saudi Pharm J ; 30(7): 1036-1043, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35903529

RESUMEN

Un unsolvable issue of a significant number increase of drug multi resistant strains of microorganisms including Mycobacterium tuberculosis force researchers for continuous design novel pharmaceuticals. The purpose of the study is the establishment of the correlation between the structure of novel heterocyclic hydrazide derivatives and their biological activity. Several hydrazide derivatives of N-piperidinyl and N-morpholinyl and propionic acids and N-piperidinyl acetic and their derivatives were synthesized via condensation of corresponding esters with hydrazine hydrate.The structure of synthesized compounds were confirmed by the use of FTIR, H1NMR, Mass-spectroscopy and element analysis. Investigation of synthesized substances using PASS software was carried out to predict probability of pharmacological activity in silico. The antibacterial, antifungal and spasmolytic activity as well as acute toxicity of obtained compounds were evaluated in vivo. 2-(N-piperidinyl)acetic acid hydrazide and 2-methyl-3-N-piperidinyl)propanacid hydrazide revealed antibacterial and spasmolytic activities comparable to the model drugs (drotaverin) in vitro study. Synthesized compounds in in vivo experiment showed significantly low acute toxicity (LD50 520-5750 mg/kg) compared to commercially available drugs (streptomicine, ciprofloxacinum and drotaverin LD50 100-215 mg/kg). The structure- activity relationship was established that the increasing of the length of the linker between heterocyclic amine and hydrazide group results in a decrease of antimicrobial activity against studied strains (Escherichia coli, Salmonella typhymurium, Salmonella choleraesuis, Staphylococcus aureus).

6.
Molecules ; 27(7)2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35408695

RESUMEN

The use of enterosorbents-materials which can be administered orally and eliminate toxic substances from the gastrointestinal tract (GIT) by sorption-offers an attractive complementary protection of humans against acute and chronic poisoning. In this study, we report the results of developing a microgranulated binary biomedical preparation for oral use. It was designed with a core-shell structure based on pectin with low degree of esterification as the core, and nanoporous activated carbon produced from rice husk, AC-RH, as the shell, designated as AC-RH@pectin. The adsorption properties of the synthesized materials were studied in aqueous solutions for the removal of lead (II) nitrate as a representative of toxic polyvalent metals and sodium diclofenac as an example of a medicinal drug. The composite enterosorbent demonstrated high adsorption capacity for both adsorbates studied. Adsorption kinetics of lead and diclofenac adsorption by AC-RH, pectin, and AC-RH@pectin, fitted well a pseudo-second-order model. According to the Langmuir adsorption isotherm model, the best fitted isotherm model, the maximum adsorption capacity, qmax, of AC-RH@pectin for diclofenac and for lead (II) was 130.9 mg/g and 227.8 mg/g, respectively. Although qmax of AC-RH for diclofenac, 537.6 mg/g, and qmax of pectin for lead (II), 245.7 mg/g, were higher, the maximum adsorption capacity of AC-RH for lead (II), 52.7 mg/g, was much lower than that of the composite AC-RH@pectin and the adsorption capacity of pectin for diclofenac was negligible. Therefore, the composite material AC-RH@pectin demonstrated substantial efficiency of removing both species which potentially defines it as a more universal enterosorbent suitable for treating poisoning caused by substances of different chemical nature.


Asunto(s)
Carbón Orgánico , Contaminantes Químicos del Agua , Adsorción , Carbón Orgánico/química , Diclofenaco/química , Humanos , Concentración de Iones de Hidrógeno , Cinética , Plomo/toxicidad , Pectinas/química , Contaminantes Químicos del Agua/química , Xenobióticos
7.
Medicina (Kaunas) ; 58(4)2022 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-35454302

RESUMEN

Background and Objectives: Providing a proper quality control of drugs is essential for efficient treatment of various diseases minimizing the possible side effects of pharmaceutical active substances and potential impurities. Recent in vitro and in vivo studies have shown that certain heavy metalloids and metals interfere with protein folding of nascent proteins in cells and their biological function can be altered. It is unknown whether the drug impurities including heavy metals may affect the tertiary protein structure. Materials and Methods: ReciGen and Rebif are pharmaceutical interferon beta-1a (IFNß-1a) contained in preparations that are used for parenteral administration. Heavy metal impurities of these samples have been studied by gel electrophoresis, Fourier-transform infrared spectroscopy (FTIR) and inductively coupled plasma mass spectrometry analysis (ICP MS). The concentration of heavy metals including mercury, arsenic, nickel, chromium, iron, and aluminum did not exceed permitted levels established by International Council for Harmonisation guideline for elemental impurities. Results: The ICP MS analysis revealed the presence of heavy metals, moreover zeta potential was significantly different for IFNß-1a, which can be an indirect indication of the difference in composition of ReciGen and Rebif samples, respectively. FTIR analysis revealed very similar amide I and II bonds at 1654 and 1560 cm-1 attributed to the peptide absorption peaks of IFNß-1a in Rebif and ReciGen. Conclusions: It was hypothesized that the IFNß-1a complex binds heavy metals affecting the tertiary protein structure and may lead to some side effects of drug administration. Further testing of IFNß-1a bioequivalence for parenteral application is necessary.


Asunto(s)
Interferón beta , Metales Pesados , Humanos , Interferón beta-1a , Interferón beta/uso terapéutico , Iones , Metales Pesados/toxicidad , Preparaciones Farmacéuticas
8.
Polymers (Basel) ; 14(4)2022 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-35215588

RESUMEN

The manufacturing of sanitary and household furniture on a large scale with inherently antimicrobial properties is an essential field of research. This work focuses on the synthesis of polymer composites based on the unsaturated polyester of resin loaded with 5 wt.%-Triclosan produced by a co-mixing approach on automated technological complex with a potential for broad applications. According to findings, the polymer composite has a non-porous structure (surface area < 1.97 m2/g) suitable for sanitary applications to reduce the growth of bacteria. The chemical composition confirmed the presence of major elements, and the inclusion of Triclosan was quantitatively confirmed by the appearance of chlorine on XRF (1.67 wt.%) and EDS (1.62 wt.%) analysis. Thermal analysis showed the difference of 5 wt.% in weight loss, which confirms the loading of Triclosan into the polymer matrix. The polymer composite completely inhibited the strains of S. aureus 6538-P, S. aureus 39, S. epidermidis 12228, and Kl. Pneumoniae 10031 after 5-min contact time. The antimicrobial effects against Kl. pneumoniae 700603, Ps. aeruginosa 9027 and Ps. aeruginosa TA2 strains were 92.7%, 85.8% and 18.4%, respectively. The inhibition activity against C. albicans 10231 and C. albicans 2091 was 1.6% and 82.4%, respectively; while the clinical strain of C. albicans was inhibited by 92.2%. The polymer composite loaded with 5 wt.%-Triclosan displayed a stability over the period that illustrates the possibility of washing the composite surface.

9.
Molecules ; 27(4)2022 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-35208994

RESUMEN

Rumex confertus belongs to the genus Rumex and is classified as an invasive parasitic plant in agriculture. Despite other Rumex species being widely used in herbal medicine due to their antimicrobial, antioxidant, antitumor, and anti-inflammatory effects, there are almost no information about the potential of Rumex confertus for the treatment of various diseases. In this review we analyzed scientific articles revealing properties of Rumex plant's substances against cancer, diabetes, pathogenic bacterial invasions, viruses, inflammation, and oxidative stress for the past 20 years. Compounds dominating in each composition of solvents for extraction were discussed, and common thin layer chromatography(TLC) and high performance liquid chromatography(HPLC) methods for efficient separation of the plant's extract are included. Physico-chemical properties such as solubility, hydrophobicity (Log P), pKa of flavonoids, anthraquinones, and other derivatives are very important for modeling of pharmacokinetic and pharmacodynamics. An overview of clinical studies for abounded selected substances of Rumex species is presented.


Asunto(s)
Antraquinonas/uso terapéutico , Flavonoides/uso terapéutico , Rumex/química , Antraquinonas/química , Antibacterianos/química , Antibacterianos/uso terapéutico , Antiinflamatorios/química , Antiinflamatorios/uso terapéutico , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/uso terapéutico , Antioxidantes/química , Antioxidantes/uso terapéutico , Flavonoides/química
10.
Molecules ; 26(24)2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34946690

RESUMEN

The effectiveness of an amphoteric cryogel (AAC) as an oral sorbent (enerosorbent) for the treatment of acute poisoning of small animals (rats) with heavy metals (HMs) was studied in in vivo experiments. The morphological structure of the cryogel was examined using scanning electron microscopy/energy-dispersive X-ray analysis and confocal microscopy. The use of the cryogel in the treatment of rats administered an LD50 dose of Cd(NO3)2, CsNO3, Sr(NO3)2, or HgCl2 in aqueous solution showed their high survival rate compared to the control group, which did not receive such treatment. The histological and chemical analysis of internal tissues and the biochemical analysis of the blood of the experimental animals showed the effectiveness of the cryogel in protecting the animals against the damaging effect of HMs on the organism comparable with unithiol, a chelating agent based on 2,3-dimercapto-1-propane sulfonic acid sodium salt (DMPS) approved for the treatment of acute poisoning with some heavy metals.


Asunto(s)
Antídotos , Quelantes , Criogeles , Intoxicación por Metales Pesados/tratamiento farmacológico , Animales , Antídotos/síntesis química , Antídotos/química , Antídotos/farmacología , Quelantes/síntesis química , Quelantes/química , Quelantes/farmacología , Criogeles/síntesis química , Criogeles/química , Criogeles/farmacología , Intoxicación por Metales Pesados/metabolismo , Masculino , Metales Pesados/metabolismo , Ratas
11.
Pharmaceutics ; 13(12)2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34959332

RESUMEN

Despite their conventional and widespread use, oral and intravenous routes of drug administration face several limitations. In particular, orally administered drugs undergo enzymatic degradation in the gastrointestinal tract and first-pass metabolism in the liver, which tend to decrease their bioavailability. Intravenous infusions of medications are invasive, painful and stressful for patients and carry the risk of infections, tissue damage and other adverse reactions. In order to account for these disadvantages, alternative routes of drug delivery, such as transdermal, nasal, oromucosal, ocular and others, have been considered. Moreover, drug formulations have been modified in order to improve their storage stability, solubility, absorption and safety. Recently, stimuli-responsive polymers have been shown to achieve controlled release and enhance the bioavailability of multiple drugs. In this review, we discuss the most up-to-date use of stimuli-responsive materials in order to optimize the delivery of medications that are unstable to pH or undergo primary metabolism via transdermal, nasal, oromucosal and ocular routes. Release kinetics, diffusion parameters and permeation rate of the drug via the mucosa or skin are discussed as well.

12.
Medicina (Kaunas) ; 57(11)2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34833427

RESUMEN

Peptide-based drug delivery systems have many advantages when compared to synthetic systems in that they have better biocompatibility, biochemical and biophysical properties, lack of toxicity, controlled molecular weight via solid phase synthesis and purification. Lysosomes, solid lipid nanoparticles, dendrimers, polymeric micelles can be applied by intravenous administration, however they are of artificial nature and thus may induce side effects and possess lack of ability to penetrate the blood-brain barrier. An analysis of nontoxic drug delivery systems and an establishment of prospective trends in the development of drug delivery systems was needed. This review paper summarizes data, mainly from the past 5 years, devoted to the use of peptide-based carriers for delivery of various toxic drugs, mostly anticancer or drugs with limiting bioavailability. Peptide-based drug delivery platforms are utilized as peptide-drug conjugates, injectable biodegradable particles and depots for delivering small molecule pharmaceutical substances (500 Da) and therapeutic proteins. Controlled drug delivery systems that can effectively deliver anticancer and peptide-based drugs leading to accelerated recovery without significant side effects are discussed. Moreover, cell penetrating peptides and their molecular mechanisms as targeting peptides, as well as stimuli responsive (enzyme-responsive and pH-responsive) peptides and peptide-based self-assembly scaffolds are also reviewed.


Asunto(s)
Nanopartículas , Preparaciones Farmacéuticas , Sistemas de Liberación de Medicamentos , Péptidos , Estudios Prospectivos
13.
Gels ; 7(4)2021 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-34698152

RESUMEN

We investigated the water sorption properties of macroporous cryogels of gelatine (Gel) and dextran dialdehyde (DDA) prepared via cryogelation at 260 K and following the freeze drying processes. Water vapour sorption isotherms for aerogels were studied at 293 K by two independent methods: static-gravimetric and dynamic vapour sorption (DVS) over a water activity range of 0.11-1.0. Experimental data were fitted by use of the Brunauer-Emmett-Teller (BET) and Guggenheim-Anderson-de Boer (GAB) models. The BET model (for a water activity range of 0.1 ≤ p/po ≤ 0.5) was used to calculate the sorption parameters of the studied cryogels (the monolayer capacity, surface area and energy of interaction). In comparison with BET, the GAB model can be applied for the whole range of water activities (0.1 ≤ p/po ≤ 0.95). This model gave an almost perfect correlation between the experimental and calculated sorption isotherms using nonlinear least squares fitting (NLSF). Confocal Laser Scanning Microscopy (CLSM) was used to confirm the structural differences between various DDA:Gel cryogel compositions. Thermogravimetric analysis and DSC data for aerogels DDA:Gel provided information regarding the bonded water loss, relative remaining water content of the material and the temperature of decomposition. Estimation of the amount of bound water in the cryogels after the freeze drying process as well as after the cycle of treatment of cryogels with high humidity and drying was performed using DSC. The results of the DSC determinations showed that cryogels with higher gelatin content had higher levels of bonded water.

14.
Polymers (Basel) ; 13(7)2021 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-33805360

RESUMEN

Bioremediation is a key process for reclaiming polluted soil and water by the use of biological agents. A commonly used approach aims to neutralise or remove harmful pollutants from contaminated areas using live microorganisms. Generally, immobilised microorganisms rather than planktonic cells have been used in bioremediation methods. Activated carbon, inorganic minerals (clays, metal oxides, zeolites), and agricultural waste products are acceptable substrates for the immobilisation of bacteria, although there are limitations with biomass loading and the issue with leaching of bacteria during the process. Various synthetic and natural polymers with different functional groups have been used successfully for the efficient immobilisation of microorganisms and cells. Promise has been shown using macroporous materials including cryogels with entrapped bacteria or cells in applications for water treatment and biotechnology. A cryogel is a macroporous polymeric gel formed at sub-zero temperatures through a process known as cryogelation. Macroporous hydrogels have been used to make scaffolds or supports for immobilising bacterial, viral, and other cells. The production of composite materials with immobilised cells possessing suitable mechanical and chemical stability, porosity, elasticity, and biocompatibility suggests that these materials are potential candidates for a range of applications within applied microbiology, biotechnology, and research. This review evaluates applications of macroporous cryogels as tools for the bioremediation of contaminants in wastewater.

15.
ACS Omega ; 5(42): 27582-27590, 2020 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-33134722

RESUMEN

Urea sensors based on electrodes in direct contact with the medium have limited long-term stability when exposed to complex media. Here, we present a urea biosensor based on urease immobilized in an alginate polymer, buffered at pH 6, and placed in front of a newly developed fast and sensitive CO2 microsensor, where the electrodes are shielded by a gas-permeable membrane. The CO2 produced by the urease in the presence of urea diffuses into the microsensor and is reduced at a Ag cathode. Oxygen interference is prevented by a Cr2+ trap. The 95% response time to changes in urea concentration was 120 s with a linear calibration curve in the range 0-1000 µM and a detection limit of 1 µM. The Ni2+ cofactor to improve sensor performance was continuously supplied from a reservoir behind the sensor tip. The stability of the urea sensor was optimized by the addition of bovine serum albumin as a stabilizer to the urease/alginate mixture that was cross-linked with glutaraldehyde and Ca2+ ions. This immobilization strategy resulted in about 70% of the initial urea sensor sensitivity after two weeks of continuous operation. The sensor was successfully tested in blood serum.

16.
Polymers (Basel) ; 12(10)2020 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-33086639

RESUMEN

In this study amphoteric cryogels were synthesized by the use of free-radical co-polymerization of acrylate-based precursors (methacrylic acid and 2-acrylamido-2-methyl-1-propansulfonic acid) with allylamine at different ratios. The physico-chemical characteristics of the cryogels were examined using SEM/EDX, FT-IR, XPS and zeta potential measurements. The cryogels were tested toward Cd2+ removal from aqueous solutions at various pH and initial concentrations. Equilibrium studies revealed a maximum sorption capacity in the range of 132-249 mg/g. Leaching experiments indicated the stability of Cd2+ in the cryogel structure. Based on kinetics, equilibrium and characterization results, possible removal mechanisms are proposed, indicating a combination of ion exchange and complexation of Cd2+ with the cryogels' surface functional groups. The cryogels were compared to commercially available adsorbents (zeolite Y and cation exchange resin) for the removal of Cd2+ from various water matrices (ultrapure water, tap water and river water) and the results showed that, under the experimental conditions used, the cryogels can be more effective adsorbents.

17.
Adv Colloid Interface Sci ; 276: 102088, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31887574

RESUMEN

The physical and chemical attributes of cryogels, such as the macroporosity, elasticity, water permeability and ease of chemical modification have attracted strong research interest in a variety of areas, such as water purification, catalysis, regenerative medicine, biotechnology, bioremediation and biosensors. Cryogels have shown high removal efficiency and selectivity for heavy metals, nutrients, and toxic dyes from aqueous solutions but there are challenges when scaling up from lab to commercial scale applications. This paper represents an overview of the most recent advances in the use of cryogels for the removal of heavy metals from water and attempts to fill the gap in the literature by deepening the understanding on the mechanisms involved, which strongly depend on the initial monomer composition and post-modification agent precursors used in synthesis. The review also describes the advantages of cryogels over other adsorbents and covers synthesis and characterization methods such as SEM/EDS, TEM, FTIR, zeta potential measurements, porosimetry, swelling and mechanical properties.

18.
Pharmaceutics ; 11(12)2019 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-31817064

RESUMEN

Macroporous scaffolds composed of chitosan (CHI), hydroxyapatite (HA), heparin (Hep), and polyvinyl alcohol (PVA) were prepared with a glutaraldehyde (GA) cross-linker by cryogelation. Addition of PVA to the reaction mixture slowed down the formation of a polyelectrolyte complex (PEC) between CHI and Hep, which allowed more thorough mixing, and resulted in the development of the homogeneous matrix structure. Freezing of the CHI-HA-GA and PVA-Hep-GA mixture led to the formation of a non-stoichiometric PEC between oppositely charged groups of CHI and Hep, which caused further efficient immobilization of bone morphogenic protein 2 (BMP-2) possible due to electrostatic interactions. It was shown that the obtained cryogel matrix released BMP-2 and supported the differentiation of rat bone marrow mesenchymal stem cells (rat BMSCs) into the osteogenic lineage. Rat BMSCs attached to cryogel loaded with BMP-2 and expressed osteocalcin in vitro. Obtained composite cryogel with PEC may have high potential for bone regeneration and tissue engineering applications.

19.
Biomolecules ; 9(9)2019 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-31509976

RESUMEN

Over the last few decades, chitosan has become a good candidate for tissue engineering applications. Derived from chitin, chitosan is a unique natural polysaccharide with outstanding properties in line with excellent biodegradability, biocompatibility, and antimicrobial activity. Due to the presence of free amine groups in its backbone chain, chitosan could be further chemically modified to possess additional functional properties useful for the development of different biomaterials in regenerative medicine. In the current review, we will highlight the progress made in the development of chitosan-containing bioscaffolds, such as gels, sponges, films, and fibers, and their possible applications in tissue repair and regeneration, as well as the use of chitosan as a component for drug delivery applications.


Asunto(s)
Materiales Biocompatibles/farmacología , Quitosano/farmacología , Medicina Regenerativa/métodos , Ingeniería de Tejidos/métodos , Animales , Materiales Biocompatibles/química , Quitosano/química , Humanos
20.
Water Res ; 153: 324-334, 2019 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-30739074

RESUMEN

The aim of this study was to develop and test a non-diffusion limited, high cell density bioreactor for biodegradation of various phenol derivatives. The bioreactor was obtained using a straightforward one-step preparation method using cryostructuration and direct cross-linking of bacteria into a 3D structured (sponge-like) macroporous cryogel composite material consisting of 11.6% (by mass) cells and 1.2-1.7% polymer, with approximately 87% water (in the material pores). The macroporous cryogel composite material, composed of live bacteria, has pore sizes in the range of 20-150 µm (confirmed by SEM and Laser Scanning Confocal Microscopy). The enzymatic activity of bacteria within the cryogel structure and the effect of freezing on the viability of the cross-linked cells was estimated by MTT assay. Cryogels based on Pseudomonas mendocina, Rhodococcus koreensis and Acinetobacter radioresistens were exploited for the effective bioremediation of phenol and m-cresol, and to a lesser extent 2-chlorophenol and 4-chlorophenol, utilising these phenolic contaminants in water as their only source of carbon. For evaluation of treatment scalability the bioreactors were prepared in plastic "Kaldnes" carriers to improve their mechanical properties and allow application in batch or fluidised bed water treatment modes.


Asunto(s)
Criogeles , Purificación del Agua , Biodegradación Ambiental , Reactores Biológicos , Fenol
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