Tripolyphosphate
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The use of nanoparticles as a delivery system for a specific antigen could solve many limitations of mucosal vaccine applications, such as low immunogenicity, or antigen protection and stabilization. In this study, we tested the ability of nasally administered chitosan nanoparticles loaded with glycoprotein B of murine cytomegalovirus to induce an immune response in an animal model. The choice of chitosan nanoparticle type was made by in vitro evaluation of sorption efficiency and antigen release. Three types of chitosan nanoparticles were prepared: crosslinked with tripolyphosphate, coated with hyaluronic acid, and in complex with polycaprolactone. The hydrodynamic size of the nanoparticles by dynamic light scattering, zeta potential, Fourier transform infrared spectroscopy, scanning electron microscopy, stability, loading efficiency, and release kinetics with ovalbumin were evaluated. Balb/c mice were immunized intranasally using the three-dose protocol with nanoparticles, gB, and adjuvants Poly(I:C) and CpG ODN. Subsequently, the humoral and cell-mediated antigen-specific immune response was determined. On the basis of the properties of the tested nanoparticles, the cross-linked nanoparticles were considered optimal for further investigation. The results show that nanoparticles with Poly(I:C) and with gB alone raised IgG antibody levels above the negative control. In the case of mucosal IgA, only gB alone weakly induced the production of IgA antibodies compared to saline-immunized mice. The number of activated cells increased slightly in mice immunized with nanoparticles and gB compared to those immunized with gB alone or to negative control. The results demonstrated that chitosan nanoparticles could have potential in the development of mucosal vaccines.
- MeSH
- adjuvancia imunologická MeSH
- aplikace intranazální MeSH
- chitosan * chemie MeSH
- glykoproteiny MeSH
- imunizace MeSH
- imunoglobulin A MeSH
- Muromegalovirus * MeSH
- myši inbrední BALB C MeSH
- myši MeSH
- nanočástice * chemie MeSH
- slizniční imunita MeSH
- vakcíny * MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
In this work, levofloxacin (LVX), a third-generation fluoroquinolone antibiotic, is encapsulated within amphiphilic polymeric nanoparticles of a chitosan-g-poly(methyl methacrylate) produced by self-assembly and physically stabilized by ionotropic crosslinking with sodium tripolyphosphate. Non-crosslinked nanoparticles display a size of 29 nm and a zeta-potential of +36 mV, while the crosslinked counterparts display 45 nm and +24 mV, respectively. The cell compatibility, uptake, and intracellular trafficking are characterized in the murine alveolar macrophage cell line MH-S and the human bronchial epithelial cell line BEAS-2B in vitro. Internalization events are detected after 10 min and the uptake is inhibited by several endocytosis inhibitors, indicating the involvement of complex endocytic pathways. In addition, the nanoparticles are detected in the lysosomal compartment. Then, the antibacterial efficacy of LVX-loaded nanoformulations (50% w/w drug content) is assessed in MH-S and BEAS-2B cells infected with Staphylococcus aureus and the bacterial burden is decreased by 49% and 46%, respectively. In contrast, free LVX leads to a decrease of 8% and 5%, respectively, in the same infected cell lines. Finally, intravenous injection to a zebrafish larval model shows that the nanoparticles accumulate in macrophages and endothelium and demonstrate the promise of these amphiphilic nanoparticles to target intracellular infections.
- MeSH
- antibakteriální látky farmakologie MeSH
- chitosan * MeSH
- dánio pruhované MeSH
- lidé MeSH
- makrofágy metabolismus MeSH
- myši MeSH
- nanočástice * MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
A glycoside hydrolase family 5 β-mannanase-encoding gene was cloned from Bacillus sp. HJ14 isolated from saline soil in Heijing town. Coding sequence of mature protein (without the predicted signal peptide from M1 to A30) was successfully expressed in Escherichia coli BL21 (DE3). Purified recombinant mannanase (rMan5HJ14) exhibited optimal activity at pH 6.5 and 65 °C. The enzyme showed good salt tolerance, retaining more than 56 % β-mannanase activity at 3.0-30.0 % (w/v) NaCl and more than 94 % of the initial activity after incubation with 3.0-30.0 % (w/v) NaCl at 37 °C for 60 min. Almost no mannanase activity was lost after incubation of rMan5HJ14 with trypsin, proteinase K, and Alcalase at 37 °C for 60 min. Surfactants and chelating agents, namely SDS, CTAB, Tween 80, Triton X-100, EDTA, and sodium tripolyphosphate, showed little or no effect (retaining >82.4 % activity) on enzymatic activity. Liquid detergents, namely Tupperware, Walch, Bluemoon, Tide, and OMO, also showed little or no effect (retaining >72.4 % activity) on enzymatic activity at 0.5-2.0 % (v/v). The enzyme further presents a high proportion (11.97 %) of acidic amino acid residues (D and E), which may affect the SDS and NaCl tolerance of the enzyme. Together, the mannanase may be an alternative for potential use in liquid detergent industry.
- MeSH
- aktivace enzymů účinky léků MeSH
- Bacillus účinky léků genetika metabolismus MeSH
- beta-mannosidasa chemie genetika izolace a purifikace metabolismus MeSH
- chlorid sodný farmakologie MeSH
- detergenty farmakologie MeSH
- endopeptidasy metabolismus MeSH
- exprese genu MeSH
- genom bakteriální MeSH
- hydrolýza MeSH
- ionty MeSH
- kovy MeSH
- povrchově aktivní látky farmakologie MeSH
- rekombinantní proteiny MeSH
- sekvence aminokyselin MeSH
- sekvenční analýza DNA MeSH
- stabilita enzymů účinky léků MeSH
- tolerance k soli * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Annual epidemics of influenza cause death of hundreds of thousands people and they also have a significant economic impact. Hence, a need for fast and cheap influenza diagnostic method is arising. The conventional methods for an isolation of the viruses are time-consuming and require expensive instrumentation as well as trained personnel. In this study, we modified the surface of nanomaghemite (γ-Fe2 O3 ) paramagnetic core with tetraethyl orthosilicate and (3-aminopropyl)triethoxysilane and the resulting particles were utilized for the isolation of H7N7 influenza virions. Consequently, we designed γ-Fe2 O3 paramagnetic core modified with calcium tripolyphosphate which was employed for the isolation of viral nucleic acid after virion's lysis. Both of these procedures can be performed rapidly in less than 10 min and, in combination with the RT-PCR, the whole influenza detection can be shortened to few hours. Moreover, the whole protocol could be easily automated and/or miniaturized, and thus can serve as a basis for use in a lab-on-a-chip device. We assume that magnetic isolation is an exceptional procedure which can significantly accelerate the diagnostic possibilities of a broad spectrum of diseases.
- MeSH
- chromatografie iontoměničová MeSH
- elektroforéza v polyakrylamidovém gelu MeSH
- kuřecí embryo MeSH
- polymerázová řetězová reakce metody MeSH
- reverzní transkripce MeSH
- virion izolace a purifikace MeSH
- virus chřipky A, podtyp H7N7 izolace a purifikace MeSH
- zvířata MeSH
- Check Tag
- kuřecí embryo MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Magnetic isolation of biological targets is in major demand in the biotechnology industry today. This study considers the interaction of four surface-modified magnetic micro- and nanoparticles with selected DNA fragments. Different surface modifications of nanomaghemite precursors were investigated: MAN37 (silica-coated), MAN127 (polyvinylpyrrolidone-coated), MAN158 (phosphate-coated), and MAN164 (tripolyphosphate-coated). All particles were positive polycharged agglomerated monodispersed systems. Mean particle sizes were 0.48, 2.97, 2.93, and 3.67 μm for MAN37, MAN127, MAN164, and MAN158, respectively. DNA fragments exhibited negative zeta potential of -0.22 mV under binding conditions (high ionic strength, low pH, and dehydration). A decrease in zeta potential of particles upon exposure to DNA was observed with exception of MAN158 particles. The measured particle size of MAN164 particles increased by nearly twofold upon exposure to DNA. Quantitative PCR isolation of DNA with a high retrieval rate was observed by magnetic particles MAN127 and MAN164. Interaction between polycharged magnetic particles and DNA is mediated by various binding mechanisms such as hydrophobic and electrostatic interactions. Future development of DNA isolation technology requires an understanding of the physical and biochemical conditions of this process.
Cílem experimentální studie bylo optimalizovat přípravu mikrosfér z vysokoviskozitního chitosanu metodou vnější iontové gelace a zhodnotit vybrané aspekty jejich přípravy. U mikročástic bez léčiva byla formulační proměnnou koncentrace chitosanových disperzí, procesní proměnnou pak byla poloha přístroje (horizontální vs. vertikální) pro jejich extruzi. Na základě výsledků sféricity a velikosti připravených mikročástic byly vybrány tři koncentrace disperzí, které se použily pro enkapsulaci modelového léčiva 5-aminosalicylové kyseliny (5-ASA) metodou využívající horizontální polohu přístroje pro extruzi, která byla vyhodnocena jako optimální. U mikročástic s léčivem byly sledovanými proměnnými koncentrace chitosanu a složení tvrdícího roztoku (10% tripolyfosfát sodný (TPP) vs. 10% TPP s obsahem léčiva). Bylo zjištěno, že u připravených mikrosfér se s vzrůstající koncentrací chitosanu zvyšoval jejich ekvivalentní průměr, sféricita byla srovnatelná. Vzorky, při jejichž přípravě bylo léčivo přítomno jak v disperzi chitosanu, tak i v tvrdící lázni, měly vyšší obsah léčiva a menší ekvivalentní průměr a vykazovaly rychlejší uvolňování léčiva v podmínkách in vitro v porovnání se vzorky, u kterých bylo léčivo zapracováno pouze do disperze chitosanu. Klíčová slova: mikročástice • vnější iontová gelace • chitosan • formulační a procesní parametry • disoluční profil
The aim of this experimental study was to optimize a preparation of microspheres from high viscosity chitosan by external ion gelation and to evaluate selected aspects of their preparation. For drug-free microparticles, the concentration of chitosan dispersions was chosen as a formulation variable; the position of instrument for a dispersion extrusion (horizontal vs. vertical) was evaluated as a process variable. On the basis of sphericity and equivalent diameter results, three different concentrations of chitosan dispersions were used for 5-aminosalicylic acid (5-ASA) encapsulation with the extrusion instrument in horizontal position, which was considered as the optimal. In consequent drug-loaded microparticle preparation, the influence of the concentration of chitosan dispersions and composition of hardening solution (10% sodium tripolyphosphate (TPP) vs. 10% TPP containing drug) was evaluated. In prepared 5-ASA microspheres it was found that the equivalent diameter increased with increasing chitosan concentration. In the case of sphericity, significant differences were not found. Samples prepared with the drug in both chitosan dispersion and hardening solution had a higher drug content, a smaller equivalent diameter and they showed a faster in vitro drug release in comparison with the samples prepared with the drug in chitosan dispersion only. Keywords: microparticles • external ionic gelation • chitosan • formulation and process parameters • dissolution profile
- Klíčová slova
- mikročástice, disoluční profil, vnější iontová gelace, stereoskopická mikroskopie, tvrdící roztok, bobtnavost,
- MeSH
- chitosan * farmakologie chemie MeSH
- farmaceutická technologie MeSH
- koncentrace vodíkových iontů MeSH
- lékové formy MeSH
- lékové transportní systémy * MeSH
- mesalamin MeSH
- mikroskopie metody MeSH
- nosiče léků * MeSH
- povrchové vlastnosti MeSH
- rozpustnost MeSH
- velikost částic * MeSH
- vztahy mezi strukturou a aktivitou MeSH
