The removal of selenium from superficial and waste water is a worldwide problem. The maximum limit according to the World Health Organization (WHO) for the selenium in the water is set at a concentration of 10 μg/L. Carbon based adsorbents have attracted much attention and recently demonstrated promising performance in removal of selenium. In this work, several materials (iron oxide based microparticles and graphene oxides materials) and their composites were prepared to remove Se(IV) from water. The graphene oxides were prepared according to the simplified Hummer's method. In addition, the effect of pH, contact time and initial Se(IV) concentration was tested. An electrochemical method such as the differential pulse cathodic stripping voltammetry was used to determine the residual selenium concentration. From the experimental data, Langmuir adsorption model was used to calculate the maximum adsorption capacity. Graphene oxide particles modified by iron oxide based microparticles was the most promising material for the removal of Se(IV) from its aqueous solution at pH 2.0. Its adsorption efficiency reached more than 90% for a solution with given Se(IV) concentration, meanwhile its maximal recorded adsorption capacity was 18.69 mg/g.
- MeSH
- adsorpce MeSH
- časové faktory MeSH
- chemické látky znečišťující vodu izolace a purifikace MeSH
- elektrochemické techniky metody MeSH
- elektrody MeSH
- grafit chemie MeSH
- koncentrace vodíkových iontů MeSH
- mikrosféry MeSH
- roztoky MeSH
- selen izolace a purifikace MeSH
- statická elektřina MeSH
- teplota MeSH
- velikost částic MeSH
- Publikační typ
- časopisecké články MeSH
Liposome-based drug delivery systems hold great potential for cancer therapy. The aim of this study was to design a nanodevice for targeted anchoring of liposomes (with and without cholesterol) with encapsulated anticancer drugs and antisense N-myc gene oligonucleotide attached to its surface. To meet this main aim, liposomes with encapsulated doxorubicin, ellipticine and etoposide were prepared. They were further characterized by measuring their fluorescence intensity, whereas the encapsulation efficiency was estimated to be 16%. The hybridization process of individual oligonucleotides forming the nanoconstruct was investigated spectrophotometrically and electrochemically. The concentrations of ellipticine, doxorubicin and etoposide attached to the nanoconstruct in gold nanoparticle-modified liposomes were found to be 14, 5 and 2 µg·mL(-1), respectively. The study succeeded in demonstrating that liposomes are suitable for the transport of anticancer drugs and the antisense oligonucleotide, which can block the expression of the N-myc gene.
- MeSH
- antisense DNA chemie terapeutické užití MeSH
- doxorubicin chemie terapeutické užití MeSH
- elipticiny chemie terapeutické užití MeSH
- etoposid chemie terapeutické užití MeSH
- fluorescence MeSH
- lidé MeSH
- liposomy chemie terapeutické užití MeSH
- magnetické nanočástice chemie terapeutické užití MeSH
- nádory farmakoterapie MeSH
- protoonkogen n-myc antagonisté a inhibitory genetika MeSH
- systémy cílené aplikace léků * MeSH
- zlato chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Arsenic compounds belong to the most controversial agents concerning human health. Arsenic (As) is considered as a top environmental element influencing human health due to its adverse effects including cancer, diabetes, cardiovascular disease, and reproductive or developmental problems. Despite the proven mutagenic, teratogenic and carcinogenic effects, the arsenic compounds are used for centuries to treat infectious diseases. In our work, we focused on studying of interactions of As(III) and/or As(V) with DNA. Interactions between arsenic ions and DNA were monitored by UV/vis spectrophotometry by measuring absorption and fluorescence spectra, atomic absorption spectrometry, electrochemical measurements (square wave voltammetry) and agarose gel electrophoresis. Using these methods, we observed a stable structure of DNA with As(III) within the concentration range 0.4-6.25 μg mL(-1). Higher As(III) concentration caused degradation of DNA. However, similar effects were not observed for As(V).
- MeSH
- antitumorózní látky chemie terapeutické užití MeSH
- arsen škodlivé účinky terapeutické užití MeSH
- DNA chemie účinky léků genetika MeSH
- fragmentace DNA účinky léků MeSH
- infekční nemoci farmakoterapie patologie MeSH
- ionty chemie MeSH
- lidé MeSH
- metalothionein chemie genetika MeSH
- spektrofotometrie atomová MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
