UV-induced fingerprint spectroscopy (UV-IFS), a new tool in a toolbox of analytical methods, is a powerful technique registering molecule-specific changes of fluorescence induced by UV irradiation. Analysis of fluorescence spectra of a sample prior and after UV irradiation enables an identification of a sample of a drug or pharmaceutics based on a comparison with signals of known standards. Moreover, UV-IFS uncovers the presence of undesired contaminations or intentional changes of the composition. Herein, we employ UV-IFS for qualitative as well as quantitative analysis of common medicines including analgesic/antipyretic (Acetaminophen), antihistamines (Loratadine and Desloratadine), and phosphodiesterase type 5 inhibitors (Tadalafil and Sildenafil citrate). UV irradiation (λem = 254 nm) for 2 - 10 min induced significant changes of fluorescence of the studied samples and according to the unique patterns, the quality and quantity were evaluated. Limits of detection for individual active ingredients were calculated as follows: Acetaminophen = 0.1 μg·mL-1, Loratadine = 0.1 μg·mL-1, Desloratadine = 0.01 μg·mL-1, Tadalafil = 0.04 μg·mL-1 and Sildenafil = 0.2 μg·mL-1. Moreover, genuine and fake CIALIS, VIAGRA and KAMAGRA tablets were reliably identified.
- MeSH
- loratadin * MeSH
- paracetamol * MeSH
- sildenafil citrát MeSH
- spektrální analýza MeSH
- tablety MeSH
- tadalafil MeSH
- Publikační typ
- časopisecké články MeSH
Synthesis of RNA nucleobases from formamide is one of the recurring topics of prebiotic chemistry research. Earlier reports suggest that thymine, the substitute for uracil in DNA, may also be synthesized from formamide in the presence of catalysts enabling conversion of formamide to formaldehyde. In the current paper, we show that to a lesser extent conversion of uracil to thymine may occur even in the absence of catalysts. This is enabled by the presence of formic acid in the reaction mixture that forms as the hydrolysis product of formamide. Under the reaction conditions of our study, the disproportionation of formic acid may produce formaldehyde that hydroxymethylates uracil in the first step of the conversion process. The experiments are supplemented by quantum chemical modeling of the reaction pathway, supporting the plausibility of the mechanism suggested by Saladino and coworkers.
To ensure food safety and to prevent unnecessary foodborne complications this study reports fast, fully automated process for histamine determination. This method is based on magnetic separation of histamine with magnetic particles and quantification by the fluorescence intensity change of MSA modified CdSe Quantum dots. Formation of Fe2O3 particles was followed by adsorption of TiO2 on their surface. Magnetism of developed probe enabled rapid histamine isolation prior to its fluorescence detection. Quantum dots (QDs) of approx. 3 nm were prepared via facile UV irradiation. The fluorescence intensity of CdSe QDs was enhanced upon mixing with magnetically separated histamine, in concentration-dependent manner, with a detection limit of 1.6 μM. The linear calibration curve ranged between 0.07 and 4.5 mM histamine with a low LOD and LOQ of 1.6 μM and 6 μM. The detection efficiency of the method was confirmed by ion exchange chromatography. Moreover, the specificity of the sensor was evaluated and no cross-reactivity from nontarget analytes was observed. This method was successfully applied for the direct analysis of histamine in white wine providing detection limit much lower than the histamine maximum levels established by EU regulation in food samples. The recovery rate was excellent, ranging from 84 to 100% with an RSD of less than 4.0%. The main advantage of the proposed method is full automation of the analytical procedure that reduces the time and cost of the analysis, solvent consumption and sample manipulation, enabling routine analysis of large numbers of samples for histamine and highly accurate and precise results.
- MeSH
- fluorescence MeSH
- fluorescenční barviva chemie MeSH
- fluorescenční spektrometrie metody MeSH
- histamin analýza MeSH
- kontaminace potravin analýza MeSH
- kovové nanočástice chemie MeSH
- kvantové tečky chemie MeSH
- limita detekce MeSH
- magnetické jevy MeSH
- silany chemie MeSH
- sloučeniny kadmia chemie MeSH
- telur chemie MeSH
- titan chemie MeSH
- víno analýza MeSH
- železité sloučeniny chemie MeSH
- Publikační typ
- časopisecké články MeSH
Sparsely tested group of platinum nanoparticles (PtNPs) may have a comparable effect as complex platinum compounds. The aim of this study was to observe the effect of PtNPs in in vitro amplification of DNA fragment of phage λ, on the bacterial cultures (Staphylococcus aureus), human foreskin fibroblasts and erythrocytes. In vitro synthesized PtNPs were characterized by dynamic light scattering (PtNPs size range 4.8-11.7 nm), zeta potential measurements (-15 mV at pH 7.4), X-ray fluorescence, UV/vis spectrophotometry and atomic absorption spectrometry. The PtNPs inhibited the DNA replication and affected the secondary structure of DNA at higher concentrations, which was confirmed by polymerase chain reaction, DNA sequencing and DNA denaturation experiments. Further, cisplatin (CisPt), as traditional chemotherapy agent, was used in all parallel experiments. Moreover, the encapsulation of PtNPs in liposomes (LipoPtNPs) caused an approximately 2.4x higher of DNA damage in comparison with CisPt, LipoCisPt and PtNPs. The encapsulation of PtNPs in liposomes also increased their antibacterial, cytostatic and cytotoxic effect, which was determined by the method of growth curves on S. aureus and HFF cells. In addition, both the bare and encapsulated PtNPs caused lower oxidative stress (determined by GSH/GSSG ratio) in the human erythrocytes compared to the bare and encapsulated CisPt. CisPt was used in all parallel experiments as traditional chemotherapy agent.
- MeSH
- buněčné linie MeSH
- erytrocyty účinky léků MeSH
- fibroblasty účinky léků MeSH
- kovové nanočástice škodlivé účinky chemie MeSH
- kultivované buňky MeSH
- lidé MeSH
- oxidační stres MeSH
- platina škodlivé účinky chemie MeSH
- poškození DNA * MeSH
- replikace DNA * MeSH
- Staphylococcus aureus účinky léků genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Nanomaterials in agriculture are becoming popular due to the impressive advantages of these particles. However, their bioavailability and toxicity are key features for their massive employment. Herein, we comprehensively summarize the latest findings on the phytotoxicity of nanomaterial products based on essential metals used in plant protection. The metal nanoparticles (NPs) synthesized from essential metals belong to the most commonly manufactured types of nanomaterials since they have unique physical and chemical properties and are used in agricultural and biotechnological applications, which are discussed. The paper discusses the interactions of nanomaterials and vascular plants, which are the subject of intensive research because plants closely interact with soil, water, and atmosphere; they are also part of the food chain. Regarding the accumulation of NPs in the plant body, their quantification and localization is still very unclear and further research in this area is necessary.
Peptide-peptide interactions are crucial in the living cell as they lead to the formation of the numerous types of complexes. In this study, synthetic peptides containing 11 of cysteines (α-domain of metallothionein (MT)) and sialic acid binding region (130-loop of hemagglutinin (HA)) were employed. The aim of the experiment was studying the interactions between MT and HA-derived peptides. For this purpose, fragments were tagged with cysteines at C-terminal part to serve as ligand sites for PbS and CuS quantum dots (QDs), and therefore these conjugates can be traced and quantified during wide spectrum of methods. As a platform for interaction, γ-Fe2O3 paramagnetic particles modified with tetraethyl orthosilicate and (3-aminopropyl)triethoxysilane (hydrodynamic diameter 30-40 nm) were utilized and MT/HA interactions were examined using multi-instrumental approach including electrochemistry, electrophoretic methods, and MALDI-TOF/TOF mass spectrometry. It was found that peptides enter mutual creation of complexes, which are based on some of nonbonded interactions. The higher willingness to interact was observed in MT-derived peptides toward immobilized HA. Finally, we designed and manufactured flow-through electrochemical 3D printed device (reservoir volume 150 μL) and utilized it for automated analysis of the HA/MT metal labels. Under the optimal conditions, (deposition time and flow rate 80 s and 1.6 mL/min for CuS and 120 s and 1.6 mL/min PbS, respectively), the results of peptide-conjugated QDs were comparable with atomic absorption spectrometry.
Urinary metabolomic profiles have recently drawn a lot of attention owing to a debate regarding their possible role as potential clinical markers for prostate cancer. As was shown, amino acid metabolism in cancer patients differs from that in healthy people, and it can be thus utilized in early diagnostics. In this study, we monitored the behavior of potential noninvasive biomarker for prostate carcinoma, sarcosine, involved in the folate metabolism and DNA methylation processes, linked to the progression of prostate carcinoma. To obtain the maximum amount of information, the biochemical parameters (total protein, creatinine, ions, conductivity) were determined using spectrophotometry and electrochemistry. All results were subjected to statistical processing for revealing different correlations between the studied parameters. These metabolites were observed in the urine obtained from healthy subjects and influence of storage conditions (freezing and thawing) on the concentration of addition of sarcosine was monitored.
- MeSH
- časové faktory MeSH
- chromatografie iontoměničová * statistika a číselné údaje MeSH
- elektrochemické techniky statistika a číselné údaje MeSH
- lidé MeSH
- metabolomika MeSH
- nádorové biomarkery metabolismus moč MeSH
- nádory prostaty metabolismus moč MeSH
- odběr biologického vzorku * metody MeSH
- sarkosin * metabolismus moč MeSH
- teplota MeSH
- termodynamika MeSH
- zmrazování MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- hodnotící studie MeSH
- práce podpořená grantem MeSH
- MeSH
- nanotechnologie MeSH
- vědy o Zemi MeSH
- Publikační typ
- práce podpořená grantem MeSH
- zprávy 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
- lékové transportní systémy * 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
- 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
- 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
- protinádorové látky chemie terapeutické užití MeSH
- spektrofotometrie atomová MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
