Surgery is an efficient way to treat localized prostate cancer (PCa), however, it is challenging to demarcate rapidly and accurately the tumor boundary intraoperatively, as existing tumor detection methods are seldom performed in real-time. To overcome those limitations, we develop a fluorescent molecular rotor that specifically targets the prostate-specific membrane antigen (PSMA), an established marker for PCa. The probes have picomolar affinity (IC50 = 63-118 pM) for PSMA and generate virtually instantaneous onset of robust fluorescent signal proportional to the concentration of the PSMA-probe complex. In vitro and ex vivo experiments using PCa cell lines and clinical samples, respectively, indicate the utility of the probe for biomedical applications, including real-time monitoring of endocytosis and tumor staging. Experiments performed in a PCa xenograft model reveal suitability of the probe for imaging applications in vivo.
- MeSH
- antigeny povrchové chemie metabolismus MeSH
- buňky PC-3 MeSH
- endocytóza MeSH
- fluorescenční spektrometrie metody MeSH
- glutamátkarboxypeptidasa II chemie metabolismus MeSH
- lidé MeSH
- molekulární modely MeSH
- molekulární sondy chemie metabolismus MeSH
- myši inbrední BALB C MeSH
- myši nahé MeSH
- nádorové buněčné linie MeSH
- nádory prostaty diagnóza metabolismus MeSH
- optické zobrazování metody MeSH
- proteinové domény MeSH
- transplantace heterologní MeSH
- vazba proteinů MeSH
- vazebná místa MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
At present, nuclear condensation and fragmentation have been estimated also using Hoechst probes in fluorescence microscopy and flow cytometry. However, none of the methods used the Hoechst probes for quantitative spectrofluorometric assessment. Therefore, the aim of the present study was to develop a spectrofluorometric assay for detection of nuclear condensation and fragmentation in the intact cells. We used human hepatoma HepG2 and renal HK-2 cells cultured in 96-well plates treated with potent apoptotic inducers (i.e. cisplatin, staurosporine, camptothecin) for 6-48 h. Afterwards, the cells were incubated with Hoechst 33258 (2 µg/mL) and the increase of fluorescence after binding of the dye to DNA was measured. The developed spectrofluorometric assay was capable to detect nuclear changes caused by all tested apoptotic inducers. Then, we compared the outcomes of the spectrofluorometric assay with other methods detecting cell impairment and apoptosis (i.e. WST-1 and glutathione tests, TUNEL, DNA ladder, caspase activity, PARP-1 and JNKs expressions). We found that our developed spectrofluorometric assay provided results of the same sensitivity as the TUNEL assay but with the advantages of being fast processing, low-cost and a high throughput. Because nuclear condensation and fragmentation can be typical markers of cell death, especially in apoptosis, we suppose that the spectrofluorometric assay could become a routinely used method for characterizing cell death processes.
- MeSH
- antitumorózní látky farmakologie MeSH
- apoptóza účinky léků MeSH
- bisbenzimidazol chemie MeSH
- buněčná smrt účinky léků MeSH
- buněčné jádro účinky léků metabolismus MeSH
- buněčné linie MeSH
- buňky Hep G2 MeSH
- cisplatina farmakologie MeSH
- fluorescenční mikroskopie metody MeSH
- fluorescenční spektrometrie metody MeSH
- fragmentace DNA účinky léků MeSH
- kamptothecin farmakologie MeSH
- lidé MeSH
- průtoková cytometrie metody MeSH
- reprodukovatelnost výsledků MeSH
- staurosporin farmakologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The interactions of epoxiconazole and prothioconazole with human serum albumin and bovine serum albumin were investigated using spectroscopic methods complemented with molecular modeling. Spectroscopic techniques showed the formation of pesticide/serum albumin complexes with the static type as the dominant mechanism. The association constants ranged from 3.80 × 104-6.45 × 105 L/mol depending on the pesticide molecule (epoxiconazole, prothioconazole) and albumin type (human or bovine serum albumin). The calculated thermodynamic parameters revealed that the binding of pesticides into serum albumin macromolecules mainly depended on hydrogen bonds and van der Waals interactions. Synchronous fluorescence spectroscopy and the competitive experiments method showed that pesticides bind to subdomain IIA, near tryptophan; in the case of bovine serum albumin also on the macromolecule surface. Concerning prothioconazole, we observed the existence of an additional binding site at the junction of domains I and III of serum albumin macromolecules. These observations were corroborated well by molecular modeling predictions. The conformation changes in secondary structure were characterized by circular dichroism, three-dimensional fluorescence, and UV/VIS absorption methods.
- MeSH
- cirkulární dichroismus metody MeSH
- epoxidové sloučeniny chemie MeSH
- fluorescenční spektrometrie metody MeSH
- hydrofobní a hydrofilní interakce MeSH
- lidé MeSH
- lidský sérový albumin chemie MeSH
- pesticidy chemie MeSH
- sekundární struktura proteinů MeSH
- sérový albumin hovězí chemie MeSH
- simulace molekulového dockingu metody MeSH
- skot MeSH
- statická elektřina MeSH
- teplota MeSH
- triazoly chemie MeSH
- vazba proteinů MeSH
- vazebná místa MeSH
- vodíková vazba MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- skot MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The effects of combining naturally evolved photosynthetic pigment-protein complexes with inorganic functional materials, especially plasmonically active metallic nanostructures, have been a widely studied topic in the last few decades. Besides other applications, it seems to be reasonable using such hybrid systems for designing future biomimetic solar cells. In this paper, we describe selected results that point out to various aspects of the interactions between photosynthetic complexes and plasmonic excitations in Silver Island Films (SIFs). In addition to simple light-harvesting complexes, like peridinin-chlorophyll-protein (PCP) or the Fenna-Matthews-Olson (FMO) complex, we also discuss the properties of large, photosynthetic reaction centers (RCs) and Photosystem I (PSI)-both prokaryotic PSI core complexes and eukaryotic PSI supercomplexes with attached antenna clusters (PSI-LHCI)-deposited on SIF substrates.
- MeSH
- chlorofyl a metabolismus MeSH
- fluorescenční spektrometrie metody MeSH
- formaldehyd chemie MeSH
- fotosyntéza * MeSH
- fotosystém I - proteinový komplex metabolismus MeSH
- glukosa chemie MeSH
- karotenoidy metabolismus MeSH
- nanostruktury chemie ultrastruktura MeSH
- stříbro chemie MeSH
- světlosběrné proteinové komplexy metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
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
Photosynthetic eukaryotes whose cells harbor plastids originating from secondary endosymbiosis of a red alga include species of major ecological and economic importance. Since utilization of solar energy relies on the efficient light-harvesting, one of the critical factors for the success of the red lineage in a range of environments is to be found in the adaptability of the light-harvesting machinery, formed by the proteins of the light-harvesting complex (LHC) family. A number of species are known to employ mainly a unique class of LHC containing red-shifted chlorophyll a (Chl a) forms absorbing above 690 nm. This appears to be an adaptation to shaded habitats. Here we present a detailed investigation of excitation energy flow in the red-shifted light-harvesting antenna of eustigmatophyte Trachydiscus minutus using time-resolved fluorescence and ultrafast transient absorption measurements. The main carotenoid in the complex is violaxanthin, hence this LHC is labeled the red-violaxanthin-Chl a protein, rVCP. Both the carotenoid-to-Chl a energy transfer and excitation dynamics within the Chl a manifold were studied and compared to the related antenna complex, VCP, that lacks the red-Chl a. Two spectrally defined carotenoid pools were identified in the red antenna, contributing to energy transfer to Chl a, mostly via S2 and hot S1 states. Also, Chl a triplet quenching by carotenoids is documented. Two separate pools of red-shifted Chl a were resolved, one is likely formed by excitonically coupled Chl a molecules. The structural implications of these observations are discussed.
- MeSH
- chlorofyl a * MeSH
- Chlorophyta fyziologie MeSH
- fluorescenční spektrometrie metody MeSH
- Heterokontophyta fyziologie MeSH
- plastidy MeSH
- přenos energie fyziologie MeSH
- Rhodophyta fyziologie MeSH
- světlosběrné proteinové komplexy chemie MeSH
- xanthofyly MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
A rapid procedure for the determination of 2-aminoisobutyric acid in enzalutamide bulk drug substance based on hydrophilic interaction chromatography with fluorescence detection was developed. Fluorescence detection after postcolumn derivatization with o-phthaldialdehyde/2-mercaptoethanol was carried out at excitation and emission wavelength of 345 nm and 450 nm, respectively. The postcolumn reaction conditions such as reaction temperature, mobile phase and derivatization reagent flow rate and the reagents concentrations were studied and optimized due to steric hindrance of amino group of 2-aminoisobutyric acid. The derivatization reaction was applied for the hydrophilic interaction chromatography method which was based on COSMOSIL HILIC column with a mobile phase consisting of a mixture of 25 mmol/L acetic acid adjusted to pH 5.5 (using 1 mol/L potassium hydroxide) and acetonitrile using an isocratic elution (28:72, ν/ν). The benefit of the reported approach consists in a simple sample pretreatment and a quick and sensitive hydrophilic interaction chromatography method. The developed method was validated in terms of linearity, limit of detection, limit of quantification, accuracy, precision and selectivity according to the International Conference on Harmonisation guidelines. The developed method was demonstrated to be applied for the analysis of 2-AIBA in routine quality control evaluation of commercial samples of enzalutamide bulk drug substance.
- MeSH
- acetonitrily chemie MeSH
- antagonisté androgenních receptorů analýza chemie MeSH
- fenylthiohydantoin analogy a deriváty analýza chemie MeSH
- fluorescenční spektrometrie přístrojové vybavení metody MeSH
- hydrofobní a hydrofilní interakce MeSH
- kontaminace léku prevence a kontrola MeSH
- kyseliny aminoisomáselné analýza MeSH
- limita detekce MeSH
- merkaptoethanol chemie MeSH
- o-ftalaldehyd chemie MeSH
- reprodukovatelnost výsledků MeSH
- řízení kvality * MeSH
- vysokoúčinná kapalinová chromatografie přístrojové vybavení metody MeSH
- Publikační typ
- časopisecké články MeSH
- validační studie MeSH
Due to the close relationship between carcinogenesis and human papillomavirus (HPV), and since they are transmitted via huge number of asymptomatic carriers, the detection of HPV is really needed to reduce the risk of developing cancer. According to the best of our knowledge, our study provides the very first method for one-step detection of viral infection and if it has initiated the subsequent cancer proliferation. The proposed novel nanosystem consists of magnetic glass particles (MGPs), which were attached with DNA probe on their surface to hybridize with target DNAs. The MGP-probe-DNA hybrid was finally conjugated with CdTe/ZnSe core/shell quantum dots (QDs). The proposed detection system is based on a novel mechanism in which the MGPs separate out the target DNAs from different biological samples using external magnetic field for better and clear detection and the QDs give different fluorescent maxima for different target DNAs due to their ability to interact differently with different nucleotides. Firstly, the method was optimized using HPV genes cloned into synthetic plasmids. Then it was applied directly on the samples from normal and cancerous cells. After that, the real hospital samples of head and neck squamous cell carcinoma (HNSCC) with or without the infection of HPV were also analyzed. Our novel nano-system is proved successful in detecting and distinguishing between the patients suffering by HPV infection with or without subsequent cancer having detection limit estimated as 1.0 x 109 (GEq/mL). The proposed methodology is faster and cost-effective, which can be applied at the clinical level to help the doctors to decide the strategy of medication that may save the life of the patients with an early treatment.
- MeSH
- biosenzitivní techniky metody MeSH
- dlaždicobuněčné karcinomy hlavy a krku virologie MeSH
- DNA sondy chemie genetika MeSH
- DNA virů krev chemie genetika MeSH
- dospělí MeSH
- fluorescenční mikroskopie metody MeSH
- fluorescenční spektrometrie metody MeSH
- hybridizace nukleových kyselin MeSH
- infekce papilomavirem diagnóza MeSH
- kvantové tečky chemie MeSH
- lidé MeSH
- limita detekce MeSH
- magnetické jevy MeSH
- nádorové buněčné linie MeSH
- Papillomaviridae chemie MeSH
- senioři MeSH
- sklo chemie MeSH
- sloučeniny kadmia chemie MeSH
- telur chemie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
In this article, optimization of BGE for simultaneous separation of inorganic ions, organic acids, and glutathione using dual C4 D-LIF detection in capillary electrophoresis is presented. The optimized BGE consisted of 30 mM 2-[4-(2-hydroxyethyl)piperazin-1-yl]ethanesulfonic acid, 15 mM 2-amino-2-hydroxymethyl-propane-1,3-diol, and 2 mM 18-crown-6 at pH 7.2 and allowed simultaneous separation of ten inorganic anions and cations, three organic acids and glutathione in 20 min. The samples were injected hydrodynamically from both capillary ends using the double-opposite end injection principle. Sensitive detection of anions, cations, and organic acids with micromolar LODs using C4 D and simultaneously glutathione with nanomolar LODs using LIF was achieved in a single run. The developed BGE may be useful in analyses of biological samples containing analytes with differing concentrations of several orders of magnitude that is not possible with single detection mode.
- MeSH
- dechové testy metody MeSH
- design vybavení MeSH
- elektrická vodivost MeSH
- elektroforéza kapilární metody MeSH
- fluorescenční spektrometrie metody MeSH
- glutathion analýza izolace a purifikace MeSH
- ionty analýza izolace a purifikace MeSH
- kyseliny karboxylové analýza izolace a purifikace MeSH
- lidé MeSH
- limita detekce MeSH
- lineární modely MeSH
- reprodukovatelnost výsledků MeSH
- slzy chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The spatiotemporal sensing of specific cationic and anionic species is crucial for understanding the processes occurring in living systems. Herein, we developed new fluorescence sensors derived from tetrapyrazinoporphyrazines (TPyzPzs) with a recognition moiety that consists of an aza-crown and supporting substituents. Their sensitivity and selectivity were compared by fluorescence titration experiments with the properties of known TPyzPzs (with either one aza-crown moiety or two of these moieties in a tweezer arrangement). Method of standard addition was employed for analyte quantification in saliva. For K+ recognition, the new derivatives had comparable or larger association constants with larger fluorescence enhancement factors compared to that with one aza-crown. Their fluorescence quantum yields in the ON state were 18× higher than that of TPyzPzs with a tweezer arrangement. Importantly, the sensitivity toward cations was strongly dependent on counteranions and increased as follows: NO3- < Br- < CF3SO3- < ClO4- ≪ SCN-. This trend resembles the chaotropic ability expressed by the Hofmeister series. The high selectivity toward KSCN was explained by synergic association of both K+ and SCN- with TPyzPz sensors. The sensing of SCN- was further exploited in a proof of concept study to quantify SCN- levels in the saliva of a smoker and to demonstrate the sensing ability of TPyzPzs under in vitro conditions.
- MeSH
- crown ethery chemická syntéza chemie MeSH
- draslík analýza MeSH
- fluorescence MeSH
- fluorescenční barviva chemická syntéza chemie MeSH
- fluorescenční mikroskopie metody MeSH
- fluorescenční spektrometrie metody MeSH
- HeLa buňky MeSH
- kuřáci MeSH
- lidé MeSH
- limita detekce MeSH
- metaloporfyriny chemická syntéza chemie MeSH
- sliny chemie MeSH
- thiokyanatany analýza MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
