AIM: To evaluate the potential of tumor-targeted nanoprobe, N-(2-hydroxypropyl)methacrylamide copolymer-conjugated zinc protoporphyrin (PZP) for photodynamic therapy (PDT) and tumor imaging. MATERIALS & METHODS: Different tumor models including carcinogen-induced cancer were used, PZP was intravenously injected followed by irradiation with xenon or blue fluorescent light on tumor. RESULTS: One PZP 20 mg/kg (ZnPP equivalent) dose with two or three treatments of light at an intensity of ≥20 J/cm2 caused necrosis and disappearance of most tumors (>70%) in different tumor models. We also confirmed PZP-based tumor imaging in carcinogen-induced breast tumor and colon cancer models. CONCLUSION: These findings support the potential application of PZP as a tumor-selective nanoprobe for PDT as well as tumor imaging, by virtue of the enhanced permeability and retention effect.

• Klíčová slova
• fluorescent nanoprobe, photodynamic therapy, theranostic nanomedicine, tumor imaging, zinc protoporphyrin,
• Publikační typ
• časopisecké články MeSH

To facilitate efficient drug delivery to tumor tissue, several nanomaterials have been designed, with combined diagnostic and therapeutic properties. In this work, we carried out fundamental in vitro and in vivo experiments to assess the labeling efficacy of our novel theranostic nanoprobe, consisting of glycogen conjugated with a red fluorescent probe and gadolinium. Microscopy and resazurin viability assays were used to study cell labeling and cell viability in human metastatic melanoma cell lines. Fluorescence lifetime correlation spectroscopy (FLCS) was done to investigate nanoprobe stability. Magnetic resonance imaging (MRI) was performed to study T₁ relaxivity in vitro, and contrast enhancement in a subcutaneous in vivo tumor model. Efficient cell labeling was demonstrated, while cell viability, cell migration, and cell growth was not affected. FLCS showed that the nanoprobe did not degrade in blood plasma. MRI demonstrated that down to 750 cells/μL of labeled cells in agar phantoms could be detected. In vivo MRI showed that contrast enhancement in tumors was comparable between Omniscan contrast agent and the nanoprobe. In conclusion, we demonstrate for the first time that a non-toxic glycogen-based nanoprobe may effectively visualize tumor cells and tissue, and, in future experiments, we will investigate its therapeutic potential by conjugating therapeutic compounds to the nanoprobe.

• Klíčová slova
• fluorescence lifetime correlation spectroscopy, fluorescence microscopy, high throughput microscopy, magnetic resonance imaging, melanoma brain metastasis, nanoprobe, theranostics, zeta potential,
• MeSH
• barvení a značení MeSH
• cytoplazma metabolismus   MeSH
• fluorescenční spektrometrie MeSH
• glykogen metabolismus   MeSH
• koncentrace vodíkových iontů MeSH
• kontrastní látky chemie   MeSH
• lidé MeSH
• lyzozomy metabolismus   MeSH
• magnetická rezonanční tomografie metody   MeSH
• melanom metabolismus   patologie   MeSH
• molekulární sondy * MeSH
• molekulární zobrazování metody   MeSH
• multimodální zobrazování * MeSH
• nádorové buněčné linie MeSH
• nanotechnologie * MeSH
• pohyb buněk MeSH
• viabilita buněk MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• glykogen MeSH
• kontrastní látky MeSH
• molekulární sondy * MeSH

In the last few years, magnetically labeled cells have been intensively explored, and non-invasive cell tracking and magnetic manipulation methods have been tested in preclinical studies focused on cell transplantation. For clinical applications, it is desirable to know the intracellular pathway of nanoparticles, which can predict their biocompatibility with cells and the long-term imaging properties of labeled cells. Here, we quantified labeling efficiency, localization, and fluorescence properties of Rhodamine derivatized superparamagnetic maghemite nanoparticles (SAMN-R) in mesenchymal stromal cells (MSC). We investigated the stability of SAMN-R in the intracellular space during a long culture (20 days). Analyses were based on advanced confocal microscopy accompanied by atomic absorption spectroscopy (AAS) and magnetic resonance imaging. SAMN-R displayed excellent cellular uptake (24 h of labeling), and no toxicity of SAMN-R labeling was found. 83% of SAMN-R nanoparticles were localized in lysosomes, only 4.8% were found in mitochondria, and no particles were localized in the nucleus. On the basis of the MSC fluorescence measurement every 6 days, we also quantified the continual decrease of SAMN-R fluorescence in the average single MSC during 18 days. An additional set of analyses showed that the intracellular SAMN-R signal decrease was minimally caused by fluorophore degradation or nanoparticles extraction from the cells, main reason is a cell division. The fluorescence of SAMN-R nanoparticles within the cells was detectable minimally for 20 days. These observations indicate that SAMN-R nanoparticles have a potential for application in transplantation medicine.

• Klíčová slova
• Confocal microscopy, Dual contrast agents, Intracellular fluorescent labels, Iron oxide nanoparticles, Mesenchymal stromal cells, Rhodamine, Stem cell tracking,
• MeSH
• dextrany metabolismus   MeSH
• fluorescenční spektrometrie MeSH
• intracelulární prostor metabolismus   MeSH
• lidé MeSH
• magnetické nanočástice chemie   MeSH
• mezenchymální kmenové buňky cytologie   metabolismus   MeSH
• molekulární sondy chemie   metabolismus   MeSH
• molekulární zobrazování metody   MeSH
• rhodaminy chemie   MeSH
• tuková tkáň cytologie   MeSH
• viabilita buněk MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• dextrany MeSH
• ferumoxides MeSH Prohlížeč
• magnetické nanočástice MeSH
• molekulární sondy MeSH
• rhodaminy MeSH

One obstacle to the successful delivery of nanodrugs into solid tumors is the heterogeneity of an enhanced permeability and retention (EPR) effect as a result of occluded or embolized tumor blood vessels. Therefore, the augmentation of the EPR effect is critical for satisfactory anticancer nanomedicine. In this study, we focused on one vascular mediator involved in the EPR effect, carbon monoxide (CO), and utilized two CO generating agents, one is an extrinsic CO donor (SMA/CORM2 micelle) and another is an inducer of endogenous CO generation via heme oxygenase-1 (HO-1) induction that is carried out using pegylated hemin. Both agents generated CO selectively in solid tumors, which resulted in an enhanced EPR effect and a two- to three-folds increased tumor accumulation of nanodrugs. An increase in drug accumulation in the normal tissue did not occur with the treatment of CO generators. In vivo imaging also clearly indicated a more intensified fluorescence of macromolecular nanoprobe in solid tumors when combined with these CO generators. Consequently, the combination of CO generators with anticancer nanodrugs resulted in an increased anticancer effect in the different transplanted solid tumor models. These findings strongly warrant the potential application of these CO generators as EPR enhancers in order to enhance tumor detection and therapy using nanodrugs.

• Klíčová slova
• EPR effect, PDT, carbon monoxide, nanomedicine, nanoprobe,
• Publikační typ
• časopisecké články MeSH

We study the effect of thermal annealing on the electrical properties of the nanoscale p-n heterojunctions based on single n-type ZnO nanorods on p-type GaN substrates. The ZnO nanorods are prepared by chemical bath deposition on both plain GaN substrates and on the substrates locally patterned by focused ion beam lithography. Electrical properties of single nanorod heterojunctions are measured with a nanoprobe in the vacuum chamber of a scanning electron microscope. The focused ion beam lithography provides a uniform nucleation of ZnO, which results in a uniform growth of ZnO nanorods. The specific configuration of the interface between the ZnO nanorods and GaN substrate created by the focused ion beam suppresses the surface leakage current and improves the current-voltage characteristics. Further improvement of the electrical characteristics is achieved by annealing of the structures in nitrogen, which limits the defect-mediated leakage current and increases the carrier injection efficiency.

• Klíčová slova
• ZnO nanorods, annealing, chemical bath deposition, current-voltage characteristics, focused ion beam patterning, nanoprobe in the scanning electron microscope, nanoscale heterojunctions,
• Publikační typ
• časopisecké články MeSH

Herein, an advanced bioconjugation technique to synthesize hybrid polymer-antibody nanoprobes tailored for fluorescent cell barcoding in flow cytometry-based immunophenotyping of leukocytes is applied. A novel approach of attachment combining two fluorescent dyes on the copolymer precursor and its conjugation to antibody is employed to synthesize barcoded nanoprobes of antibody polymer dyes allowing up to six nanoprobes to be resolved in two-dimensional cytometry analysis. The major advantage of these nanoprobes is the construct design in which the selected antibody is labeled with an advanced copolymer bearing two types of fluorophores in different molar ratios. The cells after antibody recognition and binding to the target antigen have a characteristic double fluorescence signal for each nanoprobe providing a unique position on the dot plot, thus allowing antibody-based barcoding of cellular samples in flow cytometry assays. This technique is valuable for cellular assays that require low intersample variability and is demonstrated by the live cell barcoding of clinical samples with B cell abnormalities. In total, the samples from six various donors were successfully barcoded using only two detection channels. This barcoding of clinical samples enables sample preparation and measurement in a single tube.

• Klíčová slova
• antibody-polymer-dye conjugates, cellular barcoding, double fluorescence, flow cytometry, nanoprobes,
• MeSH
• fluorescenční barviva * chemie   MeSH
• imunofenotypizace MeSH
• polymery MeSH
• protilátky * MeSH
• průtoková cytometrie metody   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• fluorescenční barviva * MeSH
• polymery MeSH
• protilátky * MeSH

Multimodal imaging-therapeutic nanoprobe TiO(2)@RhdGd was prepared and successfully used for in vitro and in vivo cell tracking as well as for killing of cancer cells in vitro. TiO(2) nanoparticles were used as a core for phosphonic acid modified functionalities, responsible for contrast in MRI and optical imaging. The probe shows high (1)H relaxivity and relaxivity density values. Presence of fluorescent dye allows for visualization by means of fluorescence microscopy. The applicability of the probe was studied, using mesenchymal stem cells, cancer HeLa cells, and T-lymphocytes. The probe did not exhibit toxicity in any of these systems. Labeled cells were successfully visualized in vitro by means of fluorescence microscopy and MRI. Furthermore, it was shown that the probe TiO(2)@RhdGd can be changed into a cancer cell killer upon UV light irradiation. The above stated results represent a valuable proof of a principle showing applicability of the probe design for diagnosis and therapy.

• MeSH
• afinitní značky chemická syntéza   chemie   farmakologie   MeSH
• antitumorózní látky chemická syntéza   chemie   farmakologie   MeSH
• fluorescenční barviva chemická syntéza   chemie   farmakologie   MeSH
• fluorescenční mikroskopie MeSH
• gadolinium MeSH
• HeLa buňky MeSH
• komplexní sloučeniny chemická syntéza   chemie   farmakologie   MeSH
• léky antitumorózní - screeningové testy MeSH
• lidé MeSH
• magnetická rezonanční tomografie MeSH
• mezenchymální kmenové buňky metabolismus   MeSH
• myši MeSH
• nanočástice * MeSH
• organofosfonáty chemická syntéza   chemie   farmakologie   MeSH
• T-lymfocyty metabolismus   MeSH
• titan chemie   farmakologie   MeSH
• ultrafialové záření MeSH
• viabilita buněk účinky léků   MeSH
• vztahy mezi strukturou a aktivitou MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• afinitní značky MeSH
• antitumorózní látky MeSH
• fluorescenční barviva MeSH
• gadolinium MeSH
• komplexní sloučeniny MeSH
• organofosfonáty MeSH
• titan MeSH
• titanium dioxide MeSH Prohlížeč

Bovine serum albumin-embedded Au nanoclusters (BSA-AuNCs) are thoroughly probed by continuous wave electron paramagnetic resonance (CW-EPR), light-induced EPR (LEPR), and sequences of microscopic investigations performed via high-resolution transmission electron microscopy (HR-TEM), scanning transmission electron microscopy (STEM), and energy dispersive X-ray analysis (EDS). To the best of our knowledge, this is the first report analyzing the BSA-AuNCs by CW-EPR/LEPR technique. Besides the presence of Au(0) and Au(I) oxidation states in BSA-AuNCs, the authors observe a significant amount of Au(II), which may result from a disproportionation event occurring within NCs: 2Au(I) → Au(II) + Au(0). Based on the LEPR experiments, and by comparing the behavior of BSA versus BSA-AuNCs under UV light irradiation (at 325 nm) during light off-on-off cycles, any energy and/or charge transfer event occurring between BSA and AuNCs during photoexcitation can be excluded. According to CW-EPR results, the Au nano assemblies within BSA-AuNCs are estimated to contain 6-8 Au units per fluorescent cluster. Direct observation of BSA-AuNCs by STEM and HR-TEM techniques confirms the presence of such diameters of gold nanoclusters in BSA-AuNCs. Moreover, in situ formation and migration of Au nanostructures are observed and evidenced after application of either a focused electron beam from HR-TEM, or an X-ray from EDS experiments.

• Klíčová slova
• fluorescent nanoprobe, gold nanostructures, noble metal nanocrystal, protein nanocomposite,
• Publikační typ
• časopisecké články MeSH

Protein-protein interaction was investigated using a protein nanoprobe capable of photo-initiated cross-linking in combination with high-resolution and tandem mass spectrometry. This emerging experimental approach introduces photo-analogs of amino acids within a protein sequence during its recombinant expression, preserves native protein structure and is suitable for mapping the contact between two proteins. The contact surface regions involved in the well-characterized interaction between two molecules of human 14-3-3ζ regulatory protein were used as a model. The employed photo-initiated cross-linking techniques extend the number of residues shown to be within interaction distance in the contact surface of the 14-3-3ζ dimer (Gln8-Met78). The results of this study are in agreement with our previously published data from molecular dynamic calculations based on high-resolution chemical cross-linking data and Hydrogen/Deuterium exchange mass spectrometry. The observed contact is also in accord with the 14-3-3ζ X-ray crystal structure (PDB 3dhr). The results of the present work are relevant to the structural biology of transient interaction in the 14-3-3ζ protein, and demonstrate the ability of the chosen methodology (the combination of photo-initiated cross-linking protein nanoprobes and mass spectrometry analysis) to map the protein-protein interface or regions with a flexible structure.

• MeSH
• fotochemické procesy MeSH
• lidé MeSH
• mapování interakce mezi proteiny metody   MeSH
• molekulární modely MeSH
• multimerizace proteinu MeSH
• proteiny 14-3-3 chemie   metabolismus   MeSH
• sekvence aminokyselin MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice metody   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• proteiny 14-3-3 MeSH

"All-in-one" multifunctional nanomaterials, which can be visualized simultaneously by several imaging techniques, are required for the efficient diagnosis and treatment of many serious diseases. This report addresses the design and synthesis of upconversion magnetic NaGdF4:Yb3+/Er3+(Tm3+) nanoparticles by an oleic acid-stabilized high-temperature coprecipitation of lanthanide precursors in octadec-1-ene. The nanoparticles, which emit visible or UV light under near-infrared (NIR) irradiation, were modified by in-house synthesized PEG-neridronate to facilitate their dispersibility and colloidal stability in water and bioanalytically relevant phosphate buffered saline (PBS). The cytotoxicity of the nanoparticles was determined using HeLa cells and human fibroblasts (HF). Subsequently, the particles were modified by Bolton-Hunter-neridronate and radiolabeled by 125I to monitor their biodistribution in mice using single-photon emission computed tomography (SPECT). The upconversion and the paramagnetic properties of the NaGdF4:Yb3+/Er3+(Tm3+)@PEG nanoparticles were evaluated by photoluminescence, magnetic resonance (MR) relaxometry, and magnetic resonance imaging (MRI) with 1 T and 4.7 T preclinical scanners. MRI data were obtained on phantoms with different particle concentrations and during pilot long-time in vivo observations of a mouse model. The biological and physicochemical properties of the NaGdF4:Yb3+/Er3+(Tm3+)@PEG nanoparticles make them promising as a trimodal optical/MRI/SPECT bioimaging and theranostic nanoprobe for experimental medicine.

• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH