12 research outputs found
Visualization of melanoma tumor with lectin-conjugated rare-earth doped fluoride nanocrystals
Aim To develop specific fluorescent markers for melanoma
tumor visualization, which would provide high selectivity
and reversible binding pattern, by the use of carbohydrate-
recognizing proteins, lectins, combined with the
physical ability for imaging deep in the living tissues by utilizing
red and near infrared fluorescent properties of specific
rare-earth doped nanocrystals (NC).
Methods B10F16 melanoma cells were inoculated to
C57BL/6 mice for inducing experimental melanoma tumor.
Tumors were removed and analyzed by lectin-histochemistry
using LABA, PFA, PNA, HPA, SNA, GNA, and
NPL lectins and stained with hematoxylin and eosin. NPL
lectin was conjugated to fluorescent NaGdF4:Eu3+-COOH
nanoparticles (5 nm) via zero length cross-linking reaction,
and the conjugates were purified from unbound substances
and then used for further visualization of histological
samples. Fluorescent microscopy was used to visualize
NPL-NaGdF4:Eu3+ with the fluorescent emission at 600-720
nm range.
Results NPL lectin selectively recognized regions of undifferentiated
melanoblasts surrounding neoangiogenic foci
inside melanoma tumor, PNA lectin recognized differentiated
melanoblasts, and LCA and WGA were bound to tumor
stroma regions. NPL-NaGdF4:Eu3+ conjugated NC were
efficiently detecting newly formed regions of melanoma
tumor, confirmed by fluorescent microscopy in visible and
near infrared mode. These conjugates possessed high photostability
and were compatible with convenient xylenebased
mounting systems and preserved intensive fluorescent
signal at samples storage for at least 6 months.
Conclusion NPL lectin-NaGdF4:Eu3+ conjugated NC permitted
distinct identification of contours of the melanoma
tissue on histological sections using red excitation at 590-
610 nm and near infrared emission of 700-720 nm. These
data are of potential practical significance for development
of glycans-conjugated nanoparticles to be used for in vivo
visualization of melanoma tumor
CdS Dots, Rods and PlateletsâHow to Obtain Predefined Shapes in a One-Pot Synthesis of Nanoparticles
In recent years, numerous protocols for nanoplatelet synthesis have been developed. Here, we present a facile, one-pot method for controlling cadmium sulfide (CdS) nanoparticlesâ shape that allows for obtaining zero-dimensional, one-dimensional, or two-dimensional structures. The proposed synthesis protocol is a simple heating-up approach and does not involve any inconvenient steps such as injection and/or pouring the precursors at elevated temperatures. Because of this, the synthesis protocol is highly repeatable. A gradual increase in the zinc acetate concentration causes the particlesâ shape to undergo a transition from isotropic quantum dots through rods to highly anisotropic nanoplatelets. We identified conditions at which synthesized platelets were purely five monolayers thick. All samples acquired during different stages of the reaction were characterized via optical spectroscopy, which allowed for the identification of the presence of high-temperature, magic-size clusters prior to the plateletsâ formation
CdS Dots, Rods and PlateletsâHow to Obtain Predefined Shapes in a One-Pot Synthesis of Nanoparticles
In recent years, numerous protocols for nanoplatelet synthesis have been developed. Here, we present a facile, one-pot method for controlling cadmium sulfide (CdS) nanoparticlesâ shape that allows for obtaining zero-dimensional, one-dimensional, or two-dimensional structures. The proposed synthesis protocol is a simple heating-up approach and does not involve any inconvenient steps such as injection and/or pouring the precursors at elevated temperatures. Because of this, the synthesis protocol is highly repeatable. A gradual increase in the zinc acetate concentration causes the particlesâ shape to undergo a transition from isotropic quantum dots through rods to highly anisotropic nanoplatelets. We identified conditions at which synthesized platelets were purely five monolayers thick. All samples acquired during different stages of the reaction were characterized via optical spectroscopy, which allowed for the identification of the presence of high-temperature, magic-size clusters prior to the plateletsâ formation
Facile synthesis of phosphine free ultra-small PbSe nanocrystals and their light harvesting studies in ETA solar cells
Ultra-small PbSe nanocrystals (NCs) were synthesized via a âone-potâ approach in olive oil as the reaction medium and capping agent.</p
CdS Nanoplates Modification as a Platform for Synthesis of Blue-Emitting Nanoparticles
In this paper, the study of surface modification of two-dimensional (2D), non-luminescent CdS nanoplates (NPLs) by thiol-containing ligands is presented. We show that a process of twophase transfers with appropriate ligand exchange transforms non-luminescent NPLs into spherical CdS nanoparticles (NPs) exhibiting a blue photoluminescence with exceptionally high quantum yield ~90%. In the process, transfer from inorganic solvent to water is performed, with appropriately selected ligand molecules and pH values (forward phase transfer), which produces NPs with modified size and shape. Then, in reverse phase transfer, NPs are transferred back to toluene due to surface modification by combined Cd (OL)2 and Cd (Ac)2. As a result, spherical NPs are formed (average diameter between 4 and 6 nm) with PL QY as high as 90%. This is unique for core only CdS NPs without inorganic shell
Special Role for Zinc Stearate and Octadecene in the Synthesis of Luminescent ZnSe Nanocrystals
Special Role for Zinc Stearate and Octadecene in the
Synthesis of Luminescent ZnSe Nanocrystal
Controlled synthesis of tuned bandgap nanodimensional alloys of PbS xSe1-x
Truly alloyed PbSxSe1âx (x = 0â1) nanocrystals (âŒ5 nm in size) have been prepared, and their resulting optical properties are red-shifted systematically as the sulfur content of the materials increases. Their optical properties are discussed using a modified Vegardâs approach and the bowing parameter for these nanoalloys is reported for the first time. The alloyed structure of the nanocrystals is supported by the energy-filtered transmission electron microscope images of the samples, which show a homogeneous distribution of sulfur and selenium within the nanocrystals. X-ray photoelectron spectroscopy studies on ligand-exchanged nanocrystals confirmed the expected stoichiometry and various oxidized species