Nanoparticle-Doped Hybrid Polyelectrolyte Microcapsules with Controlled Photoluminescence for Potential Bioimaging Applications

Fluorescent imaging is widely used in the diagnosis and tracking of the distribution, interaction, and transformation processes at molecular, cellular, and tissue levels. To be detectable, delivery systems should exhibit a strong and bright fluorescence. Quantum dots (QDs) are highly photostable fluorescent semiconductor nanocrystals with wide absorption spectra and narrow, size-tunable emission spectra, which make them suitable fluorescent nanolabels to be embedded into microparticles used as bioimaging and theranostic agents. The layer-by-layer deposition approach allows the entrapping of QDs, resulting in bright fluorescent microcapsules with tunable surface charge, size, rigidity, and functional properties. Here, we report on the engineering and validation of the structural and photoluminescent characteristics of nanoparticle-doped hybrid microcapsules assembled by the deposition of alternating oppositely charged polyelectrolytes, water-soluble PEGylated core/shell QDs with a cadmium selenide core and a zinc sulfide shell (CdSe/ZnS), and carboxylated magnetic nanoparticles (MNPs) onto calcium carbonate microtemplates. The results demonstrate the efficiency of the layer-by-layer approach to designing QD-, MNP-doped microcapsules with controlled photoluminescence properties, and pave the way for the further development of next-generation bioimaging agents based on hybrid materials for continuous fluorescence imaging.

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Schottky Solar Cells with CuInS2 Nanocrystals as Absorber Material

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2014-0595 ◽

2015 ◽

Vol 229 (1-2) ◽

Cited By ~ 7

Author(s):

Holger Borchert ◽

Dorothea Scheunemann ◽

Katja Frevert ◽

Florian Witt ◽

Andreas Klein ◽

...

Keyword(s):

Solar Cells ◽

Semiconductor Nanocrystals ◽

Absorber Layer ◽

Limiting Factor ◽

Device Performance ◽

Layer By Layer ◽

Copper Indium Disulfide ◽

Layer Deposition ◽

Absorber Material ◽

Cadmium And Lead

AbstractColloidal semiconductor nanocrystals with tunable optical properties are promising materials for light harvesting in solar cells. So far, in particular cadmium and lead chalcogenide nanocrystals were intensively studied in this respect, and the device performance has made rapid progress in recent years. In contrast, less research efforts were undertaken to develop solar cells based on Cd- and Pb-free nanoparticles as absorber material. In the present work, we report on Schottky solar cells with the absorber layer made of colloidal copper indium disulfide nanocrystals. Absorber films with up to ∼ 500 nm thickness were realized by a solution-based layer-by-layer deposition technique. The device performance was systematically studied dependent on the absorber layer thickness. Decreasing photocurrent densities with increasing thickness revealed charge transport to be a limiting factor for the device performance.

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Layer-by-layer deposition of oppositely charged polyelectrolytes on the surface of condensed DNA particles

Nucleic Acids Research ◽

10.1093/nar/27.15.3090 ◽

1999 ◽

Vol 27 (15) ◽

pp. 3090-3095 ◽

Cited By ~ 70

Author(s):

V. S. Trubetskoy ◽

A. Loomis ◽

J. E. Hagstrom ◽

V. G. Budker ◽

J. A. Wolff

Keyword(s):

Layer By Layer ◽

Layer Deposition ◽

Oppositely Charged ◽

Condensed Dna

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FRET Studies Between CdTe Capped by Small-Molecule Ligands and Fluorescent Protein

International Journal of Nanoscience ◽

10.1142/s0219581x14600138 ◽

2014 ◽

Vol 13 (05n06) ◽

pp. 1460013

Author(s):

Yue Zhang ◽

Dejian Zhou ◽

Junhui He

Keyword(s):

Fluorescent Protein ◽

Organic Dyes ◽

Fluorescent Proteins ◽

Semiconductor Nanocrystals ◽

Resonance Energy ◽

Emission Spectra ◽

Binding Constants ◽

Dipole Interaction ◽

Water Soluble ◽

Donor Acceptor

Water-soluble luminescent semiconductor nanocrystals also known as quantum dots (QDs) that have prominent photostability, wide absorption cross sections and tunable narrow emission, have been shown as promising probes in immunoassays. QDs are often used as donors in fluorescence resonance energy transfer (FRET) based sensors using organic dyes or fluorescent proteins as acceptors. Here, the FRET between a QD donor and fluorescent protein acceptors has been studied. The fluorescent protein (FP)mCherry appended with a hexa-histidine-tag could effectively self-assemble onto CdTe to produce small donor-acceptor distances and hence highly efficient FRET (efficiency > 80%) at relatively low FP: CdTe copy numbers (ca.1). Using the Förster dipole–dipole interaction formula, the Förster radius (R0) and respective donor-acceptor distances for the CdTe -FP FRET systems have been calculated. The binding constants (Kd) of the QD-FP systems have also been evaluated by the emission spectra.

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Layer-by-Layer Deposition: A Promising Environmentally Benign Flame-Retardant Treatment for Cotton, Polyester, Polyamide and Blended Textiles

Materials ◽

10.3390/ma15020432 ◽

2022 ◽

Vol 15 (2) ◽

pp. 432

Author(s):

Eva Magovac ◽

Bojana Vončina ◽

Igor Jordanov ◽

Jaime C. Grunlan ◽

Sandra Bischof

Keyword(s):

Flame Retardant ◽

Inorganic Compounds ◽

Green Technology ◽

Layer By Layer ◽

Covalent Bonds ◽

Layer Deposition ◽

Low Concentrations ◽

Recent Developments ◽

Finishing Processes ◽

Oppositely Charged

A detailed review of recent developments of layer-by-layer (LbL) deposition as a promising approach to reduce flammability of the most widely used fibers (cotton, polyester, polyamide and their blends) is presented. LbL deposition is an emerging green technology, showing numerous advantages over current commercially available finishing processes due to the use of water as a solvent for a variety of active substances. For flame-retardant (FR) purposes, different ingredients are able to build oppositely charged layers at very low concentrations in water (e.g., small organic molecules and macromolecules from renewable sources, inorganic compounds, metallic or oxide colloids, etc.). Since the layers on a textile substrate are bonded with pH and ion-sensitive electrostatic forces, the greatest technological drawback of LbL deposition for FR finishing is its non-resistance to washing cycles. Several possibilities of laundering durability improvements by different pre-treatments, as well as post-treatments to form covalent bonds between the layers, are presented in this review.

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Layer-by-layer deposition of colloidal semiconductor nanocrystals for integration of infrared photon-detectors on 3D topography

2011 16th International Solid-State Sensors, Actuators and Microsystems Conference ◽

10.1109/transducers.2011.5969819 ◽

2011 ◽

Author(s):

J. Wei ◽

Y. Gao ◽

A.J. Houtepen ◽

G. Pandraud ◽

P.M. Sarro

Keyword(s):

Semiconductor Nanocrystals ◽

Layer By Layer ◽

Photon Detectors ◽

3D Topography ◽

Layer Deposition ◽

Colloidal Semiconductor Nanocrystals ◽

Infrared Photon ◽

Colloidal Semiconductor

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Hybrid photovoltaic cells with II–VI quantum dot sensitizers fabricated by layer-by-layer deposition of water-soluble components

Thin Solid Films ◽

10.1016/j.tsf.2009.06.039 ◽

2009 ◽

Vol 518 (1) ◽

pp. 295-298 ◽

Cited By ~ 32

Author(s):

Rolf Kniprath ◽

Jürgen P. Rabe ◽

James T. McLeskey ◽

Dayang Wang ◽

Stefan Kirstein

Keyword(s):

Quantum Dot ◽

Photovoltaic Cells ◽

Water Soluble ◽

Layer By Layer ◽

Layer Deposition ◽

Soluble Components

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Heterojunction of Hydrophobic Poly(1,4-phenylenevinylene) and Hydrophilic PEDOT:PSS on Hydrophilic CdS Nanoparticles

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2008.ic53 ◽

2008 ◽

Vol 8 (9) ◽

pp. 4730-4733 ◽

Cited By ~ 3

Author(s):

Wonjoo Lee ◽

Su Jin Baek ◽

Sun Ki Min ◽

Gangri Cai ◽

Joong Ki Lee ◽

...

Keyword(s):

Thermal Treatment ◽

Water Soluble ◽

Cds Nanoparticles ◽

Layer By Layer ◽

Deposition Method ◽

Water Contact ◽

Styrene Sulfonate ◽

Layer Deposition ◽

Poly Styrene Sulfonate ◽

Positively Charged

Heterojunction of hydrophobic poly(1,4-phenylenevinylene) (PPV) on hydrophilic CdS nanoparticles was successfully prepared by the multi-layering of poly(p-xylene tetrahydrothiophenium chloride) (pre-PPV: precursor of PPV polymer) and poly(3,4-ethylenedioxythiophene)/poly(styrene sulfonate) (PEDOT:PSS) in an aqueous solution followed by a thermal treatment. CdS nanoparticles thin films were prepared on tin-doped indium oxide (ITO) by a chemical-bath-deposition method. The CdS surface was hydrophilic with low water contact angle of 15°. Positively charged and water-soluble pre-PPV was used to form multilayers with PEDOT:PSS by a layer-by-layer deposition method. Pre-PPV is easily converted to conjugated PPV polymer by a thermal treatment. The CdS nanoparticles-(PPV/PEDOT:PSS) multilayer films constitute efficient acceptor-sensitizer dyad systems, which generate a photocurrent of 2,660 nA/cm2 under the air mass (AM) 1.5 conditions (I = 100 mW/cm2) for sample with 4.5 bilayers.

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Biofunctionalized Polyelectrolyte Microcapsules Encoded with Fluorescent Semiconductor Nanocrystals for Highly Specific Targeting and Imaging of Cancer Cells

Photonics ◽

10.3390/photonics6040117 ◽

2019 ◽

Vol 6 (4) ◽

pp. 117 ◽

Cited By ~ 1

Author(s):

Galina Nifontova ◽

Daria Kalenichenko ◽

Maria Baryshnikova ◽

Fernanda Ramos Gomes ◽

Frauke Alves ◽

...

Keyword(s):

Tumor Cells ◽

Size Structure ◽

Semiconductor Nanocrystals ◽

Transport Processes ◽

The Body ◽

Water Soluble ◽

Fluorescence Signal ◽

Layer By Layer ◽

Polyelectrolyte Microcapsules ◽

Fluorescent Semiconductor Nanocrystals

Fluorescent semiconductor nanocrystals or quantum dots (QDs) are characterized by unique optical properties, including a high photostability, wide absorption spectrum, and narrow, symmetric fluorescence spectrum. This makes them attractive fluorescent nanolabels for the optical encoding of microcarriers intended for targeted drug delivery, diagnosis, and imaging of transport processes on the body, cellular, and subcellular levels. Incorporation of QDs into carriers in the form of polyelectrolyte microcapsules through layer-by-layer adsorption of oppositely charged polyelectrolyte polymers yields microcapsules with a bright fluorescence signal and adaptable size, structure, and surface characteristics without using organic solvents. The easily modifiable surface of the microcapsules allows for its subsequent functionalization with capture molecules, such as antibodies, which ensures specific and selective interaction with cells, including tumor cells, with the use of the bioconjugation technique developed here. We obtained stable water-soluble nanolabels based on QDs whose surface was modified with polyethylene glycol (PEG) derivatives and determined their colloidal and optical characteristics. The obtained nanocrystals were used to encode polyelectrolyte microcapsules optically. The microcapsule surface was modified with humanized monoclonal antibodies (Abs) recognizing a cancer marker, epidermal growth factor receptor (EGFR). The possibility of effective, specific, and selective delivery of the microcapsules to tumor cells expressing EGFR has been demonstrated. The results show that the QD-encoded polyelectrolyte microcapsules functionalized with monoclonal Abs against EGFR can be used for targeted imaging and diagnosis.

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