Quantum Rod Bioconjugates as Targeted Probes for Confocal and Two-Photon Fluorescence Imaging of Cancer Cells

Abstract

Live cell imaging using CdSe/CdS/ZnS quantum rods (QRs) as targeted optical probes is reported. The QRs, synthesized in organic media using a binary surfactant mixture, were dispersed in aqueous media using mercaptoundecanoic acid (MUA) and lysine. Transferrin (Tf) was linked to the QRs to produce QR-Tf bioconjugates that were used for targeted in vitro delivery to a human cancer cell line. Confocal and two-photon imaging were used to confirm receptor-mediated uptake of QR-Tf conjugates into the HeLa cells, which overexpress the transferrin receptor (TfR). Uptake was not observed with QRs that lacked Tf functionalization or with cells that were presaturated with free Tf and then treated with Tf-functionalized QRs.

Quantification of Anisotropy-Related Uncertainties in Relative Photoluminescence Quantum Yield Measurements of Nanomaterials – Semiconductor Quantum Dots and Rods

“…[20][21][22][23] The increasing importance in measuring PL of anisotropic emitters like dye-biomolecule conjugates and luminescent nanomaterials with e.g., a shapeinduced anisotropy encouraged us to study polarization-induced changes of the detection efficiency of a commercial fluorometer and to quantify polarizationrelated uncertainties of PL measurements. For this purpose, we chose quantum dot-rods (QDRs), a novel class of semiconductor nanocrystals increasingly used as reporters for bioanalytical applications and medical diagnostics [28][29][30] and active materials for plasma displays, which consist of a spherical core and an elongated shell. QDRs possess unique photophysical properties, such as size-tunable absorption and emission spectra (dependent on the core diameter), huge absorption cross-sections, and narrow, symmetric emission bands like spherical quantum dots (QDs).…”

Anti-HIV-1 nanotherapeutics: promises and challenges for the future

“…71 The high photostability of QDs emitting in the near-infrared spectral region facilitates the monitoring of this transport process in real-time via high-resolution optical imaging. 7,[72][73][74][75] Thus a QD/QR-based nanoplatform facilitates not only the delivery of an antiretroviral drug across the BBB via interaction with endogenous transferrin receptors on the BBB but also allows the real-time monitoring of this transendothelial migration process via optical imaging. We have demonstrated that antiretroviral drug-loaded nanoparticles can deliver effective therapeutics across the BBB and that our nanoformulation has great potential in the treatment of neuro-AIDS and other neurological disorders.…”

“…The use of nanotechnology for numerous biomedical applications has become an area of intense research over the last decade. [1][2][3][4][5][6][7][8][9][10] The potential advantages of using nanomedicine over conventional HIV therapies include the capacity to incorporate, encapsulate, or conjugate a variety of drugs to target specific cell populations and to offer tunable and site-specific drug release. [11][12][13][14][15][16][17][18][19][20] Table 1 outlines the different types of current nanotherapeutics in HIV and lists their advantages and limitations.…”

Aqueous phase synthesis of CdTe quantum dots for biophotonics

“…There are a number of strategies to deliver QDs to the cells, namely, transfection [65], electroporation, microinjection, uptake into cells via both targeting [66], and passive pathways are common routes for cell labeling and imaging [67]. In many cases, a targeted approach (e.g.…”