Differentiation of Folate‐Receptor‐Positive and ‐Negative Cells Using a Substrate‐Mimicking Fluorescent Probe

Abstract

Diagnosis and therapy exploiting overexpressed receptors on the cell surface is one important strategy in medicine. Determination of the over expression level of a particular receptor is prerequisite for it to be of clinical use. Differentiation between FR-positive (FR=folate receptor) and -negative cells via fluorescence microscopy using a substrate mimetic fluorophore is presented in this work. The strategy adopted here is not the classical FA-conjugated (FA=folic acid) fluorescent probe but a small and environment-sensitive pterin-based (pterin is part of folate, i.e., vitamin B9) fluorescent probe. Electronically diverse pterin-based fluorescent probes have been designed and synthesized to understand the effect of the binding environment on the receptor-substrate interactions. By utilizing steady-state UV/Vis and fluorescence along with time-resolved fluorescence spectroscopy, the effects on the electronic and acid-base properties of the substrate were investigated. Evidently, one synthesized probe showed FA-mimicking behavior with strong binding interaction with FR.

Multifunctional Magneto-Fluorescent Nanocarriers for Dual Mode Imaging and Targeted Drug Delivery

“…On the contrary to this, MFCSNPs-FA-CHI-5FU nanocarriers showed a noteworthy cell antiproliferative potential toward HeLa (51.54% cell viability at 200 μg/mL) and the activity was also found to be comparable with the cytotoxicity of free 5-FU toward the HeLa cell line. A375 cells are the folate receptor (FR) negative cell line and always used as a FR negative control, while the FR expression on the cell surface of MCF-7 is moderate as compared to the HeLa cells which have highly expressed FR markers. , Therefore, in the present study, synthesized MFCSNPs-FA-CHI-5FU nanocarriers that are folic acid conjugated show considerable cell cytotoxicity against HeLa cells. The obtained cytotoxicity of the MFCSNPs-FA-CHI-5FU nanocarriers is almost same in the A375 and MCF-7 because, although the MCF-7 cells show moderate FR expression, the IC 50 of 5-FU against the MCF-7 cell line is at higher range.…”

Folate‐Receptor‐Mediated Uptake of Carbon Dots as a pH‐Responsive Carrier for Chemotherapy

“…Also, very slight red fluorescence was observed from the nucleus of BHK‐21 cells as compared to HeLa cells, which suggests a greater release of Dox in the cytoplasm of HeLa cells along with the penetration of released Dox into the nucleus due to its DNA intercalation properties. The folate receptor is considered to be a biomarker for cancer as it is overexpressed in several tumors [17a,37] . It has been a popular choice for therapeutic and diagnostic tools to achieve targeted delivery to cancer cells.…”

Concanavalin A-conjugated gold nanoparticle/silica quantum dot (AuNPs/SiQDs-Con A)-based platform as a fluorescent nanoprobe for the bioimaging of glycan-positive cancer cells

“…The specificity of cit-AuNPs-MPA/Si-NH 2 QDs/Con A as a smart material was investigated using HEK 293 normal cells, in which glycan receptors are not expressed on the membrane of the cells. 40 HEK 293 cells were incubated with the cit-AuNPs-MPA/Si-NH 2 QDs/Con A NPs to check their possible attachment to the cell surface. The obtained results confirmed that the Con A-functionalized cit-AuNPs-MPA/Si-NH 2 QDs nanocomposite cannot be captured by the low-expressed normal cells; the obtained results confirmed the differentiating ability of cit-AuNPs-MPA/Si-NH 2 QDs/Con A NPs between HEK 293 glycan receptor-negative cells and glycan receptor-positive MCF-7 cells (Fig.…”

“…normal cells, in which glycan receptors are not expressed on the membrane of the cells 40. HEK 293 cells were incubated with the cit-AuNPs-MPA/Si-NH 2 QDs/Con A NPs to check their possible attachment to the cell surface.…”