Testing Oligothiophene Fluorophores under Physiological Conditions. Preparation and Optical Characterization of the Conjugates of Bovine Serum Albumin with Oligothiophene N-Hydroxysuccinimidyl Esters

Scalable synthesis and purification of functionalized graphene nanosheets for water remediation

Microwave (MW) accelerated synthesis combined with microfiltration (MF) on commercial hollow fiber modules enables fast and scalable preparation of highly pure modified graphene oxide nanosheets. The MW-MF procedure is demonstrated on polyethylenimine (PEI) modified GO, and the so-obtained GOPEI is used for simultaneous removal of arsenic and lead from water.

Self-assembling oligothiophene–bolaamphiphiles for loading and controlled release of doxorubicin into living cells

Symmetric mannose-functionalized oligothiophenes for efficient transport and release of the anti-tumour drug doxorubicin.

Fluorescent thiophene-based materials and their outlook for emissive applications

An overview of fluorescent thiophene-based materials and their applications, highlighting in particular the various methods employed to achieve highly emissive materials.

Live cell cytoplasm staining and selective labeling of intracellular proteins by non-toxic cell-permeant thiophene fluorophores

A structurally correlated series of cell-permeant thiophene fluorophores, characterized by intense green or red fluorescence inside live mouse embryonic fibroblasts, was developed. The fluorophores displayed rapid internalization, excellent retention inside the cells, and high optical stability in the cytosolic environment and did not alter cell viability and reproducibility. Depending on the molecular structure, they experienced distinct fate inside the cells: from bright and lasting staining of the cytoplasm to selective tagging of a small set of globular proteins.

Thiophene-based compounds as fluorescent tags to study mesenchymal stem cell uptake and release of taxanes

Human mesenchymal stem cells (hMSC) are multipotent cells that display the unique ability to home and engraft in tumor stroma. This remarkable tumor tropic property has generated a great deal of interest in many clinical settings. Recently, we showed that hMSC represent an excellent base for cell-mediated anticancer therapy since they are able to internalize paclitaxel (PTX) and to release it in an amount sufficient to inhibit tumor cell proliferation. In order to shed light on the dynamics of drug uptake and release, in the present paper we describe the synthesis of two novel thiophene-based fluorophore-paclitaxel conjugates, namely PTX-F32 and PTX-F35, as tools for in vitro drug tracking. We aimed to study the ability of these novel derivatives to be efficiently internalized by hMSC and, in a properly engineered coculture assay, to be released in the medium and taken up by tumor cells. In order to ensure better stability of the conjugates toward enzymatic hydrolysis, the selected oligothiophenes were connected to the taxol core at the C7 position through a carbamate linkage between PTX and the diamino linker. Antiproliferative experiments on both tumor cells and stromal cells clearly indicate that, in good correlation with the parent compound, cells are sensitive to nanomolar concentrations of the fluorescent conjugates. Moreover, in the coculture assay we were able to monitor, by fluorescence microscopy, PTX-F32 trafficking from hMSC toward glioblastoma U87 tumor cells. Our work paves the way for novel possibilities to perform extensive and high quality fluorescence-based analysis in order to better understand the cellular mechanisms involved in drug trafficking, such as microvescicle/exosome mediated release, in hMSC vehicle cells.

Microwave-assisted synthesis of thiophene fluorophores, labeling and multilabeling of monoclonal antibodies, and long lasting staining of fixed cells

We report the expedient microwave-assisted synthesis of thiophene based 4-sulfo-2,3,5,6,-tetrafluorophenyl esters whose molecular structure was engineered to achieve blue to red bright fluorescence. The reactivity toward monoclonal antibodies of the newly synthesized fluorophores was analyzed in comparison with that of the corresponding N-succinimidyl esters. Single-fluorophore and multiple-fluorophore labeled antibodies were easily prepared with both types of esters. Multiple-fluorophore labeling with blue and orange emitting fluorophores resulted in white fluorescent antibodies. Thiophene based fluorophores displayed unprecedented fluorescence stability in immunostaining experiments. First-principles TD-DFT theoretical calculations helped us to interpret the behavior of fluorescence emission in different environments.