Water soluble fluorescent-magnetic perylenediimide-containing maghemite-nanoparticles for bimodal MRI/OI imaging

New Highly Fluorescent Water Soluble Imidazolium-Perylenediimides: Synthesis and Cellular Response

The synthesis and characterization of two new water soluble 2,6-bis(imidazolylmethyl)-4-methylphenoxy-containing perylenediimides, PDI-1 and PDI-2, are described. These compounds demonstrate a high fluorescence quantum yield in water and were investigated as potential photosensitizers for generating reactive oxygen species with applications in anticancer activities. The HeLa cell line (VPH18) was used to evaluate their efficacy. Fluorescence microscopy was employed to confirm the successful internalization of PDI-1 and PDI-2, while confocal microscopy revealed the specific locations of both PDIs within the lysosomes and mitochondria. In vitro studies were conducted to evaluate the anticancer activity of PDI-1 and PDI-2. Remarkably, these photosensitizers demonstrated a significant ability to selectively eliminate cancer cells when exposed to a specific light wavelength. The water solubility, high fluorescence quantum yield, and selective cytotoxicity of these PDIs toward cancer cells highlight their potential as effective agents for targeted photodynamic therapy. In conclusion, the findings presented here provide a strong foundation for the future exploration and optimization of PDI-1 and PDI-2 as effective photosensitizers in photodynamic therapy, potentially leading to improved treatment strategies for cancer patients.

Medical Imaging Technology and Imaging Agents

Medical imaging is a technology that studies the interaction between human body and irradiations of X-ray, ultrasound, magnetic field, etc. and represents anatomical structures of human organs/tissues with the implication of irradiation attenuation in the form of grayscales. With these medical images, detailed information on health status and disease diagnosis may be judged by clinical physicians to determine an appropriate therapy approach. This chapter will give a systematic introduction on the modalities, classifications, basic principles, and biomedical applications of traditional medical imaging along with the types, construction, and major features of the corresponding contrast agents or imaging probes.

Synthesis of Dipyridylaminoperylenediimide-Metal Complexes and Their Cytotoxicity Studies

A new family of perylenediimide (PDI) silver and copper complexes has been successfully synthesized by reacting ortho- and bay-substituted (dipyrid-2',2″-ylamino)perylenediimide ligands with metal phosphine fragments. The coordination of the metal center did not reveal a significant effect on the photophysical properties, which are mainly due to the PDI ligands, and in some cases quenching of the luminescence was observed. The antiproliferative effect of the free perylenediimide ligands and the metalloPDI complexes against the cervix cancer cell line HeLa was determined by MTT assay. The free perylenediimide ligands exhibited a moderate cytotoxic activity, but the coordination of silver or copper to the dypyridylamino fragment greatly enhanced the activity, suggesting a synergistic effect between the two fragments. In attempts to elucidate the cellular biodistribution of the PDIs and the complexes, a colocalization experiment using specific dyes for the lysosomes or mitochondria as internal standards revealed a major internalization inside the cell for the metal complexes, as well as a partial mitochondrial localization.

Diels–Alder reaction on perylenediimides: synthesis and theoretical study of core-expanded diimides

(Un)substituted perylenediimides react with (un)functionalized benzynes yielding core-expanded diimides.

Synthesis of bay-triaminosubstituted perylenediimides

A mild fluoride-mediated reaction for the synthesis of 1,6,7-triaminoperylenediimides.

Fluoride-mediated alkoxylation and alkylthio-functionalization of halogenated perylenediimides

The presence of fluoride ions in the reaction of chloro- or bromo-PDIs with alcohols and thiols leads to a spectacular increase in the yields of substituted compounds.

Perylenediimide-based glycoclusters as high affinity ligands of bacterial lectins: synthesis, binding studies and anti-adhesive properties

Rapid access to perylenediimide-based glycoclusters allowed their evaluation as high affinity ligands of bacterial lectins and their potential as anti-adhesive antibacterials.

Iron Oxide Nanoparticles Labeled with an Excited-State Intramolecular Proton Transfer Dye

Excited-state intramolecular proton transfer (ESIPT) is a particularly well known reaction that has been very little studied in magnetic environments. In this work, we report on the photophysical behavior of a known ESIPT dye of the benzothiazole class, when in solution with uncoated superparamagnetic iron oxide nanoparticles, and when grafted to silica-coated iron oxide nanoparticles. Uncoated iron oxide nanoparticles promoted the fluorescence quenching of the ESIPT dye, resulting from collisions during the lifetime of the excited state. The assembly of iron oxide nanoparticles with a shell of silica provided recovery of the ESIPT emission, due to the isolation promoted by the silica shell. The silica network gives protection against the fluorescence quenching of the dye, allowing the nanoparticles to act as a bimodal (optical and magnetic) imaging contrast agent with a large Stokes shift.

Direct alkylthio-functionalization of unsubstituted perylenediimides

A simple fluoride-mediated reaction allows the synthesis of 1,6-dialkylthioperylenediimides from unsubstituted perylenediimides under very mild conditions.