Hierarchical self-assembly of metallo-supramolecular nanospheres

Cu(II)-Metallacryptands Self-Assembled to Vesicular Aggregates Capable of Encapsulating and Transporting an Anticancer Drug Inside Cancer Cells

Crystallographically characterized M₂ L₄ type cationic Cu(II)-metallacryptands [MC(X)] derived from a series of bis-pyridyl-bis-urea ligands (L_X ; X = O, S, C) are self-assembled to single-layered vesicular aggregates in DMSO, DMSO/water, and DMSO/DMEM (biological media). One such vesicle is MC(O)-vesicle that is demonstrated to be able to load and release (pH responsive) an anticancer drug, namely doxorubicin hydrochloride (DOX). DOX-loaded MC(O)-vesicle is also successfully transported within MDA-MB-231 cells-a highly aggressive human breast cancer cell line. Such self-assembling behavior to form vesicular aggregates by metallacryptands (MCs) is hitherto unknown.

Design and Synthesis of ZnII -Coordination Polymers Anchored with NSAIDs: Metallovesicle Formation and Multi-drug Delivery

A series of coordination polymers synthesized from a bis-pyridyl linker, namely 4,4'-azopyridine (L), selected non-steroidal-anti-inflammatory drugs (NSAIDs), namely diclofenac (Dic), ibuprofen (Ibu), flurbiprofen (Flu), mefenamic acid (Mefe), and naproxen (Nap), and Zn(NO₃ )₂ were characterized by single crystal X-ray diffraction. One of the coordination polymers, namely CP3 derived from Flu, was able to form metallovesicles in DMSO, DMSO/H₂ O and DMSO/DMEM (biological media) as revealed by TEM, AFM and DLS. Metallovesicle formation by CP3 was further supported by loading a fluorescent dye, namely calcein, as well as an anti-cancer drug, doxorubicin hydrochloride (DOX), as revealed by UV-vis and emission spectra, and fluorescence microscopy. DOX-loaded metallovesicles of CP3 (DOX@CP3-vesicle) could be delivered in vitro to a highly aggressive human breast cancer cell line, namely MDA-MB-231, as revealed by MTT and cell migration assays, and also cell imaging performed under laser scanning confocal microscope (LSCM). Thus, a proof of concept for developing a multi-drug delivery system derived from a metallovesicle for delivering an anti-cancer drug to cancer cells is demonstrated for the first time.

Multifunctional single-layered vesicles derived from Cu(ii)-metal–organic-polyhedra

Multifunctional vesicles derived from Cu(ii) metal–organic polyhedra (MOP) displayed the ability to encapsulate and release anti-cancer drug doxorubicin for the first time.