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Targeted tumor imaging in vivo has been one of the main challenges in the early stage of cancer diagnosis and therapy. However, few contrast probes are available to specifically respond to tumor environments. The aim was to investigate porphyrin‐1,8‐naphthalimide derivative (APTSPP‐2NI) as a potential tumor‐targeting fluorescent probe in vitro and in vivo. A tumor‐targeting APTSPP‐2NI was synthesized by the incorporation of water‐soluble 5‐(4'‐aminophenyl)‐10,15,20‐tris(4'‐sulfonato‐phenyl) porphyrin (APTSPP) as a tumor‐targeting group into N‐butyl‐4‐ethyldiamino‐1,8‐naphthalene imide (NI) fluorescence molecule herein. The derivative was further characterized and its properties in vitro and in vivo including the cell cytotoxicity, cell uptake of tumor cells and fluorescent imaging were also evaluated. Experiment results indicated that APTSPP‐2NI possessed the low cell cytotoxicity and good tumor‐targeting property to the B16F10 melanoma cells. Moreover, APTSPP‐2NI can be taken up highly by B16F10 melanoma tumors and then achieve the good green and red fluorescent imaging in B16F10 melanoma tumors. Therefore APTSPP‐2NI can be considered as a potential tumor‐targeting dual‐mode enhanced probe in fluorescent imaging in vitro and in vivo. [ABSTRACT FROM AUTHOR]

In recent decades, diverse drug delivery systems (DDS) constructed by self-assembly of dendritic peptides have shown advantages and improvable potential for cancer treatment. Here, an arginine-enriched dendritic amphiphilic chimeric peptide CRRK(RRCG(Fmoc))2 containing multiple thiol groups is programmed to form drug-loaded nano-micelles by self-assembly. With a rational design, the branched hydrophobic groups (Fmoc) of the peptides provide a strong hydrophobic force to prevent the drug from premature release, and the reduction-sensitive disulfide linkages formed between contiguous peptides can control drug release under reducing stimulation. As expected, specific to multidrug resistance (MDR) tumor cells, the arginine-enriched peptide/drug (PD) nano-micelles show accurate nuclear localization ability to prevent the drug being pumped by P-glycoprotein (P-gp) in vitro, as well as exhibiting satisfactory efficacy for MDR tumor treatment in vivo. This design successfully realizes stimuli-responsive drug release aimed at MDR tumor cells via an ingenious sequence arrangement. [ABSTRACT FROM AUTHOR]

Isoindoline nitroxide-containing porphyrins were synthesized by the reaction of 5-phenyldipyrromethane and 5-(4′-nitrophenyl)-dipyrromethane with 5-formyl-1,1,3,3-tetramethylisoindolin-2-yloxyl using the Lindsey method. These spin-labeled porphyrins were further characterized by MS, UV, FTIR, 1H-NMR, cyclic voltammetry, electron paramagnetic resonance (EPR), and fluorescence spectroscopy. The electrochemical assay demonstrated that these isoindoline nitroxides-containing porphyrins had similar electrochemical and redox properties as 5-carboxy-1,1,3,3-tetramethylisoindolin-2-yloxyl. Electron paramagnetic resonance test exhibited these porphyrins possessed the hyperfine splittings and characteristic spectra of isoindoline nitroxides, with typical nitroxide g-values and nitrogen isotropic hyperfine coupling constants. Fluorescence spectroscopy revealed that these porphyrins indicated fluorescence suppression characteristic of nitroxide-fluorophore systems. Moreover, their reduced isoindoline nitroxide-containing porphyrins eliminated the fluorescence suppression and displayed strong fluorescence. Thus, these isoindoline nitroxide-containing porphyrins may be considered as the potential fluorescent and EPR probes. [ABSTRACT FROM AUTHOR]

A novel supramolecular framework, catena-poly[[[aqua(2-phenylquinoline-4-carboxylato-κ O)silver(I)]-μ-4,4′-bipyridine-κ2 N: N′] dihydrate], {[Ag(C16H10NO2)(C10H8N2)(H2O)]·2H2O} n, has been synthesized and structurally characterized. The AgI centres are four-coordinated and bridged by 4,4′-bipyridine (4,4′-bipy) ligands to form a one-dimensional Ag-bipy chain. The Ag-bipy chains are further linked together by intermolecular O-H...O and O-H...N hydrogen-bonding interactions between adjacent chains, resulting in a three-dimensional framework. [ABSTRACT FROM AUTHOR]