The design of self oxidation-resistant catalytic materials based on organic molecules, although advantageous due to the ability to control their structures, is limited by the presence of labile C–H bonds. This mini review summarizes recent work aimed at first-row transition metal complexes of a new class of coordinating ligands, fluoroalkyl-substituted fluorophthalocyanines, R[Formula: see text]Pcs, ligands in which all, or the majority of their C–H bonds are replaced by a combination of fluoro- and perfluoroalkyl groups yielding porphyrin-bioinspired catalyst models. In the case of homogeneous systems, cobalt(II) complexes catalyze the aerobic oxidation of thiols to disulfides, a reaction of both biological significance and industrial importance. Zinc(II) complexes photo-generate excited state singlet oxygen, [Formula: see text]O[Formula: see text], resulting in both the incorporation of O[Formula: see text] in C–H bonds or, depending on the reaction parameters, oxidation of dyes, model pollutants. Catalyst heterogenization using oxidic and other supports yields stable, active hybrid materials. Functionalized R[Formula: see text]Pcs with acidic (–COOH) or basic (–NH[Formula: see text]R[Formula: see text], [Formula: see text] 2) groups exhibit scaffolds that afford both conjugation with biological vectors for theranostic applications as well as solid-supported materials with superior stability. Electrodes modified with hybrid R[Formula: see text]Pc-containing supports have also been used in photo-oxidations, replacing enzymes and H[Formula: see text]O[Formula: see text] associated reagents with a combination of light and air. An analytical device employed for the nano-level detection of environmentally deleterious antibiotics has been constructed.

The first representative of functionalized fluoroalkyl phthalocyanines, F48H7(COOH)PcZn, is reported. The complex generates (1)O2 affording long-lasting photooxidation of an external substrate without self-decomposition. The carboxylic group couples with an antisense oligonucleotide targeting GRP78 oncogenes, resulting in the F48H7PcZn-cancer targeting oligonucleotide (CTO). The bioconjugated fluorophthalocyanine effectively hybridizes complementary GRP78 DNA and mRNA sequences. Piperidine cleavage assays reveal desired photochemical oligonucleotide oxidative degradation for both F48H7PcZn-CTO:DNA and F48H7PcZn-CTO:mRNA hybrids. This new materials strategy could be extended to other functional fluorinated phthalocyanines-antisense oligonucleotide combinations for long-lasting oncogene-targeting photodynamic therapy.

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Singlet oxygen plays a crucial role in photo-dermatology and photodynamic therapy (PDT) of cancer. Its direct observation by measuring the phosphorescence at 1270 nm, however, is still challenging due to the very low emission probability. It is especially challenging for the time-resolved detection of singlet oxygen kinetics in vivo which is of special interest for biomedical applications. Photosensitized generation of singlet oxygen, in pig ear skin as model for human skin, is investigated here. Two photosensitizers (PS) were topically applied to the pig ear skin and examined in a comparative study, which include the amphiphilic pheophorbide-a and the highly hydrophobic perfluoroalkylated zinc phthalocyanine (F64PcZn). Fluorescence microscopy indicates the exclusive accumulation of pheophorbide-a in the stratum corneum, while F64PcZn can also accumulate in deeper layers of the epidermis of the pig ear skin. The kinetics obtained with phosphorescence measurements show the singlet oxygen interaction with the PS microenvironment. Different generation sites of singlet oxygen correlate with the luminescence kinetics. The results show that singlet oxygen luminescence detection can be used as a diagnostic tool, not only for research, but also during treatment. The detection methodology is suitable for the monitoring of chemical quenchers’ oxidation as well as saturation at singlet oxygen concentration levels relevant to PDT treatment protocols.