Water soluble porphyrin-fluorescein triads: Design, DFT calculation and pH-change-triggered fluorescence response

A convenient protocol for the preparation of 5-phenyl-10,15,20-tris(4-sulfonatophenyl)porphyrin, a water-soluble porphyrin with unique aggregation properties, is described. The procedure relies on the one-pot reductive deamination of 5-(4-aminophenyl)-10,15,20-tris(4-sulfonatophenyl)porphyrin, that can be in turn easily obtained from 5,10,15,20-tetraphenylporphyrin by a known three-step sequence involving mononitration, nitro to amine reduction and sulfonation of the phenyl groups. This method provides the title porphyrin in gram scale, and compares very favorably with the up to now only described procedure based on the partial sulfonation of TPP, that involves a long and tedious chromatographic enrichment of the final compound. This has allowed us to study for the first time both the use of its zwitterionic aggregate as a supramolecular catalyst of the aqueous Diels–Alder reaction, and the morphology of the aggregates obtained under optimized experimental conditions by atomic force microscopy and also by transmission electron cryomicroscopy.

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Colorimetric and fluorescent on-off detection of Cu2+, Sn2+ and Zn2+ by a water-soluble porphyrin: Electronic absorption and emission study

Results in Chemistry ◽

10.1016/j.rechem.2020.100058 ◽

2020 ◽

Vol 2 ◽

pp. 100058 ◽

Cited By ~ 1

Author(s):

Belete B. Beyene ◽

Amogne W. Yibeltal ◽

Misganaw T. Ayana

Keyword(s):

Electronic Absorption ◽

Water Soluble ◽

Absorption And Emission ◽

Emission Study ◽

Water Soluble Porphyrin

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A marine isolate of Pseudomonas nigrifaciens. I. Classification and nutrition

Canadian Journal of Microbiology ◽

10.1139/m68-223 ◽

1968 ◽

Vol 14 (12) ◽

pp. 1333-1340 ◽

Cited By ~ 1

Author(s):

Cynthia F. Norton ◽

Galen E. Jones

Keyword(s):

Rhode Island ◽

Culture Fluid ◽

Chloride Ion ◽

Water Soluble ◽

Redox Activity ◽

Blue Pigment ◽

Ph Indicator ◽

Ph Change ◽

Deep Blue ◽

Solid Media

A bacterium producing a deep blue pigment was isolated from Narragansett Bay, Rhode Island, and identified as Pseudomonas nigrifaciens. It requires at least 6.4 p.p.t. salinity for growth, 9.6 p.p.t. for pigmentation, and grows from 4 to 30 C, optimally at 15–18 C. An organic nitrogen source is necessary for growth but no specific amino acids or growth factors are required. Two major seawater ions are essential, potassium (10−3 M minimum, 8 × 10−3 M optimum) and magnesium (growth occurring in 1 week on 10−5 M, 10−2 M optimum at 20 h). Growth occurs without addition of sodium or chloride ion. Optimum pigmentation occurs on solid media, but pigmentation does occur in shaken vitamin-free casamino acids medium of 35 p.p.t. salinity. Water-soluble blue pigment appears during log phase and breaks down to a brownish coloration during stationary phase, coinciding with a pH change from 7.4 to 8.3. The blue pigment in sterile filtered culture fluid exhibits redox and pH indicator properties. Redox activity is observed in culture fluid, where standing causes reduction and shaking reoxidation.

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