We present results of a joint computational and experimental study for a series of annulated metalloporphyrins in order to establish structure−property relationships. Specifically, we have examined the effects of substitution by meso-tetraphenylation, tetrabenzo and tetranaphtho annulation, and effects of changing the central metal from zinc (Zn) to palladium (Pd). Utilizing absorption and emission spectroscopy and laser flash photolysis techniques, the photophysical properties of these porphyrins have been determined. Upon the addition of benzo or naphtho groups, we observed an overall red shift in the ground state absorption spectra of both the B-bands and the Q-bands with increased conjugation and an increase in the Q-band to B-band intensity ratios. Time-dependent density functional theory calculations were performed on both series of porphyrins to identify the effects of phenyl, benzo, and naphtho substituents on the spectra. The benzo and naphtho adducts provide a larger contribution (typically 40−9...

Observation and Interpretation of Annulated Porphyrins: Studies on the Photophysical Properties of meso-Tetraphenylmetalloporphyrins

The effects exerted by fused aromatic rings on the UV-vis spectra of porphyrins are surveyed. Modified porphyrin chromophores with fused benzene, 1,2-naphthalene, 9,10-phenanthrene or phenanthroline rings are surprisingly little affected even when a maximum number of ring fusions are incorporated. Linearly annealed naphtho- or anthraporphyrins show large red shifts to the Q bands but the Soret absorptions are weakened and undergo only minor bathochromic shifts. Fluoranthoporphyrins give multiple bands in the Soret region, but the Q band region is virtually unaffected by this tetracyclic ring system. On the other hand, metal chelates of fluoranthoporphyrins show surprisingly strong bands near 600 nm. Benzothiadiazole rings split and weaken the Soret band, but the Q bands region is unexceptional. However, metal coordination again produces relatively intense bands near 600 nm. The most significant results were obtained for porphyrins with fused acenaphthylene rings. Monoacenaphthoporphyrins (41) have three S...

Modification of the porphyrin chromophore by ring fusion: identifying trends due to annelation of the porphyrin nucleus

Syntheses of soluble tetrabenzoporphyrins (TBP) and tetranaphtho[2,3]porphyrins (TNP), with multiple substituents in the conjugated aromatic rings but bearing no substituents in the meso-positions, is reported. Both types of porphyrins were obtained by direct aromatization of precursor porphyrins, annealed with either cyclohexene or dihydronaphthalene fragments. TBPs and TNPs possess powerful absorption bands in the near-infrared (λ = 610−710 nm, e = 100,000−300,000 M-1 cm-1) and exhibit strong luminescence. Free bases and Zn complexes fluoresce with quantum yields of up to 50%, whereas Pd and Pt complexes phosphoresce in solutions at ambient temperatures. Remarkably, the phosphorescence quantum yields of Pd and Pt TBPs reach as high as 20−50%, which places them among the brightest near-infrared phosphors known to date.

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Synthesis and Luminescence of Soluble meso-Unsubstituted Tetrabenzo- and Tetranaphtho[2,3]porphyrins

A new method of synthesis of meso-tetraaryltetranaphtho[2,3]porphyrins (Ar4TNP) has been developed Ar4TNPs with peripheral functional groups are obtained by oxidative aromatization of meso-tetraarylporphyrins in which pyrrole units are fused with either octahydro- or dihydronaphthalene moieties These precursor porphyrins are synthesized in four to five steps from readily available starting materials, such as naphthalene or 1,4-benzoquinone The pathway originating in dihydronaphthalene, ie, the “dialine” route, was found to be superior to the alternative “octaline” route in that it (1) enables the shortening of the overall reaction sequence, (2) has a broader scope in terms of the peripheral substitution in Ar4TNPs, and (3) affords higher yields of the target porphyrins Pd complexes of the synthesized Ar4TNPs exhibit remarkably strong absorption bands at 710−720 nm (e ∼ 200 000 M-1 cm-1) and phosphoresce at room temperature with moderate quantum yields (φ = 2−3%, λmax = 900−1000 nm) The absorption m

Synthesis of Symmetrical Tetraaryltetranaphtho[2,3]porphyrins

The steady-state absorption, fluorescence, and excitation spectra and upper excited-state temporal fluorescence decay profiles of 11 tetrapyrroles in several fluid solvents are presented and analyzed to ascertain the factors that control their S2 population decay times. The S2 lifetimes, which vary by more than 2 orders of magnitude, are controlled exclusively by their rates of radiationless decay. The only important electronic relaxation path is S2−S1 internal conversion, the efficiency of which is near 1.0 in all compounds studied (except CdTPP where it is 0.69). The rate of S1 population rise equals the rate of S2 population decay in all cases. Among the compounds studied, only MgTPP exhibits S2−S1 decay behavior that corresponds to the weak coupling limit of radiationless transition theory; all zinc metalloporphyrins exhibit intermediate to strong coupling. Perdeuteration of ZnTPP produces no significant change in the rate of S2 decay or in the quantum yield of S2−S0 fluorescence, indicating that in-p...

Photophysics of Soret-Excited Tetrapyrroles in Solution. II. Effects of Perdeuteration, Substituent Nature and Position, and Macrocycle Structure and Conformation in Zinc(II) Porphyrins

Zinc complexes of tetrabenzoporphyrin with mono-, di-, tri-, and tetraphenyl substituents at meso-position show elecronic spectra with progressive red shifts from those of tetrabenzoporphyrin zinc complex, and these sifts may be related to ruffling of the macrocycle revealed by crystal structure determination. Fluorescence emissions and basicities of these compounds are also effected by this nonplanarity

Spectroscopic characterizations of meso-phenyl substituted tetrabenzoporphyrin zinc complexes

Staphylococcus aureus can cause many diseases and even death. It's important to detect Staphylococcus aureus rapidly and reliably. The accuracy of a novel test named LAMP in detecting Staphylococcus aureus is unclear. Therefore, a systematic review and meta-analysis were conducted to evaluate the accuracy of the LAMP assay for Staphylococcus aureus detection.Four databases were searched for relevant studies. Meta-DiSc 1.4.0 and Stata 12.0 were used for statistical analysis. At the same time, we used QUADAS-2 to assess the studies we included. Two groups of subgroup analysis were done to differentiate the diagnostic effects of various LAMP tests and in cases of different gold standards.11 studies were identified and 19 2 × 2 contingency tables were extracted in our study. The results showed that both pooled sensitivity and specificity of the LAMP assay were 99% (95% CI 99-100).The LAMP assay demonstrated high sensitivity and specificity in diagnosing Staphylococcus aureus. 

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Evaluation of the loop-mediated isothermal amplification assay for Staphylococcus aureus detection: a systematic review and meta-analysis

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Yu-Ran Chen

Papers

Spectroscopic characterizations of meso-phenyl substituted tetrabenzoporphyrin zinc complexes

Evaluation of the loop-mediated isothermal amplification assay for Staphylococcus aureus detection: a systematic review and meta-analysis

Evaluation of the loop-mediated isothermal amplification assay for Staphylococcus aureus detection: a systematic review and meta-analysis