O₂/pH Multisensor Based on One Phosphorescent Dye

Abstract

A new sensor is described based on a phosphorescent metalloporphyrin dye incorporated in a polymeric membrane, which allows measurement of the two important analytes, oxygen and pH. In such a sensor, the bifunctional dye is quenched by O(2) altering its phosphorescence intensity and lifetime (0-21 kPa O(2)), whereas protonation of the dye causes a major change in the absorption spectrum and also reduces the phosphorescence intensity. As a result, quantification and continuous monitoring of the two analytes can be achieved by (i) simultaneous phosphorescence intensity (O(2), pH) and lifetime (O(2)) measurements and (ii) parallel phosphorescence lifetime (O(2)) and ratiometric absorbance (pH) measurements. Although the first method generally requires sensor calibration in intensity mode, the second provides internal referencing and calibration-free capabilities for both analytes. This approach can be extended to sensing of some other analytes.

Palladium Complexes of Azomethine Derivatives of Porphyrins as Potential Photosensitizers

“…Yield: 0.119 g (90 %). 1 (2). 100 mg (0.16 mmol) of diethyl ether of mesochlorin e 6 was dissolved in 7 ml of benzonitrile.…”

“…Aromatic electronic system of the tetrapyrrole macrocycle determines their unique electronic and optical properties allowing the use of porphyrins as sensors for diagnostics [1][2] and photosensitizers (PS) for the processes of photo-oxidation, in particular, for photodynamic therapy (PDT) of cancer where photosensitized generation of singlet oxygen leads to destruction of tumor tissue during PDT. [3][4][5][6][7][8][9][10] It should be noted that the main advantages of PDT are efficiency, ease of operations and absence of severe side effects and diseases compared to standard methods of treatment.…”

Synthesis of 2-{5-[4-((4-nitrophenyl)diazenyl)phenyl]-1,3,4-oxadiazol-2-ylthio}ethyl acrylate monomer and its application in a dual pH and temperature responsive soluble polymeric sensor

“…Recently, dual or multiple stimuli sensors have been reported, that respond simultaneously and independently to different stimuli, such as oxygen and temperature, [17][18][19] oxygen and carbon dioxide, [20,21] oxygen and pH, [22][23][24][25] pressure and temperature, [26] oxygen, temperature and pH, [27] glucose and temperature, [28] pH and temperature, [29][30][31][32][33][34][35][36] and metal ions and temperature. [37] Among these, stimuli-responsive polymers play an important role by changing their structure and physical properties in response to changes in the environment.…”

Synthesis of the First Azomethine Derivatives of Pd(II) Coproporphyrins I and II

“…[10] The potential use of derivatives of mono-meso-substituted porphyrins and metalloporphyrins as multiparametric sensors for oxygen and H + is one of the main factors driving ever-growing interest in the synthesis of new porphyrin derivatives. [11] The porphyrins have attracted even more attention from researchers in various fields due to their phototherapeutic properties in past two decades. [12][13][14] Porphyrin derivatives and related systems have been used as photosensitizers in cancer phototherapy.…”