Metalloporphyrins immobilized in styrene–trifluoroethylmethacrylate copolymer film as an optical oxygen sensing probe

Abstract

A series of new fluoropolymer, poly(styrene-co-trifluoroethylmethacrylate) (poly-Sty n -co-TFEM m ), with different composition ratios of Sty and TFEM units, is synthesized and applied to the matrix of an optical oxygen sensing probe using phosphorescence quenching of metalloporphyrins, platinum and palladium octaethylporphyrin (PtOEP and PdOEP), by oxygen. The phosphorescence intensity of PtOEP and PdOEP in poly-Sty n -co-TFEM m film decreased with increase of oxygen concentration. The ratio I 0 /I 100 is used as a sensitivity of the sensing film, where I 0 and I 100 represent the detected phosphorescence intensities from a film exposed to 100% argon and 100% oxygen, respectively. For PtOEP in poly-Sty n -co-TFEM m film, I 0 /I 100 ratios are more than 20.6 and large Stern-Volmer constants greater than 0.49% À1 are obtained compared with PtOEP in PS film. For PdOEP in poly-Sty n -co-TFEM m film, on the other hand, large I 0 /I 100 values greater than 188.7 are obtained. In both cases for PtOEP and PdOEP, I 0 / I 100 values increased with increase of the number of TFEM units in poly-Sty n -co-TFEM m . The response times of PtOEP and PdOEP immobilized in poly-Sty 1 -co-TFEM 2.50 films are 5.5 and 3.0 s on going from argon to oxygen and 90.0 and 143 s from oxygen to argon, respectively. These results show that PtOEP and PdOEP immobilized in polySty n -co-TFEM m films are highly sensitive devices for oxygen.

Optical methods for sensing and imaging oxygen: materials, spectroscopies and applications

“…432 The probe PtOEP displays extremely high sensitivities to oxygen, with an I 0 /I 100 of 288 and 296 for poly-IBM-co-TFEM and poly-styrene-co-TFEM, respectively. 321,342 The sensing films are fairly photostable and have response times of B5 s. Schanze et al 172 replaced the styrene monomer by 4-tert-butylstyrene (tBS) and copolymerized it with TFEM to obtain the copolymer poly-tBS-co-TFEM with even higher gas permeability than poly-styrene-co-TFEM, and the immobilized probe PtTFPP also displays very high sensitivity.…”

“…The C-F chemical bond is short and strong (with a binding energy of 116 kcal mol À1 ), and the fluoropolymers therefore are quite resistant toward photooxidation. The group of Amao 431 has developed several fluoropolymers for oxygen sensing with extremely high sensitivity, these include poly(styrene-co-pentafluorostyrene), 322 poly(styrene)-co-(trifluoroethyl methacrylate) (''poly-styrene-co-TFEM''), 321,342 poly(isobutyl methacrylate)-co-(trifluoroethyl methacrylate) (''poly-IBM-co-TFEM''), 432 and fluorinated poly(aryl ether ketone). 329 They observed that the sensitivity of the polymer increased with the degree of fluorination and that the use of fluoropolymers generally leads to low limits of detection and more rapid response.…”

Ratiometric optical oxygen sensing: a review in respect of material design

“…22,25 However, most of them exhibit weak phosphorescence and absorption maxima in the UV or blue spectral region, resulting in the requirement of high-energy excitation light sources and detectors. On the other hand, intensely luminescent metal complexes such as metalloporphyrins [Pt(II) (10)(11)(12) and Pd(II)-porphyrin complexes], [48][49][50][51][52][53][54] polypyridyl transition metal complexes [Ru(II) (13-15), [55][56][57][58][59][60] Pt(II) (16,17), [61][62][63][64] Ir(III) (18,19), [65][66][67][68][69][70][71] Re(I), 72,73 Os(II), 74,75 and Cu(I) complexes (20) [76][77][78][79][80] ], and lanthanide complexes [81][82][83] exhibit very desirable features in terms of their richer excited states, larger Stokes' shifts, long decay lifetimes, high luminescence quantum yields, and high stability, for the purpose of oxygen sensing. Among the phosphores...…”

Development of a Ratiometric Fluorescent Glucose Sensor Using an Oxygen-Sensing Membrane Immobilized with Glucose Oxidase for the Detection of Glucose in Tears

“…Fluorescence is also combined with the enzyme GOD to change the fluorescence state through energy transfer between the flavin group (FAD) of GOD and fluorescein-5(6)-carboxamidocaproic acid n-succinimidyl ester during glucose measurement [ 9 ]. In addition, the concept of glucose detection based on oxygen consumption in the glucose oxidation reaction under the catalysis of GOD is exploited since many fluorescent oxygen sensors are recently developed [ 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 ]. However, there is a need for a less invasive method to self-monitor glucose levels for diabetes patients [ 18 ].…”