Potentiometric combination ion-carbon dioxide sensors for in vitro and in vivo blood measurements

Abstract

The development and analytical performance of a novel potentiometric combination ion/pCO2 sensor design for in vitro and in vivo measurements are reported. The design is based on incorporating an appropriate ionophore within the outer silicone gas permeable membranes of both conventional macro and new catheter-type pCO2 sensors. Simultaneous measurement of the potentials across the ion-selective/gas permeable membrane and the inner glass or polymer pH sensitive membrane provides the basis for continuous monitoring of both ionic and pCO2 levels with the same device. A macro-sized K+/pCO2 embodiment of the sensor is constructed from a commercial Severinghaus CO2 sensor and is used to demonstrate the principles and capabilities of the proposed design. A flexible, miniaturized (outer diameter = 1.2 mm) combination K+/pCO2 catheter sensor is also described. The catheter-type sensor is fabricated by inserting a tubular polymer membrane pH electrode into an outer silicone rubber tube doped with valinomycin. Continuous measurements of K+ and pCO2 during 6-h blood pump studies using both the macro and catheter-type combination sensors correlate well with those of conventional bench-top analyzers. In addition, continuous (4 h) intravascular measurements with the combination catheter sensor in dogs show good agreement with those of commercial blood analyzers (R = 0.984 and 0.962 for pCO2 and K+, respectively.

Vibrational spectroscopic studies of sol–gel derived physical and chemical bonded ORMOSILs

“…molecular level homogeneity, purity, large flexibility in processing and low processing temperature. Hence, these hybrids find tremendous scopes in various industrial applications [1,2]. The physical bonded silica-poly(ethylene glycol) [SiO 2 -PEG] hybrid system, synthesized by traditional route of sol-gel method, has been studied by various research groups due to its excellent optical properties [3][4][5][6][7][8][9][10][11].…”

Hybrid aniline/silica xerogel cation adsorption and thermodynamics of interaction

“…The great interest in these materials is due to their novel properties resulting from the combination of organic and inorganic phases [13,14]. In addition, the great advantage of the sol-gel method is the fact that reactions can be carried out at room temperature and also the possibility of incorporating some desirable physical structural properties such as porosity, surface area, pore size distribution, organic loading, and pore diameters, parameters that are derived from the synthetic desirable methodology employed [15], especially because there is a great possibility of controlling proprieties of the hybrid materials prepared from the sol-gel method, enabling them to be used in different analytical applications [16][17][18].…”

Ion‐Selective Electrodes: Fundamentals

“…pH and carbon dioxide. 141,142 The further development of ISE arrays for simultaneous multitarget determinations will continue. 143,144 This also includes methods of microfabrication.…”