Simplified Fabrication for Ion-Selective Optical Emulsion Sensor with Hydrophobic Solvatochromic Dye Transducer: A Cautionary Tale

Wang, Lu1; Sadler, Stephanie1; Cao, Tianchi1; Xie, Xiaojiang2; Von Filseck, Joachim Moser3; Bakker, Eric1

2019-07-16

10.1021/acs.analchem.9b01145

ANALYTICAL CHEMISTRY   影响因子和分区

0003-2700

1520-6882

It has recently been reported that polystyrene microbeads may be modified to realize plasticizer-free ion selective optical sensors (optodes) on the basis of solvatochromic dye transducers. We show here that the functionalized microbeads, individually isolated by flow cytometry, exhibit unexpectedly poor fluorescent properties and that the sensor response is instead attributed to the supernatant. A more thorough study reveals that such optical microemulsion sensors can be made operationally functional and chemically selective, seemingly in the absence of any solvent matrix or added surfactant. Instead, it is shown that residual THF used in the fabrication of the emulsified sensors may solubilize the sensing components and give a functional optode response. To evaluate this further, the number of sensing components was stepwise simplified to assess their need. Variation of residual THF levels has no effect on the ion optode response when plasticizer is present, in support of established results. Lipophilic solvatochromic dye transducers are also shown not to require an added surfactant as their nature already endows the emulsified sensors with a stabilizing ionic surface charge. The ionophores are shown to exhibit much larger stability constants in the surfactant-free formulations than surfactant-based ones (valionomycin, log beta > 9.2 compared to 6.1; Na+-ionophore X, 6.7 vs 4.7), which is attributed to a less polar solvent environment for the ionophore. Potassium-, sodium-, and calcium-selective sensors were used as model systems in this study.

SCI ; EI

英语

NI期刊

其他

Chemistry

Chemistry, Analytical

WOS:000476567700035

AMER CHEMICAL SOC

20193207292333

Emulsification ; Fabrication ; Ionophores ; Ions ; Microbeads ; Microemulsions ; Plasticizers ; Reinforced plastics ; Transducers

Chemical Operations:802.3 ; Chemical Agents and Basic Industrial Chemicals:803 ; Chemical Products Generally:804 ; Polymer Products:817.1

CHEMISTRY

Web of Science

1.Univ Geneva, Dept Inorgan & Analyt Chem, Quai Ernest Ansermet 30, CH-1211 Geneva 4, Switzerland
2.Southern Univ Sci & Technol, Dept Chem, 1088 Xueyuan Rd, Shenzhen 518055, Guangdong, Peoples R China
3.Univ Geneva, Biochem Dept, Quai Ernest Ansermet 30, CH-1211 Geneva 4, Switzerland

Wang, Lu,Sadler, Stephanie,Cao, Tianchi,et al. Simplified Fabrication for Ion-Selective Optical Emulsion Sensor with Hydrophobic Solvatochromic Dye Transducer: A Cautionary Tale[J]. ANALYTICAL CHEMISTRY,2019,91(14):8973-8978.

Wang, Lu,Sadler, Stephanie,Cao, Tianchi,Xie, Xiaojiang,Von Filseck, Joachim Moser,&Bakker, Eric.(2019).Simplified Fabrication for Ion-Selective Optical Emulsion Sensor with Hydrophobic Solvatochromic Dye Transducer: A Cautionary Tale.ANALYTICAL CHEMISTRY,91(14),8973-8978.

Wang, Lu,et al."Simplified Fabrication for Ion-Selective Optical Emulsion Sensor with Hydrophobic Solvatochromic Dye Transducer: A Cautionary Tale".ANALYTICAL CHEMISTRY 91.14(2019):8973-8978.