Miniaturized pH biosensors based on electrochemically modified electrodes with biocompatible polymers.
Potentiometric pH sensors based on linear polyethylenimine (L-PEI) and linear polypropylenimine(L-PPI), two synthetic enzymes and biocompatible polymers, films were prepared by electropolymerization of three different monomers: ethylenediamine (EDA), 1,3-diaminopropane (1,3-DAP) and diethylenetriamine (DETA) in order to be used in clinical, dermatological and biological applications, such as in vivo analysis. In a first step a biosensor was tested which consisted in a platinum wire protruded from glass sheath. The polymer film coated on these platinum electrodes showed good linear potentiometric responses to pH changes from pH 3 to 10. Resulting electrodes present both good reversibility and good stability versus time. The effect of the different polymer film thicknesses to potentiometric responses was also studied. This study allowed us to develop a miniaturized pH biosensor in the second step. This sensor was fabricated using photo-lithography, followed by sputtering and lift-off processes, and it included an electronic detection system. We have also successfully studied the potentiometric responses to pH changes of this device over a period of 1 month, and so we propose this new pH micro-biosensor as an alternative to classical pH sensors currently used in dermatology.
Lakard
Boris
B
LCMI, UFR Sciences, Université de Franche-Comté, 16 route de Gray, Besançon 25030, France. boris.lakard@univ-fcomte.fr
Herlem
Guillaume
G
de Labachelerie
Michel
M
Daniau
William
W
Martin
Gilles
G
Jeannot
Jean Claude
JC
Robert
Laurent
L
Fahys
Bernard
B
D001672:Biocompatible Materials / Q000138:chemical synthesis / Q000737:chemistry*; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004566:Electrodes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006863:Hydrogen-Ion Concentration; D008904:Miniaturization; D011094:Polyethyleneimine / Q000737:chemistry*; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry; D011126:Polypropylenes / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013499:Surface Properties
D001672:Biocompatible Materials; D011108:Polymers; D011126:Polypropylenes; C443641:poly(propyleneimine); D011094:Polyethyleneimine