Further development on DMFC device used for analytical purpose: real applications in the pharmaceutical field and possible in biological fluids

Abstract

The analytical research devoted to the utilization of the direct methanol fuel cell (DMFC) for analytical purposes has been continued. The research reported in this paper concerns two points, one of which was the possibility of improving the features, from the analytical point of view, of a catalytic fuel cell for methanol and ethanol, by introducing an enzyme, immobilized into a dialysis membrane small bag, in the anodic area of the fuel cell. This objective has been fully achieved, particularly using the enzyme alcohol dehydrogenase, which has increased the sensitivity of the method and reduced dramatically the response time of the cell. The second point concerned the opportunity to determine two particular antibiotics having an alcohol functional group in their molecule, that is, imipenem and chloramphenicol. Also, this goal has been reached, even if the sensitivity of the method is not so high. Graphical abstract Imipenem and Chloramphenicol determination using the DMFC and Ethanol determination using the enzymatic DMFC.

Study for developing an electronic tongue to discriminate three different classes of waters, by using common sensors and the principal component analysis

“…The hydrogen ions permeated the Nafion membrane and reacted with the oxygen to the cathodic section of the cell, giving water; this process generated a difference of potential between the anode and the cathode. To reduce the response time of the fuel cell, an immobilised enzyme (alcohol dehydrogenase) was introduced in the anodic section of the fuel cell (as described in detail in previous papers [16,17]). At present, we have not immobilised the enzyme inside the bag with a chemical method, even if this is of course possible and not too difficult [23], as it is enough to easy replace the exhausted enzyme in the bag, so that the enzyme resume to operate at its best.…”

“…At present, we have not immobilised the enzyme inside the bag with a chemical method, even if this is of course possible and not too difficult [23], as it is enough to easy replace the exhausted enzyme in the bag, so that the enzyme resume to operate at its best. It was recorded the supplied current (SC) of the fuel cell, at the optimised applied potential [16,17]. The measurement of the SC, at the steady state was read off and correlated with the alcohol concentration in the fuel cell [16,17].…”

“…It was recorded the supplied current (SC) of the fuel cell, at the optimised applied potential [16,17]. The measurement of the SC, at the steady state was read off and correlated with the alcohol concentration in the fuel cell [16,17].…”

“…The fuel cell frame was made in Plexiglas ® , while the electrode end plate was made in Pt-Ru black catalyst assembled with Nafion ™ membrane. For potentiostatic format measurement [16,17], Palmsens mod. EmStat potentiostat was used, connected to the fuel cell.…”

“…Furthermore, in the majority of these articles, chemometric methods for the elaboration of experimental measurements, have been used, classic [4,[6][7][8][9][10][11][12][13][14][15] or quite complex [3,5,11]. The present research on the contrary was conducted using easy, but proved effective methodologies, more in particular have been employed: a glass potentiometric electrode for the pH measurement, an amperometric gaseous diffusion electrode (Clark type) for measuring the dissolved oxygen content, a temperature sensor and, finally, a sensor for measuring the concentration of alcoholic traces of ethanol (and methanol, if eventually present), that we have recently developed, consisting of a small enzymatic catalytic fuel cell for methanol and ethanol [16,17]. This latter type of sensor has been chosen by us because, the pollution from ethanol of natural waters, especially the groundwater, is now an increasingly sensitive problem.…”