Cell Bioelectrochemistry: Past, Present, and Future
Bioelectrochemistry is an important field in biology and bioengineering because it
involves the study of fundamental biological activities such as signal transduction andenergy production. In the late 18th century, several giants in electrochemistry madehistorical progress in bioelectrochemistry. In this period, two of these giants, Luigi
Galvani and Alessandro Volta, disputed over the so-called frog experiments, where frog
legs were found to twitch if in contact with an iron fence. After a long debate, the muscletwitches were recognized to be induced by the current flowing between two dissimilar
metals. Johann Wilhelm Ritter was inspired by this debate and performed experiments on
his own body by using high voltage. This debate and related experiments called a great
deal of attention from various fields, and the importance of electrochemical processes inliving beings was realized. The series of outstanding scientific activities brought about
opening the new era of bioelectrochemistry.
During the last 200 years, bioelectrochemistry has widened its territory byincorporating various research fields in both fundamental and applied cell biology andbioengineering. In fundamental research, bioelectrochemistry has made important
contributions in understanding cell bioenergetics: the key process in energy production
by respiration and photosynthesis is biological electron transport. Many membrane
phenomena are electrochemical processes; membrane potential is the driving force of
signal transduction in the nervous system and of membrane transport. Electrochemicalmeasurements have been extensively employed to characterize basic functions of proteinsand biomolecules that are closely related with cell activities. Because of the fundamental
importance of cell bioelectrochemistry, many researchers involved in this field have been
awarded Nobel Prize, including Alan Lloyd Hodgkin, Andrew Fielding Huxley, and Sir
John Carew Eccles in 1963 for elucidating the ionic mechanism of the cell membrane andErwin Neher and Bert Sakmann in 1991 for discovering the function of single ionchannels in cells.
In applied research, bioelectrochemistry has made significant contributions tomodern biotechnology. The electrochemical biosensor is the most successful applicationof bioelectrochemistry. Nowadays, an amperometric glucose-monitoring sensor isessential for patients with diabetes to ensure a healthy daily life. As next-generationbiosensors, many researchers have developed various cell-based biosensors by using
bacteria, plant, and mammalian cells, some of which have been used in medical, health,environmental, and food-safety fields. Currently, the fields of cell engineering andbioenergy are being extensively investigated. Furthermore, micro-/nano-electrochemical

devices and systems have been developed and applied to characterization of live cells
It is difficult to predict the future direction of cell bioelectrochemistry research.
However, the progression of research from simple to complex and from isolated toaggregated system (three- and four-dimensional) should be continued to further
strengthen bioelectrochemistry. We must take into account long-term and bird’s-eye
perspectives, conduct interdisciplinary collaboration, and incorporate advanced andsophisticated technologies and tools from other areas. I am convinced that the future ofcell bioelectrochemistry is bright. Cell bioelectrochemistry will remain an indispensablearea in fundamental biology and will continue to play a major role in the future
development of advanced biosensors, artificial biosystems, and bioelectronics andproduction of fine biochemicals and biomaterials.