| 摘要 |
Investigating a membrane-enclosed biological compartment (1), prepared in a microfluid chamber (2) through which a culture medium, in contact with (1) and optionally containing a substance that affects (1), can flow, by measuring pH in the medium. Investigating a membrane-enclosed biological compartment (1). The concentration of a substance (A), released and/or consumed by the metabolism of (1), is measured indirectly in a region of the medium affected by (1) by applying an electrical potential between working electrode (19) in the specified region, and reference electrode (20), spaced from (19), so that hydroxide or hydrogen ions are formed from (A) in the medium. During application of the potential, at least one pH measurement (M1) is taken from the medium in the specified region, then the potential is turned off, or altered, so that formation of the ions stops. Shortly before or after measuring M1, a second pH measurement (M2) is taken, without applied potential or at a potential that suppresses formation of the ions, and the difference between M1 and M2 ( DELTA M) is determined. The procedure is repeated at least once and steps (i) and (ii) are carried out: (i) the change in concentration of (A) in the medium is determined from difference between at least two DELTA M; and (ii) the acidification/basification of the medium is determined from the difference between at least two M1 and/or M2 values. From the results of (i) and (ii), the metabolic activity of (1) is determined. |
