Measuring ion strength of electrolyte

摘要

Process and appts. for measuring directly the ion strength of an electrolyte, which are applicable partic. to biological e.g. metabolic processes, require the pH-value of the electrolyte to be measured by two indicators which are dependent in different ways on the ion strength. The ion strength is calculated from the approximation (I) where I= Ion strength Io= Ion strength on calibration pH1 (N)= pH value measured by one indicator N pH1(X)= pH value measured by the second indicator W(N)= valence of first indicator W(X)= valence of second indicator, and where F(N) is - 1/007(2w(N)+1).Pref. the indicators are fluorescence indicators and an associated reference indicator is used to eliminate intensity fluctuations. The indicators are pref. hydroxypyrentrisulphonate (HPTS) and b-methylumbelliferon (b-M).Measurement can be made of mixts. in an unknown compsn