| 摘要 |
A test means, test device, and method for determining the ionic strength or specific gravity of a test sample as well as a method for making the device, are disclosed. The test means comprises a weakly acidic polyelectrolyte polymer, at least 50 percent of the carboxyl groups of which are present in the form of the salt of a quaternary ammonium ion having the structure <IMAGE> in which the R substituents, same or different, are hydrogen, lower alkyl or aryl, with the proviso that at least one of R is other than hydrogen; and an indicator means capable of producing a detectable response to ion exchange between the polyelectrolyte salt and the test sample. The device comprises a carrier matrix incorporated with the test means. The method for determining the ionic strength or specific gravity comprises contacting the test sample with the test means or device and observing a detectable response. The method for making the device comprises the steps of reacting the weakly acidic polyelectrolyte polymer with sufficient quaternary ammonium hydroxide to neutralize at least 50 percent of the carboxyl groups to form a polyelectrolyte salt, and incorporating the salt and a pH indicator with a carrier matrix. |
