A new needle-type colloid osmometer for continuous determination of blood oncotic pressure

For the purpose of facilitating measurement of colloid osmotic pressure of body fluids, a new needle-type colloid osmometer which uses a hollow fiber as a semipermeable membrane instead of a sheet ultrafilter was developed. The simple construction, easy production, and satisfactory performance of the osmometer are described in detail. Although hydrostatic pressure existing in the sample interfered a little with the accuracy of measurement, quickly interchangeable sensing probes brought great advantages in practice.