[Photometric control of the presence of potassium benzylpenicillin crystals after centrifugation].

A photometric (turbidimetric) method was proposed for automatic control of the content of potassium benzylpenicillin crystals after centrifugation. The optical properties of the technological media were studied. It was found that along with intensive absorption in the UV spectrum due to the presence of the penicillin and its degradation products the solutions absorbed the light of the visible spectrum (400-700 nm). Therefore, determination of the penicillin crystal concentration by light dispersion in the UV and visible spectra was possible only with a differential procedure. For the near IR region there were defined areas at 930-950, 1020-1080 and 1200-1260 nm without self-absorption of the solutions providing the use of the one-canal measurement scheme. Procedures for determining the presence of penicillin crystals by light dispersion were developed: differential procedures in the visible spectrum (490 nm) and the near IR region (940-980 nm). The use of market photometers for realization of the procedures was recommended.