Freezing-Point Depressions of Hoagland's ‘Carbowax’ Systems

Abstract

SOLUTIONS of various osmotic pressures have been widely used in biology. Sugars and their derivatives, commonly used to maintain osmotic pressures, have the drawback that many, if not all, of these compounds can be metabolized by the test tissue or organism. McClenden and Blinks¹ described the use of ‘Carbowax 4000’ (polyethylene glycol) in maintaining various osmotic concentrations in a study of the Hill reaction. Excellent results were reported. This laboratory has successfully used ‘Carbowax 4000’ in a study of water uptake by bush beans, Phaseolus vulgaris. We believe our results on freezing point depressions of complete Hoagland's solutions containing various concentrations of ‘Carbowax 4000’ may be of value to other investigators.