Contamination of distilled water, HCl, and NH4OH with amino acids, proteins, and bacteria.

Contamination of distilled water with free and bound amino acids and with microbes has been overlooked in most laboratories.Unless special precautions are taken, distilledwater will be contaminated with airborne microbes, probably psuedomoriads, which multiply in water of conductivity quality. Amino acids and proteins that may be found in the water therefore presumably are derived from these airborne organisms. Chemical reagents such as hydrochloric acid and ammonium hydroxide solutions, which have water as an integral part, also have been found to be contaminated with amino acids. This paper deals with the extent of such contamination and describes means to provide water and hydrochloric acid (6 mol/liter) that would be suitable for determination of amino acids in concentrations of iOmol/liter or less in materials of biological interest as well as rocks, lunar soil, meteorites, etc.