Analysis of Heparin – Azure A Metachromasy in Agarose Gel
The effect of changes in pH, temperature, salt, and ethanol concentrations on the metachromatic heparin – azure A complex was studied in solution and in agarose gel photometrically. Salt, ethanol, and low pH inhibit the heparin – azure A interaction. With low salt concentration the inhibition is greater in aqueous solution than in agarose gel. Increasing ethanol concentrations interfere stepwise, with a plateau between 40–80% ethanol. Visual estimates of metachromasy do not coincide with the photometric measurements. Increase in temperature decreases the heparin – azure A complex in agarose. The responses to the parameter changes are similar in both media, with differences attributable to the different physical states.