Effect of a dextrane and hydrophilizing substances on the properties of thermosensitive hydrophilic gels containing lactic acid complexed with chitosan

Gels containing lactic acid complexed with chitosan at a stechiometric ratio 1:1 and 2:1 and 5-25% content of PEG-200 reveal pH from 3.42 to 4.95. The addition of 20 – 25% poloxamer 407 increases the pH from 4.55 to 5.30 for 1:1 gels and from 4.00 to 4.85 for 2:1 gels. The addition of 1.0% dextrane decreases the pH of investigated gels from 4.40 to 4.90 (1:1) and from 4.00 to 4.48 (2:1). The addition of poloxamer 407 at concentrations of 20 to 25% increases the dynamic viscosity from 506.14 to 641.20 for 1:1 and from 540.35 to 692.55 for 2:1 ratios. The addition of 1.0% dextrane increases the dynamic viscosity from 665.23 to 750.28 for 1:1 and from 645.50 to 740.16 for 2:1 ratios. The addition of dextrane and glycerol or 1,2-propylene glycol reduces the pH and maintains high adhesion. The use of dextrane and hydrophilizing substances allowed to obtain physiological range pH.