2.3. In vitro study of the release of gentamicin sulfate
The controlled release of gentamicin sulfate was studied afterimmersion of scaffolds of 300 mg (±5 mg) in 10 mL of a physiologi-cal saline solution (BioWhittaker®Dulbecco’s PBS) without calciumand magnesium to avoid the chemical reaction of bioactivity. Itsbuffering capacity is based on the dihydrogen/hydrogen pair whichis also one of three major mechanisms for maintaining blood pH:
HPO4
2- + H+ =
H2PO4
-
The release of gentamicin sulfate was studied after 5, 10, 20,30 min and 1, 2, 6 h in triplicate. These notices were chosen becausesome studies have proved that gentamicin sulfate is releasedquickly [18–28].
PBS solutions were analyzed at 256 nm using UVspectrophotometer (Jenway 6705) to measure the concentrationof gentamicin sulfate.
The blank control is 10 mL of PBS withoutmaterials and the calibration curve was plotted using standardssolutions of increasing concentrations of gentamicin sulfate from 1to 30 mg mL−1.
The results were averaged with standard deviation.