 The objective of this study is to ascertain the systemic exposure of the active ingredient in Granexin gel aCT1 peptide after topical application to diabetic foot ulcers using pharmacokinetic analysis. It is planned that a total of 16 patients with diabetic foot ulcers will receive Granexin gel treatment plus standard of care in this one arm study. The study includes a screening period 1 week and a treatment period 1 week which occur sequentially for a given patient. The baseline day, which demarcates the beginning of the treatment period, is the designated as Day 0. Screening procedures are initially conducted on Day -7. 