Heat-stability study of various insulin types in tropical temperature conditions: New insights towards improving diabetes care
Fig 2
A. HPLC potency determination at T = 0 and after 4 and 12 weeks of continuous temperature cycling (25 to 37°C, conditions reproduced in the laboratory) of the three human insulin formulations used for outpatient management on the field by MSF (NPH/isophane, rapid and mixed insulin). Results are expressed as percentages of concentration determined at T = 0 (n = 9). This graph is representative of the situation for all studied formulations, for which the data is reported in Table 1. B: Comparison between HPLC potency determination of the same mixed insulin as in Fig 2A exposed to 4 weeks of continuous temperature cycling and two samples of mixed insulin that came back from Kenya after 4 weeks of storage at ambient temperature at a patient’s home. Results are expressed as percentages of insulin concentration of the reference kept at 2–8°C (mixed insulin; n = 9).