Fig. 2. In vitro activities of functionalized inositol phosphates.
a Compounds were tested in an in vitro serum calcification propensity assay. T50 is defined as the time at which 50% of CPP1 is transformed to CPP2. The concentration necessary to delay T50 to 350 min (dotted line) was used to compare the compounds’ activities (n = 4 for myo-inositol, n = 6 for (OEG2)2-IP4, and n = 26 for IP6). b Representative TEM images and corresponding selected area electron diffraction patterns of CPPs, showing the predominant presence of spherical-shaped CPP1s and spindle-shaped CPP2s after incubation with 100 µM (OEG2)2-IP4 and IP6, respectively for 14 h at 37 °C (scale bar = 50 nm). c Competitive 18F-NaF-binding assay to characterize interaction of compounds with CPPs (n = 3). d Phytase hydrolysis of compounds (n = 3). e Activity in the serum calcification propensity assay after incubation in enzymatically active human serum for 4.5 h at 37 °C (n = 4). All data are expressed as mean ± s.d. from n independent experiments. Statistical significance was calculated from a paired Student’s t-test, ***p < 0.001 vs. baseline T50.