Page 62 - Cellular Imaging in Regenerative Medicine, Cancer and Osteoarthritis
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Chapter 3
Figure 3 R2* relaxation rate (1/s) plotted against iron concentration cFe (mM). Linear fit on data is shown. Relaxivity values (slope of linear fitted curve) are shown next to linear fits (in units: mM-1 s-1). Free super paramagnetic iron oxide particles (SPIO), SPIO complex (SPIOc) and MPIO dilution series exhibit different relaxivities (r2*); r2* is higher for particles of higher Fe content. Cells labeled with SPIOc exhibit higher r2* than SPIOc dilutions. Cell division series (initially labeled and harvested at increasing delay times) and cell dilution series (mixture of labeled and unlabeled cells) exhibit different r2*. Cell density is identical for all cell-containing samples.
Figure 4 R2’ relaxation rate (1/s) plotted against iron concentration cFe (mM). Relaxivity values are shown next to linear fits (in units: mM-1 s-1). Preparation of samples is identical to that in Fig. 3. R2’ differentiates between intra- and extracellular super paramagnetic iron oxide particles (SPIO). r2’ ≈ 0 for free SPIO and SPIOc. MPIO and cell dilutions have very close r2’ values. For cell division and cell dilution samples, r2’ values are different.
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