For instance, changes in scattering properties have previously been utilized to study 2D lipid bilayer formation and phase transitions. Following CDSA, the platelet perimeter remains active for the templated edge-directed growth of additional platelet area. Therefore, multiannulus platelets can be prepared by sequential unimer addition. The growth occurs radially from the edges of the platelets, with each successive annulus extending the preceding one. By varying the unimer composition, the composition/thickness of each annulus can be adjusted, which allows us to utilize the contrast mechanism of iSCAT to investigate the kinetics and properties of individual annuli during platelet assembly. still identifiable (to clarify the boundaries, each annulus was color-coded as shown in Fig. ). The outermost boundary within each annulus appears discernibly darker (with a larger negative contrast) compared to the center. We speculate that this effect is potentially caused by a nonuniform distribution of PCL 45 and PCL 45 -b-PDMA 348 within each annulus due to differences in their crystallization rates. However, although providing some contrast variations, this effect was insufficient to render significant changes in growth kinetics. Fig. illustrates the progression of averaged platelet area (calculated from averaging three 3-annulus platelets displayed in Fig. ), with each successive unimer addition synchronized to the corresponding time of addition. The rate constants extracted for each annulus were essentially unchanged from those in Fig. . As expected, a higher unimer concentration resulted in a faster assembly rate. As a result, besides the dimensional and morphological information, iSCAT can also probe into the nanoscopic surface information of individual platelets based on their contrast variations.