<i>In Vitro-In Vivo</i> Correlation for the Degradation of Tetra-PEG Hydrogel Microspheres with Tunable <i>β</i>-Eliminative Crosslink Cleavage Rates

<div>Injections of microspheres in the rat. (a) Temporal sequence of eight injections of microspheres in the rat spaced in intervals of approximately <span class="nowrap"><svg height="12.5977pt" id="M14" style="vertical-align:-3.30937pt" version="1.1" viewbox="-0.0498162 -9.28833 86.0539 12.5977" width="86.0539pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z"></path></g><g transform="matrix(.013,0,0,-0.013,4.498,0)"><path d="M285 378C315 398 338 416 353 432C373 451 384 474 384 503C384 579 325 635 236 635H235C182 635 136 610 108 579L65 516L85 496C110 533 150 575 205 575C258 575 300 543 300 481C300 407 232 369 141 339L147 310C163 315 188 321 211 321C268 321 338 284 338 192C338 94 288 40 217 40C160 40 119 68 93 91C85 98 77 97 69 91C60 84 47 71 46 58C44 46 48 35 62 22C75 10 116 -12 162 -12C234 -12 424 62 424 224C424 297 373 359 285 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is an untreated control site for background fluorescence determination. (b) Photograph of tattoo-marked SC injection sites labeled 1, 3, 5, and 7 at termination of the experiment where 1 is the oldest injection with almost completely degraded microspheres and 7 is the newest injection with fully intact microspheres. Tattoo circles are approximately 12 mm in diameter.</div>

International Journal of Polymer Science

fig5

Figure 5

Figure 5: <i>In Vitro-In Vivo</i> Correlation for the Degradation of Tetra-PEG Hydrogel Microspheres with Tunable <i>β</i>-Eliminative Crosslink Cleavage Rates 

International Journal of Polymer Science

In Vitro-In Vivo Correlation for the Degradation of Tetra-PEG Hydrogel Microspheres with Tunable β-Eliminative Crosslink Cleavage Rates

Figure 5