<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>Ultrasound analysis of implants. (a) 2D images of microsphere implants, with the degradation crosslink modulator -CN (<i>ε</i>-Lys), showing the widest cross-section at 0, 1700, and 5880 hours post injection, and the time relative to <i>in vitro</i> reverse degelation time (<span class="nowrap"><svg height="12.5977pt" id="M82" style="vertical-align:-3.30937pt" version="1.1" viewbox="-0.0498162 -9.28833 55.4764 12.5977" width="55.4764pt" 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="M324 430H196L233 583L223 592L145 529L120 430H54L29 396L31 388H111L56 126C33 15 54 -12 77 -12C137 -12 214 57 250 95L233 119C208 92 155 59 138 59C126 59 120 70 131 125L186 390L298 394L324 430Z"></path></g><g transform="matrix(.013,0,0,-0.013,4.433,0)"><path d="M368 703H309L44 -163H104L368 703Z"></path></g><g transform="matrix(.013,0,0,-0.013,9.794,0)"><path d="M324 430H196L233 583L223 592L145 529L120 430H54L29 396L31 388H111L56 126C33 15 54 -12 77 -12C137 -12 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width="43.143pt" 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="M152 404V712C115 698 54 683 7 677V654C71 648 73 642 73 579V24C128 -2 179 -12 220 -12C353 -12 471 92 471 238C471 357 381 449 274 449C262 449 249 446 233 439L152 404ZM152 374C170 384 202 393 230 393C313 393 382 326 382 213C382 97 330 26 246 26C194 26 165 62 158 81C154 91 152 101 152 116V374Z"></path></g><g transform="matrix(.013,0,0,-0.013,6.669,0)"><path d="M433 39L423 65C413 59 399 54 387 54C370 54 352 69 352 114V299C352 352 342 392 307 422C285 440 255 449 225 449C168 437 102 399 75 379C56 365 44 353 44 339C44 315 69 296 87 296C101 296 111 303 116 319C124 349 133 371 145 385C156 397 171 404 190 404C241 404 275 364 275 291V274C253 256 180 229 120 209C65 190 39 159 39 110C39 47 88 -12 159 -12C189 -12 237 25 277 52C282 35 288 21 301 8C312 -3 333 -12 348 -12L433 39ZM275 84C256 65 221 48 195 48C164 48 124 73 124 124C124 161 146 180 185 198C206 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(b) 3D USCT renderings showing the volumes of the implants shown in (a).</div>

International Journal of Polymer Science

fig7

Figure 7

Figure 7: <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 7