Molecular Dynamics of POPC Phospholipid Bilayers through the Gel to Fluid Phase Transition: An Incoherent Quasi-Elastic Neutron Scattering Study

<div>(a) <svg height="10.9432pt" id="M111" style="vertical-align:-2.2029pt" version="1.1" viewbox="-0.0498162 -8.7403 9.9906 10.9432" width="9.9906pt" 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="M734 -137C662 -100 567 -37 503 8C623 45 724 166 724 333C724 530 575 665 393 665C162 665 42 496 42 319C42 232 74 149 131 87C187 26 281 -9 343 -13C470 -114 547 -148 579 -156C617 -166 676 -172 726 -164L734 -137ZM358 30C254 60 195 186 195 343S263 623 372 623C491 623 571 502 571 303C571 139 512 56 466 37C458 43 449 50 440 56L358 30Z" id="g13-79"></path></g></svg>-dependence of the experimental <svg height="12.0621pt" id="M112" style="vertical-align:-3.2957pt" version="1.1" viewbox="-0.0498162 -8.7664 42.2062 12.0621" width="42.2062pt" 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="M517 162C503 123 484 88 467 68C445 42 417 34 341 34C291 34 256 34 237 47C219 59 213 81 213 128V317H308C395 317 402 311 415 240H444V431H415C403 364 398 356 307 356H213V584C213 613 215 616 246 616H322C394 616 421 609 435 587C448 566 458 544 467 502L496 506C493 557 488 625 488 650H42V622C120 616 128 612 128 523V125C128 43 120 35 29 28V0H511C520 31 540 125 546 158L517 162Z" id="g121-67"></path></g><g transform="matrix(.013,0,0,-0.013,7.384,0)"><path d="M303 0V28C221 34 213 39 213 125V525C213 610 221 616 303 622V650H38V622C120 616 128 610 128 525V125C128 40 120 34 38 28V0H303Z" id="g121-71"></path></g><g transform="matrix(.013,0,0,-0.013,11.817,0)"><path d="M409 504C401 567 396 607 392 642C354 654 312 665 266 665C137 665 60 583 60 487C60 374 161 325 225 290C300 250 355 215 355 141C355 68 311 21 235 21C131 21 86 122 71 183L41 176C48 128 61 42 68 21C78 16 93 8 118 0C142 -7 175 -15 216 -15C349 -15 438 69 438 174C438 287 344 333 265 374C186 414 138 449 138 522C138 576 172 631 249 631C336 631 363 562 380 499L409 504Z" id="g121-81"></path></g><g transform="matrix(.013,0,0,-0.013,17.822,0)"><path d="M493 503C489 551 484 614 483 650H43V622C120 616 128 611 128 525V126C128 40 120 34 40 28V0H312V28C221 34 213 40 213 126V307H316C407 307 412 296 424 227H453V420H424C412 355 407 346 316 346H213V584C213 613 216 616 246 616H322C398 616 419 607 436 579C449 559 455 539 464 499L493 503Z" id="g121-68"></path></g><g transform="matrix(.0091,0,0,-0.0091,24.793,3.132)"><path d="M327 325C324 350 312 408 304 433C283 442 256 451 213 451C120 451 59 391 59 320C59 243 125 210 188 181C237 158 266 136 266 93C266 52 231 24 195 24C134 24 93 81 74 148L42 143C42 106 51 37 59 23C78 8 125 -12 177 -12C257 -12 345 35 345 127C345 198 292 234 216 264C171 283 131 305 131 348C131 387 156 416 195 416C243 416 277 378 297 317L327 325Z" id="g58-113"></path></g><g transform="matrix(.0091,0,0,-0.0091,28.178,3.132)"><path d="M244 0V30C178 35 170 41 170 107V710C136 697 72 680 18 675V647C83 642 89 639 89 572V107C89 43 80 35 16 30V0H244Z" id="g58-106"></path></g><g transform="matrix(.0091,0,0,-0.0091,30.544,3.132)"><path d="M262 451C169 451 38 375 38 210C38 98 121 -12 261 -12C360 -12 481 64 481 227C481 351 386 451 262 451ZM249 414C337 414 385 320 385 204C385 70 333 25 272 25C189 25 134 117 134 241C134 355 189 414 249 414Z" id="g58-109"></path></g><g transform="matrix(.0091,0,0,-0.0091,35.102,3.132)"><path d="M708 439H523V409C587 401 594 395 581 344C562 272 534 184 513 118H511C468 225 428 330 391 434H361C318 317 283 217 244 121H242C218 196 193 273 170 349C157 394 160 401 220 409V439H10V409C60 403 67 394 86 343C127 224 165 109 201 -10H233C273 101 314 199 353 299C393 195 432 99 475 -10H507C554 126 596 251 627 334C648 390 657 401 708 409V439Z" id="g58-117"></path></g></svg> for POPC at three temperatures. The solid lines represent the fitted model described in the text (see equation (<a href="https://static.hindawi.com/articles/jchem/volume-2017/3654237/figures/#EEq6">6</a>)). (b) Parallel (in-plane) displacement and perpendicular (off-plane) displacement versus temperature.</div>

Journal of Chemistry

fig7

Figure 7

Figure 7: Molecular Dynamics of POPC Phospholipid Bilayers through the Gel to Fluid Phase Transition: An Incoherent Quasi-Elastic Neutron Scattering Study 

Figure 7 | Molecular Dynamics of POPC Phospholipid Bilayers through the Gel to Fluid Phase Transition: An Incoherent Quasi-Elastic Neutron Scattering Study 