Absorption spectrum of methylene blue, in terms of the molar extinction coefficient (base 10 logarithm). In this dataset a peak absorbance of 1.7 (i.e. 98% of transmitted light absorbed) was observed with 665 nm light passing through 1 cm of 10 micromolar methylene blue solution.
English: This work relies on two data sources which, in my opinion, do not rise to the level of copyrightable material. The spectrum is copied from File:Rendered Spectrum.png by User:Spigget; hopefully a spectrum is immune from such concerns. The absorption spectrum is taken from an online website of the Oregon Medical Laser Center at [1], which provides a tabulated set of absorbance measurements for a 10 micromolar solution of methylene blue (path length 1 cm) made by Scott Prahl. [2] Multiplication of these calculated extinction coefficients (base 10 logarithm) by 0.00001 and 2.303 yields original OD data going up to 1.7 at peak absorption, which should be safely in range of the instrument, an unspecified HP spectrophotometer. The chart was made by me using GIMP from the original dataset as follows. (Because w:database copyright does not apply in the United States, and so far as I know is not recognized by Commons policy either, I feel free to copy and use this data:) 200 12177 202 11446 204 10687 206 9865 208 9288 210 8810 212 8305 214 7924 216 7698 218 7376 220 7181 222 7114 224 7138 226 7341 228 7684 230 8022 232 8478 234 9146 236 10098 238 11363 240 12888 242 14478 244 15907 246 16885 248 16898 250 15787 252 14101 254 12457 256 11269 258 10573 260 10291 262 10355 264 10811 266 11662 268 12801 270 14127 272 15498 274 16960 276 18695 278 20827 280 23248 282 25937 284 28775 286 31752 288 34813 290 37552 292 39064 294 38802 296 36815 298 33466 300 29334 302 25069 304 21005 306 17413 308 14496 310 12299 312 10809 314 9883 316 9290 318 8830 320 8508 322 8255 324 8046 326 7875 328 7639 330 7204 332 6607 334 5850 336 5031 338 4262 340 3621 342 3058 344 2641 346 2336 348 2081 350 1886 352 1752 354 1590 356 1456 358 1346 360 1263 362 1187 364 1210 366 1128 368 1065 370 1067 372 1070 374 1071 376 1091 378 1117 380 1099 382 1141 384 1155 386 1177 388 1248 390 1257 392 1294 394 1283 396 1271 398 1248 400 1143 402 1085 404 990 406 899 408 777 410 693 412 687 414 616 416 575 418 543 420 598 422 629 424 565 426 589 428 662 430 711 432 652 434 769 436 783 438 861 440 900 442 943 444 1010 446 1041 448 1090 450 1169 452 1253 454 1303 456 1405 458 1556 460 1500 462 1637 464 1791 466 1735 468 1854 470 1825 472 2037 474 2022 476 2173 478 2254 480 2324 482 2429 484 2631 486 3055 488 2548 490 2773 492 2744 494 2730 496 2911 498 2902 500 2847 502 2927 504 2858 506 2889 508 2911 510 2919 512 2892 514 2916 516 2901 518 2977 520 2965 522 2998 524 3142 526 3319 528 3319 530 3461 532 3677 534 3832 536 3951 538 4344 540 4468 542 4833 544 5093 546 5409 548 5843 550 6189 552 6720 554 7094 556 7613 558 8080 560 8724 562 9381 564 10172 566 10892 568 11499 570 11981 572 12527 574 13318 576 14130 578 14954 580 16093 582 16927 584 18402 586 19208 588 20767 590 21983 592 23962 594 25365 596 26811 598 28807 600 30580 602 32239 604 33577 606 35201 608 36035 610 37418 612 38121 614 38626 616 38847 618 39148 620 39384 622 39694 624 39847 626 40321 628 40968 630 41725 632 42960 634 44176 636 46129 638 47803 640 49754 642 51895 644 54622 646 57263 648 60272 650 62654 652 66008 654 68935 656 73230 658 70273 660 71547 662 73004 664 74028 666 74014 668 73044 670 71089 672 67725 674 63368 676 57423 678 50928 680 44792 682 38591 684 31941 686 27209 688 22710 690 18448 692 14973 694 12227 696 9865 698 7947 700 6511 702 5331 704 4303 706 3670 708 2866 710 2406 712 2103 714 1750 716 1389 718 1297 720 1028 722 926 724 948 726 868 728 620 730 702 732 526 734 607 736 519 738 294 740 432 742 233 744 298 746 365 748 433 750 394 752 217 754 391 756 296 758 331 760 154 762 73 764 278 766 -2 768 246 770 253 772 -50 774 5 776 -2 778 221 780 311 782 63 784 -23 786 -6 788 156 790 93 792 40 794 223 796 -73 798 50 800 121