小样本量的旋光测量

旋光测量是一种常用的分析方法，用于评估合成的化合物以及从天然产物中分离和纯化的化合物。在大多数情况下，在合成过程中获得的材料和从天然产物纯化中获得的那些材料的量通常非常少。因此，必须能够使用最小的量来测量这些样品，这需要使用小体积的圆柱形样品池。本应用说明演示了使用仅1 mL的样本体积测量旋光度。Introduction P-2000 for Opti c al Rotat i o n M ea sureme n t Opt i ca l rotati on w ea s ur e m e nt is a c omm o n a naly tic al wet h o d use d for t he evaluat i on o f syn t h e s i z ed c ompounds an d compou nd s i so la t ed an d p u r i f i e d fro m nat u ra l pr o d uct s.I n most of cas e s ， t h e amo u nt of mat eri a l o bta i n ed d u ri n g synthesis an d t h ose o b tained f ro m na t u r a l p roduct pu ri fic a t i o n i s u s u all y v ery small. Th eref o re ， i t is ess e n ti al t o b e able to weasu re th e se s a m ple s us ing the swal le s t amou n ts w hich req u ires t he u se of sm all v o l u me c yl i nd r ic al c e lls . T hi s a p p l ic a ti o n no te d emo n strate s the m eas u r em ent of optic a l rotatio n u sin g a samp l e v o l u me o f on ly 1 mL. Table 1. C e ll s i z es and recommended ((minimum m)) s s ample v olume s Cell Diameter Cell path length： 100 mm Cell path length： 50mm 10 mm 9 mL 5mL 3.5mm 1.6 mL 1.4 mL(1mL) 2.5mm >1.4 mL (1mL) 一 The values in () are the minimum sample F ig .1 C ylin dr ica l Ce l l 2.5 mwD x 100mmL Features ·P-2000 Po l arime t er w i th s odium la m p and 589nm f il t e r ·P TC -262 P e lt i e r c ell hol de r fo r t e mpe r a ture c ontro ll e d m e asure m en t ·Minimum 1 mL sa m p l e vo lu m e (w hen u s ing c e ll s of 3.5 Mm D x 50 mm Lan d 2.5 mmDx100mm L ) Sample preparation 10 mg of p ira rub i c i n was a cc u r at e ly w eig h ed a n d a dd e d t o a 10 m L weasuring fl ask ， d i ss o lve d with ch lor o for m a n d t h en d i l ut e d t o 10 mL to t al v ol u me (at 20°C). Measurement conditions Instrument： P-2000 Polarimeter PTC-262 Peltier thermostatted cell holder Cells： Glass cells (size： 2.5 mm D x 100 mm L， 3. 5 mmD x 100 mm L) Light source/Wavelength： Sodium lamp / D589 line Measurement Temperature： 20°C N o t e： 。Te mpe ratu re sho u l d be rec o r de d prior t o weasur e m e nt as t h e pr o be may in te rfe re wit h t he light pat h . ●·M ake s u re t h at t h e r e are n o b ub bles in t he ce ll， esp e c i al ly n ear th e wind ow s . Bubb l es May c a u se inacc ur at e m easu r e m e n t. 。 if the re is suf fic ie n t availabl e s a mple a v a i l ab le，i t i s r ecomm e n ded t h at a c e ll of 10 m m D x100L mm i s us e d t o ob t ain more simple an d stable meas u reme n t resu l t s. Keyword s p irar ubic in， p o l a ri mete r， P-2000， o p t i c al rota ti on Results Measurement Results 2.5mmDx100 3.5mmL x 100 Description in JP([a]D20：+195 mm L glass cell mm L glass ce11 +215°(10 mg， 10mL，100 mm)) Optical +0.2066° +0.2021° 一 rotation Specific optical rotation(a) +206.6° +202.1° +195 +215° Conclusion Optical rotation measurement of pir a rubicin Amon g the phar m a ce utica l c ompounds desc ri b ed in the var i o u s pharma co poe i as su c h a s E P ， US P a n d BP， t here a re require me nt s f or o p t ic a l ro t at io n meas u r e ment o f small s a mp l e vo lum e s of v a l u able ma t eria l. On e such e x a mpl e is th e measu r emen t o f o p t i cal rotat i on of pi r ar u b ic in ([x ]D20：+195~ +215°(10 mg ， c h l oro f orm ， 10 ml ， 100 mm)) i ndicated in the J P 16th Editi on w a s meas ured w ith cel l s o f 2.5 mm D x 100 mm L cell a nd 3.5 mm D x100 w w L . Th e resu l t s hows t h a t even t he sw a llest a w o u nts of s a mp l e c an be e a si l y measu r ed . Featured Products： Di g ita l P o l a r i me t ers Disc r e t e s o dium 589 n m D -l ine P-2000 Na + Tung sten h alog e n l am p for a ppl ica tions in the vis i ble r e g i on P -2000 WI