Three who pioneered in chromatography - ACS Publications

When interest awakened in the 1930's for the isolation of mixtures of natural plant pigments, workers natu- rally sought the publications of Michael T...
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5. V. Heiner Spolding College Louisville, Kentucky

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Three Who Pioneered in Chromatography

T h c history of chromatography, when i t is writ,ten, will st,art with the vast amount of work donc in this field before t,he dawn of the 20th century. When int,ercst awakencd in the 1930's for the isolation of mixtures of natural pplnt pigmcnts, morliers naturally sought the publications of Alichael Tswett (1-S), a Russian hotanist, who had worked in t,his idcntical field. Rut hefore him many carly scientists of repute had studied thc separation of colored mixtures and published their results in the leading English, German, French, and Russian journals of the day. Among these there are three who st,and out as original thinkers on thc subject,. Friedlieb Ferdinand Runge (1794-1867) (4, 5 ) , professor in Brcslau and Berlin, director of the chemical works a t Omnienburg, author of several textbooks on chemistry, pioncered in the use of unglazed papcr arid pieces of cloth for spot,-tcsting of dye mixtures and plant ext,racts. By adding drops of colored liquids to printing or blotting papers hc showed how t,he paper split t,hc colorcd mixturc into its components by forming a dnrli colored center surroui~dcdby a less colored circle. Hc attributed this separatior~to the capillarity of the pnper and to the spccific character of the liquid. H e expcrimentcd, likewise, with comhinations of salts and logwood solutions and published thc results in his Volumc 111, "I"arhcnchcmic" ( 6 ) . Rungc's so-callcd spontn~leously grown pictures which he called his chemic;rl coat of arms can be seen in his Rlusterbildcr. A continuanre of the latter puhlishcd in 1855 (see Fig. 1 for Tit,le l'nge) (7) contains a t least 120 of thcsc pictures, which according to Bcrthold Anft (8) still show exccllcnt color qualit,y. Only two copies of t,his book are thought to he extant,, one in hlunich, Germany, and one in thc United St:~tcs,privately owned. These pretty pictures havc been said to be morc for the artist than for the scientist, hut it c:tmrot be denied that they are ihc forcrunncrs of the modern circular cliromatograms (scc Fig. 2). About :r. decade later, Christian Schonbein (17991SBS) (0) a ~~rofcssor of chcmistrv in Raslc, stimulated a s t u d k i 'of 'his, I'ricdrich Gop~clsrocdcr' (183-1919), t,o hcgin a lifc work on papcr strip zuialysis of liquids (10, 11). A Table of Contents of a monograph by the lattcr shows that thc analysis with the strips included dyes, hydrocarbo~rs, alcohols, milk, beer, colloids, drinliing and m i ~ ~ c r awaters, l and plant and animal pigmcnts. There are many illustrations showing cabincts madc by the author with moisture and temperaturc cont,rol that are very much lilic the ones we huild Tnken from 1Iaol.s of Chl.omat.ogrnphy, a paper pl.esented lo t h e 11ixlot.y of Chemirt1.y Symposium, ACS meeting, Miami Beach, Flol.ida, April, lM7.

today. The picturcs of colored bmds on paper strips obt~nincclfrom t,he extracts of nntural products arc very well defined. In onc of the illustr:ltions i u this monograph tllc scparation of n mixturc of dyes mid indicators arc draw1 in dctail. A fcw of these strips have bcen sclcctcd (see Fig. 3) to show the careful scpnration of each component. Both Schonbei~~ nr~d Goppclsrocdcr, espccinlly the latter, have heen ncccptcd as origi~mtorsof the method of capiII:~ry:tnalysis. Tovards the turn of the century, Lester Reed of England in 199.7 madc sevcrnl studies 011 the separation of salts in solution by "selective adsorption in bihulous paper" (12). Hc acl~nomledgesthat he had completed quite a few of his experiments in igr~oranceof the work of Schonbeiri and Goppelsroeder. The main part of

Figure 1 . Title page of "Der B i l d ~ n g r l r i e b der Stoffe. Indiana university.

Courtesy of

Volume 46, Number 5, May 1969

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I One of the pictures from "Der Bildungstrieb der Stoffe" (Drawing from Notvrwisrenschaften (711. In t h e original the innermost rpot is brown ID), followed by a brighter area that is bordered in brown (CI. The other border splits into (81 o d a r k blue area and IAI o lighter blue scallop. T h e original rpot consisted of a mixture of AlClr, KsF4CNlr. and CuSOn.

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Figure 2.

Figure 3. Separation on p a p e r rtripr of colors from o mixture of dyes and indicators. Time a n d height of rise ore marked.

forgotten, have left us a heritage that serves to point to the fact that the beginnings of chromatography started about 100 years before the 1930's.

his studies dealt with the separatiou of colored salts and suhscqucnt chemical testiug as a possible clue to thcir idcutificatiou. To Reed also may be attributed :I "first." He says: "With regard t,o the employment of porous mcdin other thau filter paper, I have obt:iiucd satisfactory results, both with the mixture of potnssic chromt~tc:u~deosiu, and with that of ferric chloridc a i d copper sulphate, by using tubes containing p o w l r r d 1r:toliu lightly rammed down, upon the top of which thc n~lutioiimas placcd and allowed to su:!l< do~v~~~v\.ards. I had hopcd that this method of s r p r : t i ~ n ,or somt: modification of it, might have p r ~ v c d:~vnil;lblcfor the separnt,iou of alkaloids from org:rllic mattcrs of diffcrclit nnt,urc, with a view to their suhscquclit idcntificatiou, but havc 11ithert.o been vcry ~):irtiallysuccessful iu this direction." I?. Feigle (IS) says: ". . . i t sccms uot to be lmomu that L. Ilrcd, thirtecu years hcforc Tsmett, discovered that it is possil~lc to scp:~r:~tccrrtaiu inorganic aud organic s:dts (:~llr:~loids) by columu adsorption (on kaolin)." l'hcsc r i g i : I iuvcstigntors and many more like thrni, ~vhosc\vorli has now been overloolrcd or entirely

Literature Cited

T S W ~ M., T , Rev. deulseh, bol. Ces. XXIV, 316 (1906). TSWETT, M., op. cil., 384, (1906). TSWIITT, M., op. eil., XXV, 71-74 (1907). I~UNGII, F. F., Farbcnchemie, I and 11, 1834, 1843. (5) RUNGI:, F. F., Annalen der Physik und Chemie, XVII, 31,

(1) (2) (3) (4)

65 (1834): XVIII, 32, 78 (1934). (6) I~UNOI:, F. F., Fadxnchemie, 111, 1850. (7) WML, N.,nno WILLLIMS, T. I. Die Nalurwis~ensehajtm,14, 1-7 (1953). (8) ANFT, BI.:ILTHOLU, "Friedlieb Ferdinand Ilunge, A Forgotleu Chemist of the Nineteenth Cenlury," Trans. by OIISPI:I