the Origins of Molecular
I n 19.3 the Iiorrnn rlrmistirc a n s aigncrl, \1011nt, ICvrrrst 1v:w rlimlwd, Q I I ~ ~Klimhrtlr II I : r n v n l : I \V:~tson nnrl Crirk cliscovmd the s t n ~ r t n r cof DS.\. 1 %thr ~ l!lfiO's 1)S.k h:~dhrromr t h r golrlrn molrrnle of tlir l~iorl~t-mists; ~ n i r t i c i s t s: ~ n drl~rnrists,1vl10 for y m w Imd f:~ilrtltn rst:~I~lish :r common g r o w d of onclrrstnnding, fo~lndit in I)S.\. 1 ' 1 1 ~ yv:~r l!).j:$ srrms, thrn. in mark :I t n n ~ i n gpoint !vl~rn mnlrrnl:~rl~iology c:mr of : ~ g r:IIICI tlw r s l m ~ ~ r n t igrnwt11 :~l of the sul~jrrt. hrg:~n. ' h i s hrrnic pirtnrr, t~owrvrr r n n v i n r i ~ ~ g , 1r:ivrr 11% in tlw d:~rk:IS In t h r n:~turrof thc conrrpt11:11 rrform whir11 lies lwl~indit. \Y:IS it ~ I I Pdiseovrry of Imv-p:iirinp in DX;\ whir11 :~ltrrrdtlw cnnrw of l~incl~rmi.stry,or wnirtl~ingrlsr? l'lw virw to Iw rspor~nclvcll ~ r wis thnt t h r trnnaition frnni t h r sm:tll-molrrnlr rl~cmistryof t.lw ninrtrrnth c n ~ t w yto t h r l:~rgr-molrr111rrl~rmislryof t h r I!UO's onw:~rcls,rrsolvinp :IS it did t Iw p:~r:~dox of rolloid:~lIICh:wior, rrprrwnts tlw i r : ~ l rrform. 'I'his hriug .;n, t h r is onr most mr:minpfnl drlinitinn nf # n n l r c ~ ~ lhiolngy :~r whir11 d:\trs t l ~ sul~jrrt r h:wk to ill(. limv Illis ronrrptn:~l r f r n I : I I If wr r:111 it thc d w c r i p t i n ~of~ form : ~ n d fnnrtion : ~ tthe m o l r c ~ ~ I :Irwl. ~ r ~ I I I Y I t h r snl>jrrt 11:~s h c w ~in r s i s t r t ~ r rfor ovrr 11hnrrclrrd yrars. I f \vr clvni:ind t11:1t snrh rtudirs must Ii:wc~providrd kno\vlrdpc of tlw tl~rrr-clinirr~sio~~:~l s l ~ : ~ pofr nrnlrrnlrs, then it is d e w th:~t littlr n i n r t w n t l ~r w t u n work WIS prrrisr rno11g11to qw~lify. I h t to t11r rstrnt tlmt trrhniqnrs more powrrfnl thnn tl1:11 of t l ~ tn~dition:~l r lipl~tmicrosropr 1vrrr in n ~ t l, ~ r s rrnrly s t ~ ~ d i rrrprrsrnt < tlw h r g i n n i ~ ~ of g s t h r snhjrrt whirl^ only rnmr into its own with t h r clisrovrry of dilTr:~ctionof S - r : ~ y sI)?. cnst:du rind t l ~ rinvrntion of t l ~ rlrrt r rnn mirrnsropr. This hrnncl d r l i n i t i o ~of~ t h r snhjrrf r o n t n ~ s t swith the mt~clin:rrrn\vrr nsr of t h r trrm hy t h r mirrnhinl : u ~ d virnl pI1ysinlogi4s. of w11nn1 Srymonr ( ' ~ I I ~ III:IS I s:~idin his .1rs1111I.rrtr~rrsth:lt they 11:wr nsrcl tlir lnhrl "to :~flirmt l ~ r i ri(1r11tity" n ~ t l ~th:~n r r to drlinr t11r sphrrr of thrir :rrtivitic*s. C;r:~ntcrl t11:lt thr trrm II:W romr illto usr for soriolngic:~l:IS wrll :IS for srirntifie rc:~snns. for 111r pilrpnrrs of this stndy wr will ~ : I S S ovrr tl~r n:~rrn!v drlinitirnr :tnd t r w r instr:ul t h r oripins of t h r s ~ h j r c :IS t morr 11m:idly r o ~ ~ c r i v w l .
pro:~rh11:1cl l u m f n ~ i to s r r :I wide are:\, hut 1111- mow :~nil)itio~~s :~imof r r d n r i n ~t h r ~ procrssrs r to moIrr111:w vil,r:~tio~~.; not only provrd niislmding l ~ n 1v:1. t s I H I ~ I to I~ f : i .\t t h r ..:~nir timr. I ~ o w v r r ,mon likr 1:ritsrhr wrrr s t ~ ~ d y i nrrll g i n ~ l ~ ~ s i nhyn sthe :lid of ~ m I : ~ r i m I light. 'I'lwsr .duclirs did lrntl to tlw disrovrry of tlw clct:rih of ultr:~.itn~rtorr.in s1:lrrlr pnrinr, re11 \v:11Is, nnd n r ~ ~ s rlilwrs. lc The Ultraslructvrish I n 18.58 t h r Swiss hnt:~nist,C:rrl Siigrli. 1vI1ois k t t r r known :IS 3Irndrl's evil st:w for f:tiIing to :~pprrci:~tr tlw worthy monk's thrnry of hrrrdity, :wsrrtrd t l ~rrysr t:lllinr nxtrirr of the l~oildii~p I~lorksor "molrrulr%," :IS hr c:~llrd thrm, of l v l ~ i r l11r ~ irr-lirvrd st:~rrhto lw romlmsrcl (we 12ip. 1). At tl1:11 tinw tlir eoncrpt of the
Figure I. Nb'gell'r pidvre of smmh micells in 18S8. showing wekm bemicclls, young s p h e r i d micellr, ond older anlorged m i 4 h which ore polyhedrd in mngcntid ssrtion MI ond elongated in lhs rodiol section (81. A Iresh l a y e r of micalh has formed ncor h e b o n a ol %orh a e n lhe
molecule \V:IS c o n f ~ ~ s nnnd l , it 1vnn not until the Knrlsrulw ('onferrncc of 18fi0 t11:rt i\vognclrnk 1,:tw won srrious considrr:~t.ion :ind t h r molrrulr Iwc:imr :III :~prrrcl entity v i t h t h r mr:~ning now :~ftnrhrclto it. S i i ~ r ltlam i hnd to chnnpr his tcmn molrrnlr to micrllr (:I littlc m ~ m h to ) show thnt hr I I : I ~ in nrinrl :a1 nssori:~tion of molrcr~lrs-111) to :IS many ns NKh3 of t l w n in rnrh mierllr, p i ~ r k n lin cryst:dIinr :irniy. X?iprli i ~ ~ t r n d n r two r d import:~nt c o ~ ~ c r p t x :(1) the cryst:illinr s t : ~ tof ( ~the suh-units of sn-c:~llrd n m o r p h o ~ ~ s sr~hst:rnrra,: I I ~(2) tlw ~rtstr~l:~tion of two lrvrls of Early Biophysics : c k i I m o l c r ~ ~ l:: ~ Ir I n ~ i r r l l ~ r :\t. . thc snmr timr IIC hrlcl t h r st:~rrlin~olrrulrto l ~ smnll r (formul:~ As rnrly ns the 1840's :I hnnd of hiophysirists rsistrcl in the prrwns of C':irl Imlwip, 11rrm:11111Vnn Helm('lrllln()m). IIis :wrrtion of cryst:~lli~~ity !v:w rollr:Igrc rh:d not rmployrcl t hr ~x~l:~rizing micrn'irq~r holtz, i h s t Rriirkr, nnd Ilmil ~ I IHois I ( r y n ~ o ~ ~ d o, w s i ~ ~hr in warch of anisntrnpy :lnd wna un:wnrr nf Ilncn von wl~oscprogrnm it 1v:w to rrdurr :dl hiolopirnl prncrssra 3lold's cvidrnrr of positive l~irrfringrnrr of stnrrh I X v t n i : n m r l ~ n ~ i r s Thry . wrrr m r c r s s f ~ ~in l gnrins, whirh :~ppr:~rrcl :lt the sxmr timr :IS his own shoving I t somr pl~y?;iolopic:~l prorcssrs olwy t h r 11:11)rron st:~rrhg n h * of 18%. In 18>!l SAprli folI:trvs of pl~ysirs.RIKI 11). the P I I of ~ t11r r r n t u n this n p
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lwrml of Chemical Education
lo\vrcl VOII llohl's rx~ml~lc., :IIIII from thrn nn hirrfringrnrr st.c~di~.s 11:1vr s r n w l widrly to givc i~~fnrm:It ion :iIm~tt h r p:~ckingof m o l r c ~ ~ lin r s 1)ioIogird stnwturrs I : I I I ~I o r i ~ ~ t : t i oofn i r I - I I ~ . Sligc4i's s l ~ ~ ~ l r:\ni11rn1111, nt, o l ~ t : ~ i rvi~lrncr ~ ~ r ~ l of 1111- rrys1:dlinity of c r l l ~ ~ l o in s r I!llti, f m r yr:~rsIrforr Srhcwrr's X-ray pirturr.; of mmir filrrs. ,\s r:~rly as I%%:% ;\rtln~rllc-yrr ~ ~ n t r~cPl : I I I I I ~ : I ~ ~ in I I I rhlorn111:1sts I~ 1111(1rr t I l r light mirmsrolw. l'hrsc~" ~ ~ I I I :wrrr I " r~di.;rovrrrd I I ~I k ~ ~ ~ t r r l i ginn c I~ :~ncl I!vn ycws I:llcr l;rry \\'yssling rrl~t:tinwl r v i l r ~ ~o rr I h y r r n l slnlrturr from hi.; hirrfri~~grnrr s t ~ ~ c of l y rhlornpl:~st.;. 111 I!KW II? ~ m s t ~ ~ l :I hr ~ I prrwnrr r~l of :~Itrrn:~tr 1:iyrrs of p r n t r i ~ ~ :u~cllipid: t l ~ w wrrr r irlcwtilircl ill niorr (lrt:iil frcrni s111di s w i g I r l r r t r ~n ~i i r r o ~ Ir 1 : l ' l ~ r: ~ t t : ~ r k on 1111% s t n w t l ~ r rof I)S.\ \v:w likr\visr ~ ~ r r f : ~ I>y rrd I~irrfringcmrrs t ~ d i r swl~irhrrvr:~lrd t h r r ~ i s t r n r rnf strnngly ~ml:~rizing groups whow p1:mrs w r r at right, :rnglw to t h r filwr :Isis : I I I I ~ i~:~rklmrw c h i n of t h r n~olrCIIIV. S-r:ty :~n:ilyrisI I .\stht~ry ~ :~ncl13141in 1WR rnnfirnird this lincling. This is the ~msitivrsidr to S!igrli's work. The 11rp:ltivr sirlr to his work rrntrrs on his clisniiss:~lof thv rnnrrpt of 1:rrgr niolrc~~lrs : u d his intrnrl~~rtion in thrir 11l:trrof m i r r h r :iggrrg:~trs,:I constnwt which provrcl i~~vnlu:~lrlr to t h r coll~~id rhrnlists, l ~ whicl~ t (lrl:rytvl t h r nerrpt:\nrr of t h ~m:~rmmolrrulr , cnncrpt .
t w y nf lifv Inv-:irnr :I p n ~ l h r nin the. colInicl:~lproprrtic-s of pmtnpl:~smill111 its ~Ivriv:~tivrs. . \ t l r n ~ p t s to 11ri11gII:IIII~:II high polynirrs into t h r fnhl nf tllr org:~nirchrn~istII:III il~clrnl11rc.n ni:~clrIn11 with11111s u c w s . I k c t u w frw ~mlynirrsdissolv~~ fr\v ro111d hr cryst:~lIizr~l.:IIIII for t1111sr like I~rninglol~in wl~irh~Iiwolvr~l :ind ~ryst:~llizwl tlwrr w:w no rrrI:iil~ty 111:it 1111.y fnrmrd l ~ o n ~ o g r n r orryrt:~ls. ~~s So IIIIIK :L* synthrsis of t h r sul,st:rt~rr I I ~:I known I~iorlirn~ir;~l I : ~ I : rrni:iinrd I i n ~ n s i l ~ l s~~spirions r, :IS to 1111. purity of the, rrystxls c m ~ t i n ~ ~tor din, voirrd I)?. t l i r Ihrl~cwii*ts. TIIII*l,:mil I:iwlw~, who II:III s y ~ ~ t h ~ ~ s i z r d :I sug:Ir ~Irriv:~tivv with n ~ o I r r ~ ~\vrigI~t l : ~ r .lWl in l!Il: ~ : Iof ~~~II~ The Aggregate Theory cov:tlrut :ud ionic l x ~ ~ ~ cend l * , Jol~:int~r.: I I~ic+'s tlicwry T h e principle of condrnsntion wherrhy s u r c r ~ ~ i v e l y of "p:~rti:~Iwlcury," whir11 II(> : d v x u r ~ di : ~lR!l!l to :LCcouut fnr thv w r y n w t i v r n:~turvof unr:~tur:ite~l nrInrwr orgrmic molecules :in. formed WI?; first put for10 wnt:iin :i r n d v i c l r : ~ g:n!ic romlmunds, could In* srcm ward hy ('hrvrrul for f:~tsin 1816 where it led to the of rrson:inrr. l%utiu l!W 1I:irrirs usc~lp:irti:tI x ~ l r u r y postulntion of comlmuuds with molecul:~r wrights no stnlcturr for n ~ h h r r . grcrlt(Lrthnn ROO, In11 with prnteins and csrlml~yclrntcs to prnlmw :nu :~ggn.p:~tc Cncertnintover the molcculc concept, cnmc nt. the :\ f i ~ rh r p r numlwr of I ~ u i l h g hlorks are involvrcl in snmc time :w clrtcrmined :~ttrmptswere k i n g madr to thc form:ition of high molreul:~rcomlnnlnds in, to quote study nntur:il lmlymrw hy the trchniques of t h e t e e n t h Hesq, ":i downright s h ~ r k i n gm:rnnrr." T h e $:\me century chrmiatry. I:mm 1!Ml o n w ~ r d sthe iden of principle n p p l i d to prntrins, he cleclnrcd, "would yield secondnry or pertinl vnlrncirs W:IS pushecl hy Hes-, chr~insof truly fnntnstic Irngths, thc cxistencr of which Iinrrcr, Hnrrirs, nnd Rrrgm:u~n,nlthough \Vcmer h:~d cnn he n ~ s u m r dw r y impml):iI)lr nccording to our i d e m " given u p I\ fundnmentnl distinctio~r \wt\vem~prim:wy W:IS sure m~ch long And in the e w e of ~mlys:~ccll;~rides he :~ncl sccondnry v:~lcncy in 1!l1:1. Clearly these hi* chnin structures "would couflict with the very c x c r p chemists w r e nnxious to keep the molcculc concept tionrd physical prnpcrtirs of crllulose." When he couwithin the scope of the techniques of the organic chcmsidercd the n ~ s with e which crllulosr cnn he mcthyl:\td nnd ncrtylntrd, ho\\, rrntlily glucose forms doul)lr s:~lts ist of t h s t perind nud to preserve the existing clnssilic:ltion of these insoluhle rrntur:~lnnd synthetic pol?with metal s:~lts,he concluded th:it the chcmic:d :\finit? mcrx RS ~ollnidswhosr s u p p o ~ r dn t y h d Iwhnvior is of the plucosr residues in the crllulose molcculc is not. due to their ngyrrp:rtc state. Some properties of polysnturntcvl. There is snmc rrsidunl nffinity left which * to \venk Imnds such :IS the hymers nrr of C O I I ~ S C due could :\ct hetween nrighlmring rcllulosc molrculrs to drogen lmud : ~ n d\vr mny conjecture t11:1t w m e t l h g form n pscudn-ginnt moleculr or : ~ g r e g : ~ t c .S o r did like n hydrngeu lmnd may h w e heen in the hnck of t.hc he hnve to look far for :b precede~it for violnting the minds of Rcss nncl I
