- Cay che: Gi6ng Camellia sinnensis van shan TB14.
Hlnh 4b Phii' UV ella alginat dl!-ng bot theo li€u Xl!-
Ke't qU<1 v~ ph6 UY tren hlnh 4a va 4b nh~nthily r~ng ph6 elY cila alginat chie'u x~ 0 d~ng b(>t kha va d~ng dung dich, dien hlnh la dung dich 4% la gi6ng nhau, chi khac nhau v~ clfong dO, xuilt hien dinh moi Amox t~i 267nm voi cuong d(> tang theo li~u x~. Nguyen nhan co the la do qua trlnh chie'u x~ alginatt~o ra cae nhom carboxyl va carbonyl.
Mat khae theo gia tri m~t 0(> quang l,li 267nm ma oanh gia thl chie'u xa dung dieh alginat 4% t~i lieu 100kGy dat gia tri tlfdng oUdng voi ehie'u x~ alginatcl~ng b(>l kho l~i lieu 500kGy.
1.2. Phd In
Ke'l qua v€ ph6 lR cila alginal oUQc lrlnh bay lren hlnh 5 (xem ph~ I~c)cho lhily ph6 IR cila cac milu alginal chiEu x~ lrong khoang lieu x~ III0 - IOOkGy khong xuill hien dinh moi.
Ngoai ra nhom COO· cila alginal lhuong oUQc dung de so sanh lrong ph6 06 lR [8] va oUQc xem la khang lhay 06i lheo li€u X~. Khi so sanh li so' clfong dQ gii1a cae dinh C-O-C (l088cm 1) va COO' (l6IOcm·1)
nh~nlhily ly so' nay co xu huang giam d5n khi lieu x~ lang (Bang 12).
Bang 12: Ty so' clfong dQ lc.o.cllcoo- cila alginalWdung dich alginal4% lheo li€u x~
Dose, kGy lc.o.c / lcoo- :
o 20 50 100 1,9J 1,62 1,48 1,36
Tli ke't qua bang 13 cho lhily n6ng ,1(> cila lien ke'l C-O-C giam d5n (!leo li€u x~ va di€u nay chung lo r~ng khi chi€u x~ alginallhl qua lrlnh dl m~ch xay ra t~i lien ke't nay. Mat khac lrong cilu truc m~ch cila alginal c6 2 lo~i lien ke'l C-O-C, mQl0 trong m~ch vong va mQl la lien ke'l glucosit.
K€t qua v€ ph6 cQng huong Woien lit (Electron Spin Resonance - ESR) lren hlnh 6 (xcm ph~ I~c) cho lhffy qua lrlnh oal m~ch xay ra t~i
lien ke't C-O-C glucosit [IIJ. MaC khac Wenwei va c(>ng st/ (1992) [79] cang xac nh~n oi€u nay khi nghien cuu anh hlfong cila buc x~ gamma Co-60 oe'n qua lrlnh dl m~chchilosan. Cdche' cila qua lrlnh oUQc ma la tren hlnh 7.
COONa ~OHH H° ~OHoH OHH ° H OH H COONa COONa Bucxl.'----1.~ {)OdH OH + Y H H OH
Hlnh 7. Cd che' dt ml.'ch alginatb~nghac xa gamma Co-60. 1.3. Kh6i hiqng philn tu-Mn va Mw
Ke'l qua bang 13 va 14 cho tha'y kh6i IlI<jng philn ltl Mn va Mw cua alginal chie'u Xl.' giam ra'l nhanh lrong khoang li€u Xl.' lu O-IOOkGy d6i vdi milu alginal dl.'ng b9t kh6 va trong khoang li€u Xl.' W0-20kGy d6i vdi milu alginal dang dung dich 4%. Tuy nhien sau khoang li€u Xl.' n6i tren d6i vdi cii hai lnlong h<;Jp kh6i ItI<;Jng philn ltl Mn va Mw cua alginat chie'u Xl.' giam vdi muc (19 cham dlln.
E>i€u kha 19 lho a day la d9 da philn Lan hay con gqi la d9 phan b6 kh6i IU<;Jng philn ltl (Mw/Mn) lrong cii hai tn(ong h<;Jp chie'u Xl.' dl.'ng b9t va dung dich d€u giam dlln khi lang li€u xl.'. E>i€u nay c6 khac vdi ke't qua nhan dU<;Jc cua m9t s6lac gia khi Stl dung enzym hOac la sieu am M dl ml.'ch polysacaril (Chabrecek va c9ng st!, 1991) [38]. St! khac bi~tla a chii d9 da philn tan tang dlln Mn m9t mac d9 nha'l dinh nao d6 sau d6 giam xu6ng thea melc U9 suy giam cua kh6i IU'<jng philn ttL Tuy nhien nhung ke't qua nay Il.'i g6ng nhau la khi kh6i ItI<;Jng philn ltl dng nhc thl u9 ua philn Lan cang be.
Qua d6 cho tha'y uay chinh la m9t uu ui&m cua ky thuat buc Xl.' Stl dung tia gamma Co-60 M che' ll.'o OA c6 u9 udn philn tan Cao (u9 da phan Lan nhc).
- Ke't qua v€ u9 nhdt cua dung dich alginat thea li€u Xl.' dIng cho tha'y melc u9 giam ra't nhanh a khoang Jj€u Xl.' lha'p (BangI5). Tu khoang li€u IOn hdn 50kGy uQ nhdt cua dung dich alginat 1% tu alginal chie'u Xl.' dl.'ng b9t kh6 c6 gia lri nhO hdn 12Cps. Ke'l qua nay ding kha phil h<;Jp vdi ke'l qua cua lac gia Kume va Takehisa (1983) [55] khi nghi~n cuu anh huang cua buc Xl.' gamma ue'n alginal va caraghinin. Ta'n Man va c9ng st!(1999) [18J ding nhan dll<;Jc ke't qua llldng tt! khi nghien cuu anh huang cua buc xl.' gamma Co-60 de'n u9 nhdt dung dich cua m9t s6
polyme tl/ nhien. Tinh eha't nay eua alginat ehie'u x~ ding ra't huu ich trong nhi€u trtfong h<;1p din n6ng 09alginat eao rna 09 nhdt tha'p.
Bang 13. Mn va Mw eua alginat ehie'u x~ d~ng b9t kho
Dose,kGy RT,min Mn Mw MwlMn 0 7,45 418.594 536.431 1,28 10 7,85 177.607 219.740 1,24 30 8,15 95.024 I14.588 1,21 50 8,43 51.713 60.822 1,18 100 8,67 31.434 36.225 1,15 200 8,84 21.756 24.695 1,14 300 9,02 14.740 16.467 1,12 400 9,13 11.665 12.906 I, II 500 9,22 9.756 10.716 I, I0
Bang 14. Mn va Mw eua alginat ehie'u x~ d~ng dung dieh 4%
Dose, kGy RT,min Mn Mw Mw/Mn
0 7,45 418.594 536.431 J,28
20 8,83 22.366 25.416 1,14
50 9,20 10.180 11.20J 1,10
100 9,42 6.375 6.881 1,08
Bang 15.89 nhdt dung dieh alginat 1% pha tt( b9t alginat ehie'u x~
Dose, kGy 0 5 10 £>9 nhdt, Cps: 248 97 43 20 21 30 17 40 50 J4 12
1.4.Hi~usua't phan huy m<lch bucX<I Gd
Bang 16. Hi~u sua't phan huy m~ch buc x~ Gd cua dung dich alginat thea n6ng oQ
N6ng oQ dung dich, % 2 4 10 100(d~ngbQt)
Gd, s6 odn vi m;\t xfeh
24,37 13,59 5,47 1,63
monome bi oal/l00eY
Ke't qua bang 16 ou'<;Jc bi~u di€n len 06 thi hlnh 6.
Gd= 34 33Co., 684 ~ -0 0 30 ~ ..c:: u 25 Ol· E >- 20 ."..c:: 15 " 'Ol ..c:: 10 0. ~ \Ol 5 " '" " a 'O.l- :r: a 20 40 60 80 100
N6ng 0(\ dung dich alginat, %
Hlnh 8. Tu'dng quan giua n6ng 0(\ dung dich va hi~u
sutt phan huy m~chbuc x~ Clla alginal.
Tu ke't qua bi~u di€n tren 06 thi hlnh 8 xac oinh ou'<;Jc m6i tu'dng quan giua hi~u sutt phan huy m~chbac x~ Gd 06i v(ji alginat 0cac n6ng 0(\ C (%) khac nhau thea phu'dng tdnh nhu'sau:
Gd =34,33C·O,684 (14)
Phtfdng trlnh nh~n ou'<;Jc rtt huu feh o~ ap dyng tmng cac qua tflnh nghien che't~ooligoalginat b~ng ky thu~tbuc x~ tu alginat noi rieng va
xae diM dti<;le khi nghien euu dt m~eh cae polyme llj nhien (ehitosan, earaghinin, pectin, ..) b~ng ky thu~tbuex~.
Tli' phtidng trlnh (14) eho tha'y khi n6ng <19 eua alginat trong dung dieh ding eao thl hieu sua't philn huy m~eh bue x~ ding tha'p. £)i~u dang ehu yo dily Iii n€u ehi€u x~ d~ng dung dieh hieu qua dt m~eh d~teao hdn so vdi trtiong h<;lp ehi€u x~ d~ng b9t, nguyen nhiln Iii do e6 "f d6ng g6p eua hieu ung bue x~gian ti€p tli' dung moi ntide.
Ta e6 th€ Ia'y vi dl! n€u ehi€u x~ d~ngb9l kho vii dung dieh 4% thl hieu sua't philn huy m~ehbue x~ Gd (tinh thea Mv) eua alginat ttidng ung Iii 13,59 vii 1,63. K€tqUit nay cho tha'y n6u chi6u x~ d~ngdung dich 4% hieu qua dt m~eh d~t eao hdn so vdi trtiong h<;lp ehi€u x~ d~ng bot khoang 8,3 I~n (13,59/1 ,63). K€t qua nily kha phii h<;lp vdi k€t qua nh~n
dti<;le ttlphlS UV cua chung.
M~e khac ttl k€t qua bang 13, bang 14 vii d6 thi hJnh 9 eho tha'y n€u tinh thea Mn thl hieu sua'l philn huy m~eh bue x~ Gd eua alginat trong dung djeh 4% Iii 1,84 vii d~ng bot Iii 15,86. Hieu qua dt m~eh
trang trtiong h<;lp nily eGng d~t khoang 8,6 I~n (15,86/1,84). K€t qua nily eGng kha phii h<;lp vdi k€t qua linh thea Mv n6i Iren.
160
o Alginat
'"' 0 120 • Dung dich alginat 4%
~" " 8 " 80 ;§ ~ Gd= l.R4 " 40 ;§ ~ ~ 0 a 100 200 300 400 500 Li~u x~. kGy
Hlnh 9. SIj phI! thuge (1/Mn - lIMnO) eua cae milu alginat thea Ii~u x~.
Tuy nhien n€u ehi€u x~ alginat d~ng b9t kho hieu sua't ha'p thl! nang lti<;lng bue x~ eua alginat se IOn hdn d~ng dung dieh. CGng dn phai ehu yr~ng ehi€u x~ alginald~ngb9t kho Ii~u cao e6 th€ diln tdi pha
huy diu truc yang glucosit cua polysacarit. VI vh vi~c il/a chqn ky
thu~tchitu X\I vii litSu X\I thleh h<;lp M cht t\lO OA noi chung Iii ra't quan
trqng trong nhitSu trl10ng h<;lp nhiim nh~n dt(<;lc OAco kh6i II1<;lng ~han ttl' vii st/ phan b6 kh6i Jt(<;lng phan ttl' mong mu6n. T6t nha't Iii nen ktt h<;lp cii hai c,\ch chitu X\I, tn(dc tien Iii chitu X\I alginat d\lng bot kho vdi I litSu X\I thleh h<;lp sau pha thiinh dung dich dn6ng dO nha't dinh, chitu X\I
dung dich noi tren 0 litSu X\I din thitt d~ thu nh~n dt(<;lc OA co trqng II1<;lng phan ttl' nhl1 mong mu6n.
Tren cd so nhC1ng dC1 li~u nh~n dt(<;lc chung toi dtS nghi qui trlnh chitu X\I dung dich alginalM cht t\loOA co kh6i II1<;lng phan tli Mv nlu( mong mu6n Iii nht( sau:
- Trl1dc tien din xac dinh kh6i II1<;lng phan tli Mvo cua alginat din chitu X\I thea pht(dng trlnh (I):
logT] =logk +alogMv
- T\lo dung dich alginat thea mot nang do nha't dinh C (%). Tli do xac djnh hi~u sua't phan huy m\lch b((c X\I Gd cua dung djch alginat t\lO ul1<;Jc thea phl1dng trlnh (14):
Gd =34,33C·O,684
- Tli Gd tfnh dtr<;lc, co th~ xac dinh dtr<;lc litSu chitu X\I din thitt d6i vdi dung dich alginat noi tren thea phl1dng trlnh (2b) M co dl1<;lc dung dich OAco trqng II1<;lng phan tli Mv nhl1 mong mu6n nhl1 sau:
Mvo
Mv= - - - - Mvo x Gd X D(kGy) x1,036x10.7+1
(J 5)
Milc khac tli (J4) vii (J 5) ta co phl1dng trlng t<lng quat nhl1 sau:
Mvo Mv=