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CH TO VT LIU NANO VNG CHITOSAN NH HNG NG DNG

TRONG DC PHM

Hunh Th Cm Quyn, Nguyn Th Phng Phong

Trng i Hc Lc Hng

TM TT

Trong bi bo ny, ht nano vng chitosan c iu ch bng phng php kh

ha hc vi tin cht HAuCl4, cht kh vitamin C trong mi trng chitosan. Cc yu t

nh hng n kch thc ht nano vng chitosan: thi gian, t l nHAuCl4/nvitamin C,

pH, nhit phn ng c kho st. c tnh ha l ca ht nano vng chitosan

c nh gi thng qua cc k thut phn tch ha l khc nhau nh: UV-Vis, XRD, FE-

SEM v TEM. Dung dch nano vng chitosan c ng dng trong sn phm chm sc

c nhn.

1. M U

Vng (Au) l nguyn t kim loi chuyn tip, khng c, c kh nng tng thch

sinh hc v c xem l tr nht trong tt c cc kim loi. Th nhng khi tn ti kch

thc nano, cc ht nano vng xut hin nhiu hot tnh khc bit so vi trng thi vt liu

khi nh: c kh nng xc tc cc phn ng sinh ha, thay i bc sng hp th theo kch

thc ca ht, c kh nng gn kt vi cc phn t sinh hc.

Hin nay, c rt nhiu phng php ch to ht nano vng chitosan, trong

phng php tng hp xanh c quan tm hn c do c tnh khng c hi n sc khe

con ngi v thn thin vi mi trng. Trong bi bo ny ht nano vng chitosan c

ch to bng phng php tng hp xanh vi tin cht HAuCl4, cht kh vitamin C, cht

bo v chitosan. c tnh ha l ca ht nano vng chitosan c nh gi thng qua

cc k thut phn tch ha l khc nhau nh: UV-Vis, XRD v TEM. Dung dch nano vng

chitosan c phi vo kem tr bnh nm da, tn nhang.

2. THC NGHIM

2.1. Ha cht

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HAuCl4.3H2O (Merck, 99,0%), (C12H24N2O9)n (Sigma-Aldrich, DD 75%), NaOH

(Trung Quc, 96,0%), CH3COOH (Trung Quc, 99,5%), Vitamin C (Trung Quc, 99,7%),

H2O (Merck, 99,9%).

2.2. Thit b

My khuy t IKA RET control-visc, c (Phng Ha l ng dng, H KHTN,

Tp. HCM); My o pH IQ Scientific Instruments (B mn Ha phn tch, H KHTN, Tp.

HCM); My quang ph UV-Vis-NIR-V670, JASCO, Nht (Phng Ha L ng Dng, H

KHTN, Tp. HCM); My TEM, JEM-1400, Nht (Phng Th nghim trng im quc gia

v Vt liu Polyme v Composit, H Bch Khoa, Tp. HCM); My o ph FT-IR

BRUKER EQUINOX 55, c (Phng Th Nghim Trung Tm, H KHTN, Tp. H Ch

Minh); My FE-SEM JSM 7401F, Nht (Phng th nghim cng ngh nano, i Hc Quc

Gia Thnh Ph H Ch Minh).

2.3. Phng php nghin cu

Cn 0,25g chitosan cho vo becher cha 50 ml dung dch acid acetic 1% khuy nhit

phng n khi tan hon ton, khuy lin tc khong 2 gi, chnh gi tr pH ca dung dch

chitosan bng NaOH 1M. Kho st kh nng hnh thnh ht vi cht tr kh vitamin C

bng cch thay i t l nHAuCl4/ nvitaminC. Kho st hnh dng v kch thc cc ht

nano vng trong dung dch keo bng cc cng c phn tch nh o quang ph UV-Vis ca

cc mu, chp nh TEM.

(a) (b)

Hnh 1: (a) Mu cha dung dch chitosan vitamin C - HAuCl4, (b) Mu nano vng chitosan.

3. KT QU V THO LUN

3.1.Kt qu phn tch nguyn liu chitosan ban u

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Cc kt qu phn tch chitosan c trnh by trong hnh 2.a (ph FT IR), hnh v

hnh 2.b (nh FE SEM).

Hnh 2: Cc kt qu phn tch ha l ca nguyn liu chitosan ban u.

Hnh 2.a l kt qu ph FT IR ca chitosan, vi cc nh hp thu nh sau:

3417,04 cm-1

tng ng vi dao ng ca nhm -NH2 v -OH ca chitosan, nh hp thu

1657,99 cm-1

tng ng vi dao ng ca nhm CONH2, nh hp thu 1598,68 cm-1

tng

ng vi dao ng ca nhm -NH2. nh hp thu 1078,43 cm-1

tng ng vi dao ng ca

nhm C-O-C.

Kt qu FE SEM (hnh 2.b) cho thy hnh dng chitosan ban u l tng lp

polymer ging nh hnh vy c.

Kt qu GPC cho thy: phn t lng trung bnh s: 162kDa, phn t lng trung

bnh khi: 497kDa, phn t lng trung bnh nht: 497kDa, ch s a phn tn: 3,07 ; DI >

2.

3.2. Kt qu phn tch UV- Vis ca dung dch nano vng chitosan

Cc kt qu phn tch UV Vis ca dung dch nao vng chitosan c trnh by

trong cc hnh 3a, 3b, 3c, 3d v cc bng 1, 2, 3, 4

(a) FT IR (b) FE SEM

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Hnh 3: (a) Ph UV Vis cc mu nano vng chitosan kho st phn ng hon ton nhit 80oC t 60 pht 300 pht, ti pH = 4,5.

(b) Ph UV Vis cc mu nano vng chitosan nhit 80oC c t l nHAuCl4/nvitamin C thay i t 1:5 11:5 ti pH = 4,5.

(c) Ph UV Vis cc mu nano vng chitosan nhit 80oC pH thay i t

4,0 5,0. (d) Ph UV Vis cc mu nano vng chitosan pH = 5,0 nhit thay i t

30oC 90oC.

Bng 1: D liu UV Vis ca cc mu dung dch nano vng chitosan nhit 80oC, pH = 4,5 thi gian thay i t 60 pht 300 pht,.

Th tch acid acetic1% (ml)

Nng cht kh(M)

Chitosan

(g)

t(pht) Abs Peak

(nm)

Mu

50 10-3

0,25 60 0,150 518 1t

50 10-3

0,25 120 0,158 519 2t

50 10-3

0,25 180 0,190 520 3t

50 10-3

0,25 240 0,237 521 4t

50 10-3

0,25 300 0,208 521 5t

(c) (d)

(a) (b)

(c) (d)

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Kt qu UV-Vis hnh 3(a) v bng 1 ca cc mu dung dch nano vng cho thy

khi tng thi gian t 60 300 pht th hp thu tng. hp thu ln nht tng chm

mu 60 pht, 120 pht, 180 pht. Tip tc tng thi gian 240 pht th hp thu tng

nhanh t 0,19(180 pht) n 0,23(240 pht), iu ny chng t ht nano vng to ra trong

dung dch kh nhiu, hnh dng mi c tnh i xng cao. Khi tip tc tng thi gian ln

300 pht th hp thu bt u gim t 0,237 (240 pht) xung 0,208 (300 pht). Nguyn

nhn l do khi tng thi gian qu mc gii hn ca phn ng, cc ht nano sau khi hnh

thnh, chuyn ng va chm to thnh ht kch thc ln hn lm gim s lng ht

kch thc namo nn hp thu gim. Vy da vo kt qu UV-Vis, vi t l

nHAuCl4:nvitaminC = 6:5, nhit 800C, pH = 4,5, thi gian thch hp tng hp dung

dch nano vng chitosan l 240 pht.

Bng 2: D liu UV Vis ca cc mu dung dch nano vng chitosan nhit 80oC

vi t l nHAuCl4/nvitamin C thay i t 1:5 n 1:11.

Th tch acid acetic

1% (ml)

Nng cht kh

(M)

Chitosan (g) nHAuCl4/

nvitaminC

Abs Peak(nm) Mu

50 10-3

0,25 1:5 0,067 518 1n

50 10-3

0,25 2:5 0,098 518 2n

50 10-3

0,25 3:5 0,108 518 3n

50 10-3

0,25 4:5 0,131 518 4n

50 10-3

0,25 5:5 0,216 518 5n

50 10-3 0,25 6:5 0,251 522 6n

50 10-3

0,25 7:7 0,268 522 7n

50 10-3

0,25 8:5 0,356 522 8n

50 10-3

0,25 9:5 0,463 522 9n

50 10-3

0,25 10:5 0,687 522 10n

50 10-3

0,25 11:5 0,486 523 11n

Kt qu UV-Vis hnh 3 v (b) bng 2,trnh by cc mu dung dch keo nano vng

khi thay i t l nHAuCl4:nvitaminC (t 1:5 n 11:5), (gi nguyn th tch acid ascorbic,

thay i HAuCl4). Trong khong t l nHAuCl4:nvitaminC t 1:5 n 10:5, nhn thy

hp thu quang tng dn 0,067 n 0,687 chng t s gia tng s lng cc ht nano vng

to thnh trong dung dch v c bo v bi cht bo v chitosan. Tuy nhin, khi tng t

l nHAuCl4:nvitaminC ln 11:5 th hp thu bt u gim 0,687 xung 0,067, lc ny do

HAuCl4 tng, cht bo v khng bo v ht nano vng to thnh nn cc ht nano kt

t li vi nhau t kch thc ln, s lng ht nano vng to ra t hn nn hp thu

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gim. Qua th nghim kho st cc t l nHAuCl4: nvitaminC th t l 10:5 l t l tt nht

ch to ht nano vng ti nhit 80oC.

Bng 3: D liu UV Vis ca cc mu nano vng chitosan c ch to nhit 80

oC, pH thay i t 4,0 5,0.

pH Th tch dung mi acid

acetic 1%(ml)

Nng cht

kh (M)

Chitosan

(g)

Abs Peak

(nm)

Mu

4,0 50 10-3

0,25 0,660 520 1p

4,5 50 10-3

0,25 0,687 522 2p

5,0 50 10-3

0,25 0,903 524 3p

Da vo ph UV-Vis hnh 3(c) v bng 3, ta thy khi pH tng th hp thu tng

do ht nano vng c to ra nhiu. Vi pH = 4,0 ph UV Vis c bc sng 520nm

vi cng hp thu 0,660; ti pH = 4,5 ph UV Vis c bc sng 522nm vi

cng hp thu 0,687; ti pH = 5,0 ph UV Vis c bc sng 524nm v cng

hp thu 0,903. Kt qu UV- Vis cho thy c s chuyn dch khi tng pH dung dch

chitosan. C th gii thch pH = 5,0 kh thch hp v ti pH ny chitosan tan tt trong

acid acetic 1%, ht nano to ra nhiu, c th ni chitosan lm tt nhim v l cht bo v.

Nu tip tc tng pH dung dch chitosan ln hn pH = 5 th chitosan khng tan, vn cc

li, lm gim kh nng bo v ca chitosan. Vy pH thch hp phn ng ch to nano

vng chitosan l pH = 5.

Bng 4: D liu UV- Vis ca cc mu nano vng chitosan ti pH = 5,0, nhit thay i t 30oC 90oC.

toC Th tch acid

acetic1%(ml)

Nng cht kh (M)

Th tch cht kh (ml)

Chitosan

(g)

Abs Peak

(nm)

Mu

30 50 10-3

5 0,25 0,497 524 1n

40 50 10-3

5 0,25 0,526 524 2n

50 50 10-3

5 0,25 0,568 524 3n

60 50 10-3

5 0,25 0,593 524 4n

70 50 10-3

5 0,25 0,618 525 5n

80 50 10-3

5 0,25 0,903 524 6n

80 50 10-3

5 0,25 0,622 527 7n

Kt qu UV-Vis hnh 3(d) v bng 4, cc mu dung dch nano vng cho thy khi

tng nhit t 30-90oC th hp thu tng r. hp thu tng chm cc mu t 30

70oC. Tip tc tng nhit ln 80oC th hp thu tng nhanh t 0,618 (70oC) n 0,903

(80oC), iu ny chng t ht nano vng to ra trong dng dch kh nhiu. Khi tip tc

tng nhit ln 90oC th hp thu bt u gim t 0,903 (80oC) xung 0,622 (90oC).

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Nguyn nhn l do khi tng nhit qu mc gii hn ca phn ng, cc ht nano sau khi

hnh thnh, chuyn ng va chm hn n to thnh ht kch thc ln hn lm gim s

lng cc ht nano vng nn hp thu gim. Vy da vo kt qu UV-Vis, vi t l

nHAuCl4: nvitaminC = 10:5, thi gian phn ng 240 pht, pH = 4,5, nhit thch hp

tng hp ht nano vng l 80oC.

3.3. Kt qu phn tch TEM ca nano vng chitosan

Hnh 4: nh TEM ca mu nano vng chitosan (a) mu 4t, (b) mu 10n, (c) mu 3p.

4.a: Dung dch nano vng chitosan iu ch 240 pht, 80oC, nHAuCl4/nvitamin C = 6:5, pH = 4,5.

4.b: Dung dch nano vng chitosan iu ch 240 pht, 80oC, nHAuCl4/nvitamin C = 10:5, pH = 4,5.

4.c: Dung dch nano vng chitosan iu ch 240 pht, 80oC, nHAuCl4/nvitamin C = 10:5, pH = 5,0.

Kt qu TEM (4.a) cho thy kch thc ht phn b trong khong 6 7nm vi t

l nHAuCl4/nvitamin C = 6:5, pH = 4,5; cng ti pH ny khi tng t l

nHAuCl4/nvitaminC = 10:5 th a s ht phn b trong khong 8 9nm (hnh 4.b). pH

cng nh hng rt ln n s hnh thnh ht nano vng chitosan vi cng t l

nHAuCl4/nvitamin C pH tng t 4,0 n 5,0 th kch thc ht tng t 8 9nm (hnh 4.b)

n 10 12nm (hnh 4.c). Cc kt qu trn nh TEM kh ph hp vi cc kt qu UV

Vis c ghi nhn trn.

(a) (b)

(c)

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3.4. Kt qu phn tch XRD nano vng chitosan

Hnh 1.5: Gin XRD nano vng chitosan mu 6n (Dung dch nano vng chitosan iu ch 240 pht, 80oC, nHAuCl4/nvitamin C = 10:5, pH = 5,0).

Kt qu phn tch nhiu x tia X trn hnh 1.5 cho thy dy nh ph, cng cc

nh hon ton ph hp vi ph chun XRD ca kim loi vng bao gm cc nh d =

2,35535 (2 = 38,20); d=2,04035 (2 = 440); d=1,44350 (2 = 64,60); d=1,23137 (2 =

77,60) tng ng vi cc mt ph ng 111 , {200}, {220}, {311}.

4. KT LUN

ch to thnh cng dung dch nano vng trong mi trng chitosan vi cht kh

vitamin C. kho st cc yu t thi gian, t l nHAuCl4/nvitamin C, pH, nhit v xc

nh iu kin thch hp nht ch to nano vng chitosan l 240 pht, 80oC, pH =

5,0, t l nHAuCl4/nvitamin C = 10:5. Cc kt qu phn tch ha l: UV Vis, TEM, XRD

ca cc ht nano vng kh ph hp vi nhau: UV Vis cho nh hp thu v tr t 518nm

n 524nm; gin XRD cho thy cc nh c trng cho cu trc tinh th vng, nh TEM

cho bit kch thc ht nano vng chitosan phn b kh ng u khong 10 12nm.

Abstract

In this study, gold nanoparticles was synthesized by reduction method with the

presusor HAuCl4, vitamin C reductant and chitosan as protectant agent. The effect of

reaction time, nHAuCl4/nvitamin C ratio, pH, temperature was investigated. The properties

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of gold-chitosan nanoparticles was analyzed by UV-Vis, XRD, FE-SEM and TEM

technique. Gold-chitosan nanoparticles solution was used in cosmetic production.

TI LIU THAM KHO

[1].Graham Allan, G.; Peyron, M. Carbohydr. Res. 1995, 277, 273282.

[2].Graham Allan, G.; Peyron, M. Carbohydr. Res. 1995, 277, 257272.

[3]. Schatz, C.; Viton, C.; Delair, T.; Pichot, C.; Domard, A. Langmuir 2003, 19,

9896.

[4].V. Dodane, D. Vilivalam, Pharmaceutical applications of chitosan,Pharm. Sci. Technol.

Today 16 (1998) 246253.

[5].W. Paul, C. Sharma, Chitosan a drug carrier for the 21st century,S.T.P, Pharm. Sci. 10

(2000) 522.

C VN KHOA HC SINH VIN THC HIN

PGS. TS Nguyn Th Phng Phong Hunh Th Cm Quyn