Tap chi Hoa hgc,
T. 48(4), Tr. 409 - 413, 2010
HOAT TINH DIET KHUAN CUA NANO BAC VA NANOCOMPOZIT
^• • •
Ag/AljOa OUOC KET TUA DIEN HOA
De'nTda scan 4-7-2008
NGUYEN CONG PHUC, NGUYEN DUC HUNG Vien Hod hgc - Vgt lieu, Vien Khoa hgc vd Ky thuat quan su
ABSTRACT
Anodic aluminium oxide (/SAO) membrane has uniform parallel pores and high pore density.
The pore diameter is controllable according to practical needs. Ag nanowires have been produced by Aternating Current (AC) electrodeposition in porous AAO^ template. So rumocompozit films consisting of regularly ordere Ag nanowires embedded in AAO templates. The composition and nanostructures of meterial was determined by SEM. XRD, EDX methods. The results of studying have showed nanocomposite Ag/Al20s demonstrated a stronger antibactericial activity than AI2O3 in air and water.
I - MO DAU
Ngay nay cdng nghe nano da trd thanh mdt hudng nghien ciiu miii nhgn phat trien tren the gidi. Vgt lieu nanocompozit hay vgt lieu composite co cdu true nano trong dd chi cd mdt phin cua vat lieu cd kfeh thudc nanomet, hoac ciu tnic cua chung cd nano khdng chiiu, mdt chieu, hai chiiu dan xen lin nhau dang dugc nghien ciiu va phat trien ung dung rit rdng rai
[ ! ] • . - .:• ..: ' , • : ; • ; , ' -,.
Bac tit xua da dugc ua chugng lam dd diing hoac trang siic nhd dac tfnh khu triing nhung cac mat hang bang kim loai bac nguyen chit hoac ma bac la rit dat. Tuy nhien tao dugc vat lieu vdi hat nano bac la mdt phuang phap thfch hgfp d i khai thac tfnh chit k h i triing, diet khuin cua bac nen nghien ciiu che tao nanocompozit Ag/AljOj va khao sat tfnh nang diet khuin nham khao sat cac yiu td anh hudng quyet dinh den cau true vat lieu, ciing nhu thu nghiem kha nang diet khuan cua nano Ag trong compozit vdi AI2O3 la cin thiit [2].
II - THUC NGHIEM 1. Nguyen lieu - Hoa chat
- Hgp kim nhdm - silic
- Hoa chat: H2SO4, HNO3, NaCI, NaOH, KOH, H2C2O4, AgN03... diu thudc loai tinh khiit PA cua Viet Nam, Trung Qud'c, Nga, Diic.
- Mdi trudng thif nghiem vi sinh:
+• Thanh phin thach Saburo: glucose (20 g/1), pepton (10 gA), agar (20 g/1).
+ Thach thudng nudi cly vi khuan Bacillus subtilis: cao thit (5 gA), N a Q (5 g), pepton (10 g/1), agar (20 g/1).
+ Nudi cay chiing vi khuin Escherichia.coli PT0021 trong mdi trudng Mocknkey: pepton (20gA), lactose (10 gA), NaCI (5 g/1). Bile salt mixture (1,5 g/\), neutral red (0,03 g/\), agar (20 gA).
2. Phuong phap che tao
v a t lieu nanocompozit Ag/Al203 dugc che' tao bang phuong phap dien hda [3 - 6].
- Giai doan 1 tao pha nin composite bing qua trinh and't hoa de c h i tao mang AI2O3 cd Id xd'p dat kich cd nanomet.
- Giai doan 2 kit tua ling dgng Ag trong Id xd'p mang nhdm oxit and't hda thu dugc d giai doan 1 bang phuang phap dien hda ddng xoay'
chiiu trong dung dich AgN03. t 3. Cac phuong phap nghien cufu
- Dudng kfnh Id xd'p cQng nhu hinh dang va kfeh thudc cua san pham ling dgng dien hdi dugc ehup anh SEM tren thiit bi S-4800 cua hang Hitachi.
- Phan tfch dinh tinh thanh phin hgp chat ciia vat lieu dugc tien hanh tren may nhiiu xa Ranghen SIEMENS D5005. Qua trtnh xit ly sd lieu da dugc chuang trtnh hoi vdi cac ma vach chuin do hdi tinh thi qud'c t i cung clp.
- Phuang phap do EDX d i xac dinh cac nguyen td va ty le phin tram ciia chiing cd trong vat lieu duac thuc hien tai Vien Khoa hoc Vat lieu -Vien KHCNVN.'
- Phuang phap phan tfch vi sinh dua tren cd sd cic te bao con kha nang sdng sdt sau khi tiep xuc vdi vat lieu gap diiu kien thuta Igi khi nudi cly chiing tren mdi trudng thach dinh dudng dugc tiin hanh tai phdng Thf nghiem Sinh hgc - Vien Hoa hgc - Vat lieu. Dich huyin phd cua hai chung vi sinh vat B. subtilis va E. coli dugc hiit bang pipet 20 ml cho vao cac hop long thuy tinh roi dung panh gap cac miu vat lieu cho ngap trong dich huyin phu cua titng loai vi khuin tren. Kiim tra mat dd t i bao sau 24 gid d i trong diiu kien nhiet dd phdng va xac dinh kha nang sdng sdt cua te bao cua cic dich huyen phu vi khuin da dugc xu ly bdi cic miu tren.
Hiit 5ml dich huyin phii da dugc xu ly len cac dia thach Saburo roi trai diu len mat dia. U dia thach da trai dich dugc xii ly d 30°C trong 24 gid roi kiim tra sd lugng khuin lac tuong ling vdi cac te bao sdng sdt.
Ill - KET QUA v A T H A O L U A N
1. Tao pha nen compozit bang mang nhom andt hoa
Qua trtnh and't hoi dien hoa nhdm va hgp kim nhdm d i tao mang nhdm oxit vdi cac Id xd'p cd kfeh thudc nanomet da dugc nhieu d i tai trong va ngoai nude d i cap nghien ciiu [5, 6].
Cac thdng sd nhu mat do ddng, nhiet dd, ndng do axit sunfuric, thdi gian and't hoa cd anh hudng din chiiu day va ciu tnic ciia mang nhdm oxit and't hoi. D i mang nhdm oxit cd dudng kfnh Id xd'p cd nanomet, che dd and't hoa qua khao sat xic dinh dugc la Cjj gQ = 1 8 0 g/1;
T = 20°C; DA = 1 A/dm^ t = 60 phiit. Dudng kfnh Id xd'p trung binh cua san pham tao thInh xic dinh tit cac anh SEM khoang 15 nm con chiiu day mang nhdm oxit tuang ung chiiu sau cua Id xdp do dugc la 15 pm.
2. Cau true cua Ag trong mang nhdm oxit Do Id xd'p mang AI2O3 cd dudng kfnh nanomet nen kfeh thudc cua bac kim loai kit tua ling dong d c h i dd: U^c = 12 V, thdi gian t = 4 phut, CAgN03 = 2 gA, TpHong (27°C) se bi khdng c h i bdi kich thudc Id xd'p nen anh SEM xac dinh cung se cd kfeh thudc nanomet. That vay, sau khi tiy ldp mang AI2O3 bing dung dich NaOH 5 gA ta cd thi quan sat dugc tren anh SEM (hinh 1) san phim dang sgi cua bac kim loai da dugc kit tua tren mang. Kich thudc cua cac sgi Ag tuong ddi diu vdi dudng kfnh tmng binh khoang
1 0 - 1 5 n m .
3. Thanh phan ciia Ag liet tua lang dgng trong 16 xdp
Ban chit cua qua trtnh ling dgng dien hda la su khii catd't ion Ag* thanh Ag° d trong Id xdp cua mang nhdm oxit and't hda. CIc thdng sd cdng nghe cua qua tiinh dien cue se quyit dinh qua trinh khu chi xay ra trong Id xd'p cQng nhu tfnh chit va chit lugng cua san phim sgi nano bac. Bing ddng xoay chiiu 12V vdi ndng dd mudi bac thap se thuc hien dugc qua trtnh kit tua trong Id xdp mang nhdm oxit and't hoi.
Kit qua phan tfch EDX (hinh 2a) cho thay nanocompozit AglA^Oj, thu dugc bao gdm Ag dugc kit tua va cac nguyen td cd trong vat lieu nin hgp kim nhdm nhu: O, Al, Si, Fe. Ham lugng Ag trong Ag/AljOa da dat din 10,86%
trgng lugng sau'4 phiit kit tua.
410
a b Hinh 1: Anh SEM sgi nano bac (a) va diim (b) vdi thang do 500 nm
Element 0 Al Si Fe Ag Totals
Weight"/.
2 minute 49.27 46.24 1.48 0.19 2.82 100.00
4 minute 33.32 53,91 1.65 0.26 10.86 100.00
Atomic%
2 minute 63.16 35.15 1.08 0.07 0.54
4 minute 49.07 47.07 1.38 0.11 2.37
VNU-HN-SIEMENS D5005- Mau Ag-AI203-Ag20-Al- M5
g-..JV
a Scale 47609 d s Cigsor 3.640 keV (214 d s )
^ ^ ^ ^ * * ' ^ ' K v ^ ' * - » ^ , l w v ^ Y ' ^ ^ i
2-Theta - Scale
Hinh 2: Phd EDX (a) cua san phim Ag/Al203 kit tua sau 2 phut; 4 phut va Ranghen (b) cua sgi nano bac
Thanh phin pha cua Ag kim loai ling dgng trong Id xd'p mang AI2O3 dugc xac dinh bing phd Ranghen (hinh 2b) cho thiy thanh phin san pham kit tua trong Id xd'p ciia mang nhdm oxit ton tai ca d dang tinh the Ag kim loai.
4. Kha nang diet Ithuan cua nanocompozit Ag/Al203 trong Ichdng lihi
Qua hinh 3 so sanh kha nang diet khuin trong khdng khf cua miu san phim M l va miu tring M2 de ding nhan thiy tren b i mat Ip miu tring AI2O3 (M2) vi khuin va nim mdc phat triin nhiiu tren b i mat thach, chiing td t i bao vi sinh vat khdng bi tieu diet. Tren b i mat thach dugc ap bdi miu Ag/Al203 (Ml) sd lugng khuin lac
hiu nhu khdng cd chiing td cic t i bao vi sinh vat da bi tieu diet khi bim dfnh tren b i mat vat lieu nanocompozit Ag/Al203.
5. Kha nang diet khuan cua nanocompozit Ag/AlzOs trong moi trudng nude
Kit qua d bang Iva hinh 4 cho thiy vdi mat do vi khuin B. subtilis dugc cay trong dich la 1500CFUAidp, E. coli II 500 CFUAidp miu M l nanocompozit Ag/Al203 cd kha nang diet khuan tdt vdi ca hai chung vi khuin B. subtilis va E. coli. Vdi vi khuan B. subtilis ta thiy miu tring khdng cd hieu qua xu ly, nhung ddi vdi vi khuan E. coli ca miu tring ciing cho thay cd hieu qui xii ly nhung d miic ty le thip 56,8%
con miu nanocompozit Ag/Al203 dat 99,4%.
Bang 1: Kit qua xit ly B. subtilis va E. coli tren nanocompozit Ag/Al203 Miu
hop Idng chua cly dich hop Idng da cly dich
M l (Ag/Al203) M2 (AI2O3)
B. subtilis (CFU/hdp)
0 1500
204 1500
E.coli PT0021 (CFU/ hdp)
0 500
3 216
Ty le chit (%) B.subtilis
- 0 86,4
0
E.coli - 0 99,4 56,8
"-^/imn f
tinh 3: So sinh kha nang diet khuan cua nanocompozit
Ag/Al203 (Ml) va AI2O3 (M2) trong khdng khf
6. Kha nang diet lihuan cua sgi nano Ag Nanocompozit Ag/Al203 sau khi ling dgng dugc hoa tan nin nhdm oxit bing dung dich NaOH 10% de tach lay cac sgi nano Ag trong nude cat (M3) vdi ndng do 100 mg/100 ml nude.
Kha nang diet khuan cua miu M3 ciing dugc thu nghiem ddi vdi hai loai vi khuin B. subtilis va E. coli. Hai loai vi khuan tren duac
Hinh 4: So sanh kha nang diet khuan cua nanocompozit Ag/Al203 (Ml) va AI2O3 (M2) trong nude: 1. hop long cay dich, 2. x6 ly bang
AI2O3, 3. xut ly bang Ag/Al203
a. hdp Idng cly dich B. subtilis 1500CFU/hdp . b. hdp Idng cay dich E. coli 500CFU/hdp nudi cl'y va lie 130 vdng/phut, sau 24 gid cho vao mdi trudng thach cd bd sung agar da khit triing cua cac hdp long thuy tinh vd triing. Vdi 2 ml dung dich M3 cho vao cac gieng thach da khoan rdi d i tu lanh 4°C de cac sgi nano Ag khuich tan vao thach trong khoang 24 gid.
Trong tu im 30°C vdi thdi gian 24 - 48 gid da quan sat thiy vdng vd trung (hinh 5) chiing td cac vi khuin da bi lic c h i khdng the phat triin.
412
Hinh 5: So sanh vdng trdn khing khuin E. coli va B. subtilis cua miu M3
rV - KET LUAN
- Sgi nano Ag kim loai dugc kit tua ling dgng trong Id xdp cd kich thudc nano ciia mang AI2O3 tren n,in vat lifu kim loai hgp kim nhdm. Kfeh thudc sgi nano Ag bi gidi han bdi dudng kfnh Id xd'p, chiiu day mang va dat dugc dudng kfnh trang binh cd 10 - 15 nm va chiiu dai 15 |am.
- Vat lieu nanocompozit Ag/Al203 trSn bi mat nhdm cd kha nang diet khuin ca trong khdng khi (nim mdc, vi khuin) va trong mdi trudng nude vdi hai chung vi khuin B. subtilis (loai vi khuin cd bao ti) va E. coli (loai vi khuin khdng cd bao tit) dat hieu qua cao.
- CIc sgi nano kim loai Ag dugc tach ra rieng re khdi vit lieu nanocompozit ciing cd kha nang diet hai chiing vi khuin B. subtilis va E. coli rit tdt.
T A I LIEU THAM K H A O
1. Nguyin Xuan Chinh, Vii Dinh Cu. Cdng nghe nano dieu khiin din titng phin tit nguyen til, NXB khoa hgc va ky thuat. Ha Ndi (2004).
2. Virginia Davis, Characteristics and a|yplications of antibacterial nano-silver.
Department of Chemical Engineering Auburn University (2006).
3. Nguyin Diic Hiing, Dang Van Dudng, Ngd Hoang Giang, Trin Ngge Tam. Tap chf Khoa hoc va Cdng nghe, tap 38, Ha Ndi (2000). '
4. H. Lin, F. Favier, K. Ng, MP.Zach,
R.M.Penner, Size-selective electrodeposition of meso-scale metal
particles - A general method. University of California (2001).
5. Huixin He, Nongjian J.Tao, Electrochemical Fabrication of Metal Nanowires, Chemistry Department, Rutgers University, Department of Electrical Engi.^eering, Arizona State University, USA (2003,.
6. Kaniyankandy, Sreejith, J. Nuwad, C.
Thinaharan, G. K. Dey, C. G. K. Pillai.
Nanotechnology, Vol. 18(12), 125610.
Lien he: NguySn Diitc Hiing Vien Hda hgc - Vat lieu
Vien Khoa hgc Ky thult Quin su 17 Hoang Sam, Ciu Gia'y, Ha Ndi Email: [email protected]
