JOURNAL OF SCIENCE OF HNUE Natural Sci., 2014. Vol. 59. No. 4, pp. 54-60 This paper is available online at http://stdb.hnue.edu.vn
SLf DUNG THUOC THlJ l-(2-PYRIDYLAZO)-2-NAPHTOL(PAN) DE XAC DINH NKH) BANG PHUONG PHAP TRAC QUANG - CHEMOMETRIC
N g u y e n D i i c Vifcfng^ v a N g u y e n D i i c M i n h ^
^ Khoa Kl thuat vd Cdng nghe, TrUdng Dai hgc Quang Binh
"^TrUdng Trung hgc pho thdng Quang Ninh. Quang Binh
Tom tat. PhUdng phap trie quang chemometric da xac dinh dUOc ham luong Ni{II) vdi thuoc thU tao phUc PAN khi cd mat chit hoat ddng be mat Tween 80 cho kSt qua cd do lap lai cao (RSD = 2,11%). Dp hap thu quang ciia phUc Ni-PAN dat gia tri cao nhai tai budc sdng A = 569 nm. Gia tri pH thich hop cho sU tao phUc giUa Ni(II) va PAN la 5. Nong do Tween thich hdp nhk la 5%.
Tii khda: PhUdng phap trac quang - chemometric, thuoc thU tao phUc PAN, Ni(II).
1. Mcf dau
Niken la nguyen td vi luong rat can thiet cho ddi sdng ciia cac loai thuc vat, ddng vat bac cao, la kim loai quan trong trong cac nganh cdng nghiep. Khi thieu niken se xay ra mot so benh nhU viem da, lam bien dang xUdng nhUng nSu thCfa niken cd the gay ung thu phdi va nhoi mau cct tim [4].
Thudc th^ PAN cd kha nang tao phiJc mau vdi nhiSu ion kim loai nen thudng diing trong phan tich trac quang [1-4]. Khi tao phiic vdi ion Ni{II), phUc Ni-PAN khdng tan trong nudc ma tan trong mdi trUdng cd chUa chat hoat ddng be mat nhU Tween 80 [4]. Ben canh dd, PAN cdn la mot thudc thiJt cd mau va hSp thu d nhiJng budc sdng gan vdi phiic eiia nd dan den sU xen phii lan nhau giiJa phd cua thudc thuf va phUc. Khi thudc thii dU se hap thu d budc sdng gin vdi phUc nen ciing trd thanh mot c i u tii cd vai trd nhu la phiic.
Vi vay, mudn xac dinh cac kim loai cd phd' cua phiic va thuoc thif xen phii nhau ngUdi ta thudng dung phUcfng phap chiet - trie quang de tach phiic ra khoi thudc thii [1]. NhUng phUdng phap chidt - trac quang cdn gap mot sd vin de nhU: phai stf dung den lUOng dung mdi Idn ma mot s6 dung mdi cd the gay doc hai cho ngudi phan tich va moi trUdng, qua Ngay nhan biii. 23/1/2014. Ngay nhan dang: 3/5/2014
Tac gia hen lac: Nguyin Diic Vifdng, dia chi e-mail [email protected]
Sif dung thudc thif I-(2-pyridylazo)-2-naphtol (PAN) dexdc dinh Ni(fl) bdng phuang phdp...
trinh tach cCing cd the khdng tach hoan toan dUpc, quy trinh phan tich phiic tap, qua nhieu giai doan de gay sai so Idn, thdi gian ehiSt keo dai.
Vi vay vin de dat ra la phai lam sao cho quy trinh phan tich ddn gian hdn nhUng v5n phai dam bao cd do dung va do chinh xac cao. Bai bao nghien ctiu sii dung thudc thuf l-(2-pyridyIazo)-2~naphtoI(PAN) de xac dinh Ni(II) bang phUdng phap trac quang - chemometric nham muc dich tim ra quy trinh phan tich ddn gian va cd do tin cay.
2. Noi dung nghien cufu 2.L ThUc nghiem
* Hda chdt: Dung dich PAN (l-(2-pyridy!azo)-2-naphthol (Merck); Dung dich chuan gdc Ni^"^; Tween 80 {Polyoxyetilen (20) sorbitan monooleat, Cfi4Hi2402s, M = 1310 g/mol) dung dich 5% (v/v); Dung dich dem axit axetic - natri axetat pH - 4,8.
* Thiet bi: May do pH: WTW 330i/set; May trac quang UV - VIS Jasco V360 (Nhat Ban), dai bUdc sdng &o 200 nm - 900 nm, cuvet thiiy tinh cd chieu day I - 1 cm; ChUOng trinh Phoehuan.exe xac dinh, chUdng trinh SIMULANl.exe.
2.2. Ket q u a va t h a o l u a n
2.2.L Khao sat tinh cong tinh thuoc thu" PAN va phiic NI-PAN2 (ti le tao phiic 1 :2) Tien hanh pha che thudc thU PAN va phUc mau Ni-PAN^ rdi quet phd trong khoang budc sdng 400 - 700 nm. Khi tidn hanh tao phUc ndng do Ni(II) la 5.10"^'M, ndng do ciia P A N I a 2 . i 0 - ' ' M
PAN Ni-PAN, hh ly thuyet hh thuc te
Wave length (nm)
Hinh 1. Pho hdp Ihu cita PAN, phdc Ni-PAN-i vd pho ciia hdn hdp phdc vd thuoc thil dU theo li thuyet vd theo thi/c ti: PAN 1,00.10' ''M, Ni-PAN2 5,00.10 ''M
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Nguyen DiJc Vildng va Nguyin Diic Minh
Ket qua cho M y phiJc mau Ni-PANj va thuoc thii PAN co do hdp thu quang dat cue dai d cac budc song tUdng ilng la A„., = 569 nm va 470 nm. Pho cua phiic mau co tinh cong tinh (pho hap thu ciia h5n hop phtJc theo h' thuyet va theo thiic te trung nhau trong gidi han sai s6 cho phep (RE(%) = 0,064) nen chung toi sil diing phuong phap pho toan phan de xac dinh Ni(n). Muc dich S day la khao sat tinh cong tinh, con Icct qua khao sat cho th% 6 budc song 569 nm do hip thy quang la idn nhat, viec chpn gia tri cUc dai khong anh hudng d§n tinh toan.
2.2.2. K8t qua khao sat anh hudng cua pH den su hinh thanh philc chat KSt qua khao sat trong khoang pH til 3 din 8 thu duoc d Bang 1 va bieu dien tren Hinh 2.
Bdng 1. Kk qua khao sat anh hudng cda pH den sU hinh thanh phUc chdt pH
ANI-PAN2
(A = 569) 3 0,062
4 0,109
5 0,158
5 0,140
7 0,135
8 0,131
Ji-PAN, I
Hinh 2. Anh hudng cdapHdSn do hap thu quangphUc Ni-PAN^
Hinh 2 cho IhSy do hap thu quang cCia philc Ni-PANj tang dSn gia tri circ dai d gia tri pH = 5 sau dd giam xuong khi tang cac gia trj ciia pH. "Vi vay, nhdm tac gia da chpn gia trj pH - 5 cho cac thi nghiem nghien ciiu.
2.2,3. Khao sat su on dinh cua phiic tao thanh theo thii gian
Ti6n hanh phan ling tao philc giiia Ni(n) va PAN, de yen trong 20 phut rai dem ghi phd hSp thu trong khoang budc sdng 400 - 700 nm.
Sddung thudc thit P(2-pyridylazo)-2-naphlol (PAN) de'.uic djnh Ni(Il) bdng phuang phdp...
Bdng 2. Ket qua khao sat do hdp thu cua cdc phiic mdu theo thdi gian Thbi gian
(phut) 1 5 10 15 20 25 30
ANI-PANS (A = 569)
0,077 0,117 0,139 0,151 0,158 0.159 0,159
Thbi gian (phut)
35 40 45 50 60 80 100
A.V,-F/1JV2 (A = 569) 0,158 0,156 0,152 0,150 0,149 " ""
0,146
~"~6M2
Hinh 3. Khao sat do ben ciia cdc phiic mdu theo thdi gian
TU Bang 2 va Hinh 3, chung tdi nhan lh% trong khoang thdi gian khao sat 100 phut, phUc mau Ni-PAN^) hinh thanh kha cham, do hap thu quang ciia phUc on dinh trong khoang thdi gian tU 20 den 35 phiit nen tdi chgn khoang thdi gian quet phd la sau khi tao phiic mau dUdc 20 phut.
2.2.4. Pho UV - Vis cua thuoc thu' PAN
Vice xac dinh phd UV-Vis ciia thudc thiif PAN duoc tien hanh nhu sau:
Cho vao 2 binh dinh mtic 25 mL. Binh 1 la mau trang: cho vao 3 mL dung dich dem axetat cd pH = 5, I inL Tween 80 5% rdi dinh mUc den vach bang nude cat 2 Ian. Binh 2 la dung dich chuan PAN: cho vao 3 mL dung dich dem axetat cd pll = 5, 1 mL Tween 80 5%, 2,5 mL dung dich PAN I0"^M roi dinh mdc den vach bang nude cai 2 lan.
Tien hanh quel phd ciia dung dich thudc thi'r PAN trong khoang budc sdng 400 - 700 nm ta thu dUdc phd chuan ciia dung dich PAN.
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Nguyen Diic Vupng va Nguyen Diic Minh - PAN I
Hinh 4. Pho UV-Vis cua thuoc thU PAN 1,00.10 ^iVf
2.2.5. Pho UV-Vis cua phuc Ni-PANj
Tien hanh xac dinh pho chuan ciia phiic Ni-PANj bang chUdng trinh Phoehuan.exe de tinh pho' chuan ciia philc Ni-PANj khi biet chinh xac lupng thuoc t h i dU.
Wave length (nm)
Uinh 5. Pho UV-Vis cuaphdc Ni-PANi 5,00.10^^'M (Nong do cuaphiic Ni-PANz Id 5,00.10'^'M, pho tinh toan hang chuong trinh Phoehuan.exe)
l.l.fi. Xac dinh Ni(II)) bang phiTOng phap trac quang - chemometric
Sau khi da xac dinh dUdc phd chuan cua thudc thiif PAN va pht^c kim loai thi ta se xac dinh dUdc ham lUdng cac ch5t cd mat trong hdn hdp gdm phUe ciia kim loai va thuoc thii du bang chUdng trinh da difdc lap s&n la SIMULANl.exe.
Su dung ihudc thu I •(2-pyridylazo)-2-naphtol (PAN) dexdc dinh Ni(II) bdng phUOng phdp...
Bdng 3. Ndng do cua kim loai Ni(II) vd PAN^^
Cau tuT Cph^hSdO-^M) C,,„,,i,S,(10-''M)
RE (%)
Ni(II) 5,00 4.94 1,2
PANd„
10,00 10,04 0,4
Bang 3 cho thay ndng do kim loai Ni(n) xac dinh dUdc bang phUdng phap trSc quang - chemometric thdng qua chUdng trinh Simulanl.exe nam trong khoang sai sd cho phep. Sau khi tao phUc vdi Ni(II) theo ti le 1:2, lUdng thuoc th^ PAN cdn du theo li thuyet la IO,00.10""M sau dd dUa vao phan mem tfnh toan dUdc lUdng dU la 10,04.10"^M.
Luong thudc thii PAN cho vao ban dSu la 20,00.10"^M). Ket qua tren la chap nhan dUdc.
2.2.7. Danh gia do tin cay cua phitdng p h a p
* Do lap lai
Bang 4. Ket qua tinh RSD (%) khi xdc Cau tur
Ni(ll)
" " P A N j ; " '
ClMnlhSydO-'M) Lan 1
4,83
"10,20 ~ Lan 2
5,00 10,00
Lan 3 5,02 9,93
dinh kim loai i^i(H) vd ( l O - ' M )
4,95 10,04
RSD
(%)
2,11 1,40
PAN,,, RSD„
(%)
12,57
" " r i " , 2 4 " "
Dua vao kdt qua tinh RSD ta thSy gia tri RSD < RSDIl nen ket qua do cd dp lap lai tdl. Ben canh dd, sai sd ciia phep do nhd (Bang 3) nen ta cd the xac dinb dUOc kim loai Ni(II) bang thudc thii PAN thdng qua chUdng trinh SIMULANl.exe
* Khoang tin cay
Bdng 5. Khoang tin cay khi xdc dinh kim loai Ni(H) vd PANd,(
Kim loai Ni(ll) I'AN'
:f ( l O ^ ' M ) 4,95 10,04
e 0,26 0,11
p. (10-°M) 4,69-5,21 9 , 9 3 - 10.15
Bang 5 cho thay nong do ctia kim loai Ni(II) khi xac dinh bang phUdng phap trac quang - chemometric nSm trong khoang tin cay. Ket qua do la ch4p nhan dUdc.
3. Ket luan
Qua nghien cUu chung tdi da khao sat tim dugc cac dieu kien thich hdp de xac dinh Ni(Il) khi dung du thuoc thiif PAN, trong dd phUc cua kim loai vdi PAN cd phd hap thu xen pho vdi thudc thU dU.
Xiic dinh dUdc phd chuan ciia cac phUc Ni-PANj bang cbUiJng trinh Phocbuan.exe
Nguyen DUc Vudng va Nguyen DUc Minh khi cho thudc thii dU so vdi kim loai.
Da xac dinh dUdc Ni(U) khi cho dU thuoc thuf PAN bang chUdng h-inh SIMULANl.exe. KSt qua do la on dinh va nam trong khoang sai sd cho phep, cd the ch3p nhan dUdc.
TAI LIEU THAM KHAO
[1] Chu Dinh Binh va Pham Luan, 2006. Nghien cdu phan dng tao phiic chdt gida Co(li) vd Ni(Il) vdi thudc thu PAN trong mdi trudng Mixen, danh gid khd ndng dp dung vao phan tich ddng thdi Co(U) vd Ni{II). Tap chi phan tich Hoa, Ly va Sinh hoc, 11(4).
[2] Trdn Tii Hieu, 2003. Phan tich trac quang. Nxb Dai hpc Qudc gia Pla Ndi.
[3] A. Gallardo Melgarejo, A. Gallaardo Cespcdes, J. M. Canopavon, 1989.
Simultaneous determination of Nickel, Zinc and Copper by second-derivative spectrophotometry using 1-{2-pyridylazo)-2-naphthol us reagent. Analyst, Vol, 114, pp. 109-111.
[4] G. A. Shar, G. A. Soomro, 2004. Spectrophotometric determination of Cobalt(!l), NikeUII) and Copper(ll) with J-(2-pyridylazo)-2-naphthol in micellar medium. The nucleus, 4] (1-4), pp. 77-82.
ABSTRACT
Using l-(2-pyridylazo)-2~naphthol (PAN) reagent to determine Ni(H) when employing the chemometric-photometric method
A spectrophotometric determination of Ni(n) wa.s carried out using PAN as the complex reagent in aqueous phase with surfactant Tween 80. 'fhe results had a high degree of repeatability (RSD - 2.11 %). Absorbance was best at a wavelength (A,^,;, of 569 nm).
The pll value appropriate for Ni(n) and PAN complex formation is five. The optimal Tween concentration is five percent.
