AS245: Bachelor in Science Applied Chemistry Title: Analysis of plant tissue (AAS)
Analysis Course: Spectrochemical Methods of Analysis (CHM580) Name: Mohamad Nor Amirul Azhar ! "amis Matrix no:
#0$%&%'%% (AS#%5 S)
Date of experiment: #5th March #0$5 Date of submission: 8th April #0$5 Group members: $! Nurnailah t! Noorazlan
#! Nor Amirah t! Ahmad Azuan ! Noramira t! Saad It is my responsibility as a student of iTM to ad!ere to trut!fulness and a"oid dis!onesty# fraud or de$eit of any type in $onne$tion %it! %rite up and $ondu$t of t!is experiment& Si'nature:(((((((((( Date:
TIT)*:
etermination of iron (*e) and cadmium (Cd) in plant tissue (spinach)!
A+ST,ACT:
+he e,periment -as done to determine the cadmium (Cd) and iron (*e) in spinach y usin. -et di.estion method for the sample preparation! +he amount of those metals presence in the spinach -as determined y usin. the atomic asorption spectroscopy (AAS) instrument! +he since the concentration of analytes in sample are in small amount/ the standard addition method -as applied! *rom the caliration cure plotted/ the concentration of analytes is 1no-n y e,trapolatin. the strai.ht line line unti untill the the ,2in ,2inte terc rcep eptt -her -here e the the aso asor ran ance ce is zero zero!! +he +he conc concen entra tratio tion n of cadmium in spinach sample is $!$'M -hile the concentration of iron in spinach sample is$!%'M!
INT,-DCTI-N:
3ene 3enera rally lly the the atom atomic ic aso asorp rpti tion on spec spectr tros osco copy py is an inst instru rume ment nt that that used used for for 4uanti 4uantific ficati ation on of metal metal elemen elements ts that that presen presentt in the sampl sample! e! +he +he conce concentr ntratio ation n measured is ased on the asorption of the radiation either from line source such as hollo- cathode lamp or continuum source! ach element -ill asor radiation at their specific -aelen.th from radiation source! +he sample introduction is normally in li4uid form for flame atomizer! +he sample is conerted into the form of free atoms efore efore it can asor asor the radiati radiation on from from the radiat radiation ion source source!! Atomi Atomic c asorp asorptio tion n Spectr Spectrosc oscopy opy (AAS) (AAS) instru instrumen mentat tation ion consis consists ts of radiat radiation ion source source// -aele -aelen.t n.th h selector/ sample container/ container/ detector and the si.nal processor and readout! Sample used -as spinach tissue that contains cadmium and iron! Cadmium is not re.arded re.arded as essential essential to human life/ different different -ith iron that is an essential essential mineral mineral that that help helps s tran transp spor ortin tin. . o,y. o,y.en en thro throu. u.ho hout ut ody ody!! ,ce ,cess ss cadm cadmiu ium m e,po e,posu sure re produces aderse health effects on human ein.s! 6et di.estion method is used to e,tract the analyte out from the sample y treatin. -ith concentrated acid! +he standard addition method is used -hen the concentration of analyte in the sample is ery ery lolo- -hil -hile e matr matri, i, is hi.h hi.h!! By usin usin. . the the stan standa dard rd addi additi tion on meth method od// the the
concentration of the sample is added -ith 1no-n concentration solution in order to increase the si.nal mean-hile accountin. -ith matri, effect! -+.*CTI/*:
etermination of cadmium and iron in spinach y usin. -et di.estion method and also to 1no- the amount of the metals (cadmium and iron) present in the plant tissue!
*01*,IM*NTA):
A! 7reparation of cadmium (Cd) standard $! 5m9 of $00ppm $00ppm of Cd stoc1 stoc1 solutio solution n -as pipetted pipetted into into 50m9 50m9 olum olumetr etric ic flas1 and -as added -ith de2ionized -ater until the caliration mar1 to ma1e $0ppm Cd solution! C$:$; C#:# $00:$ ; $0(50) :$ ; 5m9 #! $0ppm $0ppm Cd solution solution -as pipette pipetted d into & different different 50m9 50m9 olumet olumetric ric flas1s flas1s to ma1e the follo-in. concentration Standard $on$entration
/olume of Cd 3ppm#
m) < = 0!0 0!0 < = 0!# $!0 < = 0!% #!0 < = 0!& !0 < = 0!8 %!0 < = $!0 5!0 Sample calculation: standard 1
Blan1 Standard $ Standard # Standard Standard % Standard 5
C 1V 1= C 2 V 2 2V 2 10V 1 = 0.2(50) V 1 = 1.0mL
! ach of the the olumetri olumetric c flas1s flas1s -as mar1 mar1 up -ith -ith de2ionized de2ionized -ater -ater until until the 50m9 caliration mar1! B! 7reparation of iron (*e) standard
$! 5m9 of $00pp $00ppm m of *e stoc1 stoc1 solution solution -as pipett pipetted ed into 50m9 50m9 olume olumetri tric c flas1 and -as added -ith de2ionized -ater until the caliration mar1 to ma1e $0ppm Cd solution! C$:$; C#:# $00:$ ; $0(50) :$ ; 5m9 #! $0ppm $0ppm *e solution solution -as pipette pipetted d into & different different 50m9 50m9 olume olumetric tric flas1s flas1s to ma1e the follo-in. concentration Standard
/olume of Cd 3ppm#
$on$entration < = 0!0 < = $!0 < = $!5 < = #!0 < = #!5 < = !0
m) 0!0 5!0 '!5 $0!0 $#!5 $5!0
Blan1 Standard $ Standard # Standard Standard % Standard 5
Sample calculation: standard 1 C 1V 1= C 2 V 2 2V 2 10V 1 = 1.0(50) V 1 = 5.0mL
! ach of the the olumetri olumetric c flas1s flas1s -as mar1 mar1 up -ith -ith de2ionized de2ionized -ater -ater until until the 50m9 caliration mar1! C! 7reparation of sample $! ay $ a! +he spina spinach ch -as -as cut to smalle smallerr size and and -as dried dried in oen oen at $00>C $00>C oerni.ht to remoe -ater moisture in the plant tissue!
#! ay # a! #!?%''. #!?%''. of dried dried spinach spinach leaes leaes -as put put into a ea1er ea1er and and #020m9 #020m9 of concentrated nitric acid solution (&5@) -as added into i t! ! +he ea1er ea1er -as left left oern oerni.h i.ht! t! ! ay a! +he mi,ture mi,ture -as -as heated heated in the the fume hood hood until until the red red fume (N (N#) -as released! ! After the the red fume -as -as released released// the mi,ture mi,ture -as let let to cool in the the fume hood! c! #m9 of of hydro hydro.en .en pero,i pero,ide de solutio solution n (0@) -as added added into the cooled cooled mi,ture!
d! +he mi,ture mi,ture -as heated heated a.ain a.ain allo-in allo-in. . eaporatin. eaporatin. to to a small olume! olume! e! +he sample sample -as filtered filtered and and transferred transferred into into a #50m9 #50m9 olumetr olumetric ic flas1! flas1! f! e2ionize e2ionized d -ater -ater -as added added until the the #50m9 #50m9 caliration caliration mar1 (calc (calculate ulate for the dilution factor)! CA+DN al-ays add HN to the tissue samples and allo- this mi,ture to di.est efore addin. H ##! H## reacts e,plosiely -ith untreated or.anic matter! ! perat peration ional al instru instrumen ment t $! +urn +urn on ar.on ar.on .as .as and and compre compress ss air! air! #! +urn +urn on spect spectrom romete eter! r! ! pen pen soft-a soft-are re 6in9a 6in9a# # *or *or AA! AA! %! +urn +urn on lamp lamp (idl (idle) e)!! 5! Select Select method/ ne-/ ne-/ -rite method method name/ name/ select select element element to e analysed analysed!! &! Select Select settin./ settin./ time (!0)/ delay ($82#0)! ($82#0)! '! Sele Select ct sam sampl ple/ e/ ne neer er!! 8! Select Select caliration/ caliration/ e4uatio e4uation n (nonlinear (nonlinear throu.h throu.h zero)/ zero)/ unit (ppm)! (ppm)! ?! Select Select standard standard concentr concentration ation// fill -ith stand standard ard names! names! $0!Select file/ sae as/ method/ -rite method name! $$! $$! Chec1 lamp/ close! $#!+urn on flame! $!Select auto/ analyse/ reuild list/ analyse all! ,*S)T:
A! Cadmium (Cd) standards < = 0!0 < = 0!# < = 0!% < = 0!& < = 0!8 < = $!0
Con$entration ppm 0!$#0 0!$8 0!$&# 0!$8# 0!#0? 0!#$'
Graph of Absorbance vs standards Cd 0.25 f(x) = 0.1x + 0.12 R² = 0.99
0.2 0.15
Absorbance
0.1 0.05 0 0
0.2
0.4
0.6
0.8
1
1.2
(sample + x) standards
y ; m, = c y ; 0!$0#&, = 0!$# 6hen y ; 0/ ,2intercept ; E 0!$0#&, ; 20!$# < ; 2$!$' *rom .raph/ the concentration of cadmium in sample is $!$'M B! Dron (*e) standards < = 0!0 < = $!0 < = $!5 < = #!0 < = #!5 < = !0
Con$entration ppm 0!0#$ 0!0%5 0!055 0!0&# 0!0&8 0!0'#
Graph of Absorbance vs standards Fe 0.08 f(x) = 0.02x + 0.03 R² = 0.96
0.07 0.06 0.05
Absorbance
0.04 0.03 0.02 0.01 0 0
0.5
1
1.5
2
2.5
3
3.5
(sample + x) standards
y ; m, = c y ; 0!0$', = 0!0#55 6hen y ; 0/ ,2intercept ; E 0!0$', ; 20!0#55 < ; 2$!5 *rom .raph/ the concentration of iron i n sample is $!%'M!
DISCSSI-N:
+he standard addition method is used ecause the matri, effect is too hi.h/ so that the sample sample is spi1e spi1ed d -ith -ith the 1no-n 1no-n stand standard ard conce concentr ntrati ation! on! After After plottin plottin. . the caliration cure/ the concentration of the analyte in the sample can e determine y e,trapolatin. until the ,2intercept! +he ,2intercept is at -hich the olume of standard rea.ent e4uialent to the amount of analyte in the sample! Feferences stated that spinach is a type of e.etale that rich -ith iron aout !&m. in $00.! *or this e,pe e,peri rime ment nt// the the conc concen entr trat atio ion n of iron iron is $!%' $!%'M M in 50m9 50m9 samp sample le!! +he +he actu actual al
concentration is 1no-n -hen the diluted concentration is multiply -ith the dilution factor! +he dilution factor is crucial to .et the actual concentration of the analyte! +he error that occurs in this e,periment is -hen the dilution factor -as not recorded/ so that that the actual actual conce concentr ntrati ation on of the sample sample is un1noun1no-n! n! +he +he conce concentr ntrati ation on of cadmium in the diluted sample is $!$'M! +he safe amount of cadmium consume y human is aout lo-er than #m.G1.! Hi.her amount of cadmium in human ody can rin. to health prolem! *rom the caliration cure plotted/ the F # alues are nearly to $ for oth caliration cures! +he nearer the F # alue to $/ the strai.ht line is etter est fit ! 6hen preparin. the standard solution/ ma1e sure to use the calirated apparatus that is most important/ the pipette! Df the olume transferred is not correct/ the concentration of solution made -ill e -ron.! 6et di.estion method must e handled -ith care ecause it used the concentration solution that harmin.!
C-NC)SI-N:
+he +he conc concen entr trat atio ion n of cadm cadmiu ium m in the the spin spinac ach h sampl ample e is $!$' $!$'M M -hil -hile e the the concentration of iron the spinach sample is $!%'M!
,*6*,*NC*S:
$! ! olan/ H79C H79C Solutions Solutions 8? Standard Standard Additi Additions/ ons/ Fetriee Fetrieed d April April / #0$5/ from httpGG---!sepscience!comG+ httpGG---!sepscience!comG+ec echni4uesG9CGArticlesG#$&2GH7 hni4uesG9CGArticlesG#$&2GH79C2Solutions28?2 9C2Solutions28?2 Standard2Additions! #! *! ! Holl Holler er// ! A! S1oo S1oo./ ./ S! F! Crou Crouch ch (#00 (#00') ')// 7rin 7rinci cipl ples es of Dnst Dnstru rume ment ntal al Analysis &th ed!)/ nited States/ Broo1sGCole Cen.a.e 9earnin.! ! S! 6atson/ 6atson/ :itamins :itamins and Suppleme Supplements nts 9ifestyle 9ifestyle 3uide/ 3uide/ Fetrieed Fetrieed April April / from httpGG---!-emd!comGitamins2and2s httpGG---!-emd!comGitamins2and2supplementsGlifestyle2.uide2$ upplementsGlifestyle2.uide2$$Giron2 $Giron2 supplements!
%! S! "! Nai1/ +! +! "! 7andit/ 7andit/ 7! 7! "! "! 7atra I ! "! as/ as/ ffects ffects of 3raded 9eels 9eels of Cadmium on Spinach and Caa.e 3ro-n in an Dnceptisol/ Fetrieed April / from httpGG---!tandfonline!comGdoiGasG$ httpGG---!tandfonline!comGdoiGasG$0!$080G00$0&#%!# 0!$080G00$0&#%!#0$!'&8#&%! 0$!'&8#&%! 5! +op $0 *oods Hi.hest in Dron/ Fetrieed April / from httpGG---!healthaliciousness!co httpGG---!healthaliciousness!comGarticlesGfood2sources2of2iron!php mGarticlesGfood2sources2of2iron!php!! &! Cadmium e,posure and human health/ Fetrieed April / httpGG---!cadmium!or.Gp.Jn!phpEidJmenu;5!
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