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QUALITY CONTROL. of. volumetric devices. M.Jabari 2005. PIPETTES. I Line. To deliver (EX). II Line. Volumetric. To contain (IN) (Wash with solution ). Pipette. Graduated (Measuring ). PRCISION AND ACCURACY. % CV must be less than 0.3 %. % Bias must be less than 0.6%.
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QUALITY CONTROL of volumetric devices M.Jabari 2005
PIPETTES I Line To deliver (EX) II Line Volumetric To contain (IN) (Wash with solution ) Pipette Graduated (Measuring )
PRCISION AND ACCURACY % CV must be less than 0.3 % % Bias must be less than 0.6% Ideal % Bias 0 – 0.6% is acceptable
QC OF PIPETTE S(x-M)2 SD = n - 1 SD % CV = X 100 Mean Expected value Observed value _ % Bias = X 100 Expected value
QC OF PIPETTE GRAVIMETRY METHOD COLORIMETRY METHOD
GRAVIMETRY METHOD • First weight a dish . • Then with a pipette that you want caliber it transfer DW into the dish and weight that . • Repeat 10 time this action and record weight . • Caculate each time pure weight of DW that transfer with pipette. • Caculate SD , %CV and % Biass .
(X –mean)2 S(x-M)2 = 0.119 Mean = 10.06 S(x-M)2 SD = = 0.16 = 0.4 n - 1 SD % CV = X 100 = 0.04 Mean Acceptable 0.04 < 0. 3 10.06 1.07 0.119
(X –mean)2 Mean of Expected weight Mean ofObserved weight _ % Bias = X 100 Mean of Expected weight _ 10 10.06 _ % Bias = = 0.006 X 100 10 Acceptable 0.006 < 0. 6 10.06 1.07 0.119
COLORIMETRY METHOD Methyl orange 492 nm Phenol red 405 nm
For 1 ml pipette : • In a ballon class A . • Prepare 0.1 gr /100 ml (stock ) . • Dilute 1 : 11 and measure absorbance . • Select 10 tube and add 10 ml DW in each tube . (for 2 ml add 20 ml DW ) • Add 1 ml stock reagent into each tube . • Measur absorbance and record it .
Absorbance of 1:11 in class A ballone is 442 (X –mean)2 Mean of Expected OD Mean ofObserved OD _ % Bias = X 100 Mean of Expected OD _ 442 435 _ % Bias = = 1.58 X 100 442 435 0 358 No acceptable 1.58 > 0.6
(X –mean)2 S(x-M)2 = 358 Mean = 435 S(x-M)2 SD = = 39 = 6.2 n - 1 SD % CV = X 100 = 1.4 Mean No acceptable 1.4 > 0.3 435 0 358
QC OF SAMPLER GRAVIMETRY METHOD COLORIMETRY METHOD
GRAVIMETRY METHOD • Each sampler shoud assese 3 – 4 time annually . • Acceptable % CV up to 3% • Acceptable % Biass up to 5%
First weight a dish . • Then with a sampler that you want caliber it transfer DW into the dish and weight that . • Repeat 10 time this action and record weight . • Caculate each time pure weight of DW that transfer with sampler . • Caculate SD , %CV and % Biass .
(X –mean)2 S(x-M)2 = 16.1 Mean = 100.7 S(x-M)2 SD = = 1.78 = 1.33 n - 1 SD % CV = X 100 = 1.3 Mean Acceptable 1.3 < 3 100.7 16.1
(X –mean)2 Mean of Expected weight Mean ofObserved weight _ % Bias = X 100 Mean of Expected weight 100 100.7 _ % Bias = = 0.7 X 100 100 Acceptable 0.7 < 5 100.7 16.1
COLORIMETRY METHOD Methyl orange 492 nm Phenol red 405 nm
ml 10-100 sampler • For 10-100 ml sampler : • In a ballon class A . • Prepare 0.1 gr /100 ml (stock ) . • Dilute 1 : 101 and measure absorbance . • Select 10 tube and add 1 ml DW in each tube . ( for 20 ml ,50ml ,100ml add 2 , 5 , 10 ml DW ) • Add 10 ml stock reagent into each tube . • Measur absorbance and record it .
Absorbance of 1:101 in class A ballone is 455 (X –mean)2 Mean of Expected OD Mean ofObserved OD _ % Bias = X 100 Mean of Expected weight _ 455 458.4 _ % Bias = = 0.74 X 100 455 458.4 0 36.4 Acceptable 0.74 < 5
(X –mean)2 S(x-M)2 = 36.4 Mean = 458.4 S(x-M)2 SD = = 4.04 = 2.01 n - 1 SD % CV = X 100 = 0.43 Mean 458.4 0 36.4 Acceptable 0.43 < 3
ml MORE THAN 100 SAMPLER • For more than 100 ml sampler : • In a ballon class A . • Dilute 1 : 11 from stock reagent .