Hemoglobin determination Biotest Hemoglobin SystemAccuracy and precision

Biotest Medizintechnik GmbH

2

Products

• Cuvette– Biotest Hemoglobin

• Measuring device– Biotest Hemoglobin Tester

3

Function

• Cuvette

• Blood capillary, reagent and measuring cuvette in one.

• Biotest Hemoglobin Tester

Photometer with integrated control and digital display

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Function - Cuvette

• Chemical reaction

Free Haemoglobin

Sodium nitrite Sodium azid

Erythrocytes

Haemolysis by sodium desoxycholat

Methemo-globin

Azid-Methaemo-globin

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Function - Cuvette

• Absorbance curve

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Measurementsn = 30

Mean g/dl SD g/dl CV & Mean g/dl SD g/dl CV &Sample 1 5,50 g/dl 0,09 g/dl 1,61 % 5,46 g/dl 0,08 g/dl 1,47 %Sample 2 7,42 g/dl 0,07 g/dl 0,93 % 7,47 g/dl 0,07 g/dl 0,91 %Sample 3 7,90 g/dl 0,12 g/dl 1,46 % 7,97 g/dl 0,09 g/dl 1,12 %Sample 4 9,82 g/dl 0,06 g/dl 0,61 % 10,03 g/dl 0,12 g/dl 1,23 %Sample 5 10,13 g/dl 0,10 g/dl 1,02 % 10,05 g/dl 0,12 g/dl 1,17 %Sample 6 11,70 g/dl 0,09 g/dl 0,77 % 11,65 g/dl 0,07 g/dl 0,58 %Sample 7 11,88 g/dl 0,24 g/dl 2,04 % 11,75 g/dl 0,10 g/dl 0,81 %Sample 8 12,77 g/dl 0,08 g/dl 0,63 % 12,68 g/dl 0,10 g/dl 0,81 %Sample 9 13,48 g/dl 0,11 g/dl 0,84 % 13,47 g/dl 0,10 g/dl 0,76 %Sample 10 13,51 g/dl 0,08 g/dl 0,59 % 13,50 g/dl 0,13 g/dl 0,93 %Sample 11 13,65 g/dl 0,13 g/dl 0,94 % 13,51 g/dl 0,08 g/dl 0,60 %Sample 12 14,10 g/dl 0,21 g/dl 1,50 % 14,04 g/dl 0,18 g/dl 1,29 %Sample 13 14,39 g/dl 0,08 g/dl 0,56 % 14,41 g/dl 0,10 g/dl 0,69 %Sample 14 14,76 g/dl 0,10 g/dl 0,65 % 14,72 g/dl 0,09 g/dl 0,62 %Sample 15 14,82 g/dl 0,17 g/dl 1,15 % 14,82 g/dl 0,10 g/dl 0,69 %Sample 16 15,21 g/dl 0,10 g/dl 0,66 % 15,14 g/dl 0,14 g/dl 0,94 %Sample 17 15,59 g/dl 0,13 g/dl 0,82 % 15,66 g/dl 0,13 g/dl 0,82 %Sample 18 15,83 g/dl 0,10 g/dl 0,64 % 15,83 g/dl 0,16 g/dl 0,99 %Sample 19 18,36 g/dl 0,18 g/dl 0,95 % 18,57 g/dl 0,10 g/dl 0,54 %Sample 20 19,37 g/dl 0,18 g/dl 0,95 % 19,54 g/dl 0,11 g/dl 0,59 %Mean value 13,01 g/dl 0,12 g/dl 0,97 % 13,01 g/dl 0,11 g/dl 0,88 %

HiCN Biotest

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Measurements

Linearity and precision, n = 20 measurements by each blood sample.

y = 1,0064x - 0,0773R² = 0,9992

5,00

10,00

15,00

20,00

5,0 g/dl 10,0 g/dl 15,0 g/dl 20,0 g/dl

Mean value HiCN, i g/dl

Bio

tes

t H

em

og

lob

in S

ys

tem

, g

/dl

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MeasurementsVergleich venöses Blut

Biotest Hemoglobin Meßsystem mit HiCN-Methode

y = 0,9965x + 0,0363

R2 = 0,9981

0,00

5,00

10,00

15,00

20,00

25,00

0,00 5,00 10,00 15,00 20,00 25,00

HiCN-Methode Hb [g/dl]

Bio

tes

t S

yste

m H

b [

g/d

l]

Biotest

Linjär(Biotest)

n = 300

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Function - Tester

• Photometer; two wave lengths

• Evaluation and calculation

• Reading

Evaluation

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Self calibration • 100% green light, 100% red light and dark current• Compared to moment of calibration• If necessary automatic adjustment of LED current

Evaluation

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Absorption 256 g/L

12 bits = 4000 ”steps”

Resolution

0 = 100 % light 470 – 880 nm

Resolution

Max deviation = +/- 0,75 % or +/- 30 steps

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Calibration

Absorption 256 g/L

12 bits = 4000 ”steps”0 = 100 % light 470 – 880 nm

Two points of calibration for linearity; 80 and 220 g/L

Three control levels for linearity 120, 150, 180 g/L

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Function - Tester

• Calculation of HbE

xtin

ctio

n

500 570 600 700 800 880Wave length [nm]

Turbidity

Turbidity

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Hb

Time

0 min 1 min 2 min 3 min

Capillary blood

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Results - Introduction

• Accuracy– How close to true value is the result

• Precision– How close to each other are repeated

measurements with the same sample

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Results - Introduction

• Accuracy and precision

High accuracyLow precision

Low accuracyHigh precision

High accuracyHigh precision

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Results - Introduction• Accuracy:

– Deviation (mean) in g/L

– Preferred; deviation in %

• Precision:– Standard deviation SD

– Preferred; Coefficient of variation, CV %

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Results

Precision with control blood (n=50)

0

5

10

15

20

25

30

12,1 12,2 12,3 12,4 12,5 12,6 12,7

Result [g/dl]

Nu

mb

ers

Mean value 12,39 g/dlSD 0,084 g/dlCV 0,68 %

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Features

• Cuvette– Aimed for Hb-measurement with Biotest-Hemoglobin-Tester

and compatible instruments– High accuracy and precision– Can be used for venous, capillary and arterial blood– Developed to be price worth due to latest production and

control technique

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Features

• Tester Automatic calibration:

no calibration or test cuvette needed Cuvette holder minimizing the risk of contamination Automatic monitoring of power supply with fast loading of batteries

(1 hour loading > 40 hours of measuring) Automatic shut off with latest value saved Measures only cuvettes with properly haemolysed blood

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Summary

• High accuracy and precision• Easy and reliable system• Long time use on battery power

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Results - Introduction