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Cover Story Good Laboratory Practices

Agappe’s AGA1c reagent is the unique double reagent system which is reliable, convenient, accurate and ensures value for money. It has regular and system packs and can be performed in most of the fullyautomated or semiautomated system. method for HDL estimation is the cheapest method available, which has multiple steps in the procedure. In this method, one of the steps is centrifuging the serum-reagent mixture at 4000 RPM for a minimum of 10 minutes. Here, the timing and speed is clearly specified to make sure of getting a clear supernatant which can be used for next step. The accuracy of estimation depends on the clear supernatant and any minute particle can lead to variation in result. There are two types of common centrifuges available - one having a dial with pre-fixed speeds and the other having a variable dial. There are systems with timer for auto cut-off and display to show the speed.

Have you ever thought of the reason for variation in manual testing? One of the reasons for high CV% in manual testing is the Micropipette. Micropipettes are mechanical devices and hence are prone to wear and tear. When you closely look into the pipette manufacturers booklet, we can see that each pipette is having a tolerance range.

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TECHAGAPPE

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Now, the question is how do we validate the speed of centrifuge? Do we depend on the display value? Or the pre-fixed speed in dial? If the answer is yes, then this may lead to random errors in testing. Because of the nature of working at high speed, the wear and tear of the hardware is high and the centrifuges are vulnerable to variation in the speed upon continuous usage. It is recommended that the laboratory should perform a hardware calibration of the centrifuge periodically. For centrifuge calibration, noncontact tachometers are available in the market, which can be used for onsite calibration of the centrifuge. Make sure that the tachometer is pre-calibrated from an accredited agency for assuring traceability of onsite calibration. The laboratories can also consider opting for an accredited calibration agency, which is the easiest way.

Micropipettes Have you ever thought of the reason for variation in manual testing? One of the reasons for high CV% in manual testing is the Micropipette. Micropipettes are mechanical devices and hence are prone to wear and tear. When you closely look into the pipette manufacturers booklet, we can see that each pipette is having a tolerance range. We calibrate the Semi-automated system using a calibrator and the calibrator is taken using the micropipette. The question is: “Is the micropipette calibrated?” In majority of cases, the answer will be NO. This is one of the major factors for accuracy. The micropipette manufacturer itself

Techagappe 15th edition (April - June 2018) E-book  

Agappe Diagnostics Limited is the first Indian IVD company publishing an International Diagnostic News Journal “Techagappe” for the public t...

Techagappe 15th edition (April - June 2018) E-book  

Agappe Diagnostics Limited is the first Indian IVD company publishing an International Diagnostic News Journal “Techagappe” for the public t...

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