Keywords
Precision
accuracy
automatic volumetric pipettes
How to Cite
Abstract
Introduction
Automatic micropipettes are widely used in clinical biology for quantitative analyses in medical diagnostics. However, in many hospitals in developing countries, this equipment is often not verified for accuracy in collecting biological sample volumes. This oversight can result in biased diagnoses with significant public health consequences, such as misdiagnosing a healthy individual as ill, or vice versa.
Purpose
This study aimed to evaluate the performance of automatic volumetric micropipettes used in hospitals across three cities in the Democratic Republic of Congo (DRC): Bukavu, Kisangani, and Kinshasa.
Methods
Fifty micropipettes were collected from hospitals in these three major cities. All micropipettes were air-displacement type A, single-channel, with fixed and variable volumes. For each micropipette, 10 repeatable deliverable volumes were weighed. The mass of water obtained was converted to volume using the density of water at room temperature (approximately 1 g/mL at 20°C). Precision was evaluated using the coefficient of variation, while accuracy was determined by comparing the delivered volume to the nominal volume. The tolerances recommended by ISO 8655:2002 were applied in analyzing the results.
Results
The findings revealed that 12 out of 50 (24%) of the micropipettes analyzed were non-compliant. Non-compliance rates included 14% in Kinshasa and 10% in Bukavu, while all micropipettes from Kisangani were compliant.
Conclusion
This research highlights the importance of reinforcing staff skills regarding equipment performance verification. Ensuring the performance of micropipettes is crucial to the quality assurance systems in clinical biology laboratories, as it guarantees reliable medical diagnostic results and safeguards public health.
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