Pipetting Apparatus Curve Matching for Sample Validation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing pipetting technologies struggle to accurately differentiate between accepted and rejected liquid samples, especially when dealing with heterogeneous samples like blood, due to the difficulty in setting suitable pressure tolerance ranges that can detect clots or air bubbles.
Innovation Solution
A pipetting apparatus with a computer program product that generates a simulated pressure characteristic curve based on various parameters, including fluid class, viscosity, and pipette tip geometry, allowing for iterative fitting to an actual measured curve and classification of samples based on defined threshold values.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a fixed pressure tolerance range is used for sample acceptance, then the system is simple to operate, but it cannot accurately detect clots or air bubbles in heterogeneous samples like blood
Solution Approach 1:
The system pre-stores reference pressure curves for different fluid classes (blood, aqueous, organic) under various pipetting conditions. These reference curves are generated beforehand and stored in memory, allowing the system to quickly compare actual measurements against pre-established benchmarks without requiring complex real-time analysis algorithms.
Solution Approach 2:
The system dynamically adjusts the pressure tolerance range based on the measured pressure curve characteristics. Instead of using a fixed tolerance, the system analyzes the actual pressure curve and adapts the acceptance criteria to match the specific sample properties, enabling accurate detection of anomalies like clots or air bubbles while accommodating natural variations in heterogeneous samples.
2Productivity
If the pressure tolerance range is widened to accommodate sample heterogeneity, then more samples can be accepted, but the system loses the ability to detect defects like clots or air bubbles
Solution Approach 1:
The system applies different evaluation criteria to different sections of the pressure curve. Critical sections (such as aspiration and dispensing phases) are evaluated with stricter tolerance, while less critical sections allow more variation. This localized quality control enables the system to maintain high detection sensitivity where needed while accepting natural variations elsewhere in the curve.
Solution Approach 2:
The pressure tolerance range is made dynamic rather than static. The system continuously adapts the tolerance limits based on the actual measured pressure curve and compares it against reference curves for the specific fluid class. This dynamic adjustment allows the system to maintain high productivity by accepting valid variations while still detecting true defects.
3Measurement precision
If individual evaluation of each pipetting action is implemented, then sample quality can be precisely controlled, but the processing time and computational load increase
Solution Approach 1:
The system uses reference pressure curves as templates or copies of ideal pipetting behavior for different fluid classes. Instead of developing complex evaluation algorithms from scratch, the system compares actual measurements against these pre-established reference patterns, significantly reducing computational requirements while maintaining high evaluation accuracy.
Solution Approach 2:
The system performs preliminary classification of samples into fluid classes (blood, aqueous, organic) based on pressure curve characteristics. This preliminary action allows the system to select the appropriate reference curves and evaluation criteria in advance, streamlining the subsequent detailed evaluation process and reducing overall processing time.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables the precise acceptance or rejection of pipetted samples by closely matching the simulated curve to the actual measured curve, effectively distinguishing between correct and incorrect pipetting, even with varying sample properties.
Implementation Method 1
a pump connected to the pipette tip by means of a pump conduit for generating negative pressure or positive pressure in the pipette tip
Implementation Method 2
a measurement probe functionally connected to the fluid chamber for measuring the resultant physical parameters in this fluid chamber during pipetting
Data Source
AI summary
The invention relates to a pipetting apparatus (1) having a pipette tip (2) for aspirating and dispensing liquid samples; a pump (4) for generating negative pressure or positive pressure in the pipette tip (2) that is connected to the pipette tip (2) by means of a pump conduit (3); a fluid chamber (5) defined by the pipette tip (2) and/or the pump conduit (3); a measurement probe (6) functionally connected to the fluid chamber (5) for measuring the physical parameters resulting in this fluid chamber (5) during pipetting; and a device control system (7) with a processor (8), in which an activated computer program product enables the control system (7) of the pipetting apparatus (1) to individually accept or reject pipetted liquid samples on the basis of the physical parameters measured. The pipetting apparatus (1) in accordance with the invention is characterized in that it comprises a data storage device (9) for storing an actual measured curve (41) measured during pipetting and a simulated curve (42) for such a pipetting procedure and also a computer program product that in an activated state enables the processor (8) of this pipetting apparatus (1) to generate this simulated curve (42) and approximate it to the actual measured curve (41) iteratively to create an iterative curve (43) and then matching the pipetting and/or the corresponding pipetted liquid samples to one of a plurality of decision-making criteria on the basis of sections of the measured curve (44) in the actual measured curve (41) that deviate from defined threshold values (45) in relation to the corresponding sections of the curve (46) of the iterative curve (43). A corresponding computer program product and method are included within the scope of the invention.