Prepare standards across the intended range
Choose a concentration range that covers the expected samples, keep dilution steps explicit and prepare enough volume for replicates and handling loss.
IMMUNOASSAY · BIOANALYTICAL QC
ELISA & bioanalytical quantification hub
Move from standard preparation to 4PL or 5PL interpolation and run-level accuracy and precision checks without hiding the calibration range.
For immunoassay, biomarker and bioanalytical research teams.FROM INPUT TO INTERPRETATION
A four-step, reviewable workflow.
The sequence is a practical guide, not a substitute for a study-specific protocol.
Serial dilution calculator →
Fit the calibration model
Compare the standard observations with the fitted 4PL or 5PL curve and interpolate only where the response is supported by the validated range.
Check assay separation
Use positive and negative controls to review signal window, variability and Z′ before interpreting sample concentrations.
Review accuracy and precision
Summarize nominal-versus-measured performance by run and QC level, while preserving predefined acceptance criteria and excluded results.
INTERPRETATION GUARDRAILS
What matters beyond the formula.
Respect the reportable range
A numerical inverse can exist outside the part of the curve that has acceptable accuracy, precision and sensitivity.
Keep matrix and dilution effects visible
Standards, controls and samples need preparation conditions that support the intended interpretation.
Review the run, not one number
Curve shape, calibrator residuals, QC performance, replicate variability and dilution integrity belong together.
Common interpretation questions.
When should a 5PL model be considered?
When the calibration response is meaningfully asymmetric and the extra parameter is supported by adequate standards and predefined model-selection practice.
Can an unknown above the highest standard be reported?
Not without a validated dilution or extrapolation procedure. Dilute and remeasure when the method allows it.
Is a high R² enough for an acceptable calibration curve?
No. Review calibrator residuals, back-calculated accuracy, precision, curve coverage and run acceptance criteria.
SELECTED REFERENCES
Start with the method source.
References inform this workflow and do not imply endorsement of Tossora Lab.
Source-informed and internally checked. Independent scientific or regulatory validation is not claimed.
How we review and correct content →