ELISA Scientific Calculator

A scientific ELISA analytical tool: 4PL/5PL standard curve fitting from replicate-mean calibrators, replicate CV with sample SD, dilution-corrected provisional concentration estimates, standard back-calculation review, and an optional ICH M10 LBA calibrator profile. Beta · Scientific audit in progress.

Input

Compute

Output

Interpret

Evidence

Input & Computation

Layer 1 + 2

Beta · Scientific audit in progressTeaching Mode

Curve Model

Exploratory model comparison (AICc)Weighted regression (1/Y²)

AICc comparison includes models fitted on the original response scale. Log-log regression uses a transformed response and is available as a separate manual exploratory model. AICc comparison is exploratory. The curve model, weighting scheme and transformation should be predefined during assay validation.

Standard Curve

Conc.	OD Rep 1	OD Rep 2	OD Rep 3
Standard 1 concentration	Standard 1 OD replicate 1	Standard 1 OD replicate 2	Standard 1 OD replicate 3
Standard 2 concentration	Standard 2 OD replicate 1	Standard 2 OD replicate 2	Standard 2 OD replicate 3
Standard 3 concentration	Standard 3 OD replicate 1	Standard 3 OD replicate 2	Standard 3 OD replicate 3
Standard 4 concentration	Standard 4 OD replicate 1	Standard 4 OD replicate 2	Standard 4 OD replicate 3
Standard 5 concentration	Standard 5 OD replicate 1	Standard 5 OD replicate 2	Standard 5 OD replicate 3
Standard 6 concentration	Standard 6 OD replicate 1	Standard 6 OD replicate 2	Standard 6 OD replicate 3
Standard 7 concentration	Standard 7 OD replicate 1	Standard 7 OD replicate 2	Standard 7 OD replicate 3
Standard 8 concentration	Standard 8 OD replicate 1	Standard 8 OD replicate 2	Standard 8 OD replicate 3

Samples

Label	OD Rep 1	OD Rep 2	OD Rep 3	Dil.
Sample 1 label	Sample 1 OD replicate 1	Sample 1 OD replicate 2	Sample 1 OD replicate 3	Sample 1 dilution factor
Sample 2 label	Sample 2 OD replicate 1	Sample 2 OD replicate 2	Sample 2 OD replicate 3	Sample 2 dilution factor
Sample 3 label	Sample 3 OD replicate 1	Sample 3 OD replicate 2	Sample 3 OD replicate 3	Sample 3 dilution factor
Sample 4 label	Sample 4 OD replicate 1	Sample 4 OD replicate 2	Sample 4 OD replicate 3	Sample 4 dilution factor

Plate Layout (optional)

Click to assign well types. Used for plate heatmap visualization in Analysis tab.

Evidence & References

Layer 5

Engvall E & Perlmann P (1971)

Original ELISA paper. Enzyme-linked immunosorbent assay (ELISA). Quantitative assay of immunoglobulin G. Immunochemistry 8(9):871–874.

Findlay JWA & Dillard RF (2007)

Appropriate calibration curve fitting in ligand binding assays. AAPS J 9(2):E260–E267. Establishes 4PL as the standard model for immunoassays.

ICH M10 (2022)

Bioanalytical method validation guideline. The ICH M10 LBA calibrator profile (±20% internal, ±25% lowest/highest calibrators, ≥75% of levels accepted, ≥6 levels) is applied here as an optional review, not as evidence of run validity.

Boulanger B et al. (2003)

An analysis of the ELISA and immunoassay validation parameters. J Pharm Biomed Anal 32(4–5):753–765. Defines acceptance criteria for back-calculated standards (±15%).

Broto M et al. (2019)

New perspectives in immunoassay quality control. Anal Bioanal Chem 411:7503–7514. Sigma metrics application to ELISA assay monitoring.

ECIS v2.0 beta architecture: replicate-mean calibrator points → 4PL/5PL/linear/loglog Levenberg-Marquardt fitting with convergence and domain guards → calibrator back-calculation from the same replicate means → optional ICH M10 LBA calibrator profile → replicate CV (sample SD, Grubbs outlier detection) → provisional dilution-corrected sample estimates. Status: Beta · Scientific audit in progress.

PM Lab Suite

Clinical Laboratory Intelligence Platform

Input— Structured inputs & validation

Compute— Validated formulas

Output— Critical value highlighting

Interpret— Clinical/lab relevance

Evidence— Guideline references

When to Use

Fitting 4PL/5PL ELISA standard curves from replicate-mean calibrators
Computing replicate CV with the sample standard deviation (n−1)
Back-calculating calibrator accuracy from the same replicate means used for fitting
Reviewing concentration estimates against an optional ICH M10 LBA calibrator profile
Teaching ELISA analytical concepts with viva preparation

Common Pitfalls

Treating entered calibrator endpoints as validated LLOQ/ULOQ (method-validation evidence is required)
Accepting R² alone as proof of calibration acceptability
Assuming a hook effect is excluded because no decline is visible within entered standards
Using within-run duplicate CV as a method CV in sigma metrics
Failing to correct for dilution factor in sample back-calculation

Education Modules

Structured learning

All Tools

Back to PM Lab Suite