Labreador Blog

How to Calculate Km and Vmax: A Practical Enzyme Kinetics Guide

2026-08-29T00:00:00.000Z

Step-by-step guide to Michaelis-Menten kinetics: measuring initial rates, fitting Km and Vmax, why Lineweaver-Burk plots mislead, and how to report results correctly.

4PL vs 5PL for ELISA Standard Curves: Why Log-Linear Regression Fails

2026-08-25T00:00:00.000Z

ELISA standard curves are sigmoidal, not straight. Learn why four-parameter logistic (4PL) and five-parameter logistic (5PL) fitting outperforms linear or log-linear regression, and when to use each model.

How to Calculate LOD and LOQ: Formulas, Methods and Common Mistakes

2026-08-23T00:00:00.000Z

Three accepted ways to calculate the limit of detection (LOD) and limit of quantitation (LOQ) — blank SD, calibration-curve residuals, and the S/N approach — with formulas, worked numbers and reporting rules.

BCF, BAF and BSAF: How to Calculate Bioaccumulation Factors Correctly

2026-08-17T00:00:00.000Z

A practical guide to bioconcentration (BCF), bioaccumulation (BAF) and biota-sediment accumulation (BSAF) factors — formulas, units, dry vs wet weight, non-detects, and how to interpret the thresholds.

ELISA Data Analysis: A Step-by-Step Guide (2026)

2026-08-02T00:00:00.000Z

How to analyze ELISA data end to end: blank subtraction, 4PL/5PL standard curve fitting, sample interpolation, LLOQ/ULOQ limits, %CV and recovery checks.

Local-First Science: Why Your Assay Data Should Never Leave the Browser

2026-07-27T00:00:00.000Z

In 2026, cloud-hosted lab tools are quietly training on your raw data. Here is why local-first, zero-data-storage scientific software is becoming the new default — and how Labreador implements it.

Beyond R²: What to Actually Check for ELISA Method Quality

2026-07-22T00:00:00.000Z

A practical checklist of the metrics that decide whether an ELISA run is trustworthy — dynamic range, S/B, EC50 placement, CI width, recovery — and how Labreador's Method Health Panel surfaces them automatically.

Labreador v1.5 — Parallel Line Analysis, Combined Assays, and Smarter Diagnostics

2026-07-13T00:00:00.000Z

What is new in Labreador v1.5: a full Parallel Line Analysis module with relative potency, multi-run combination, Fieller CI, weighted regression, and quality-of-life polish across the app.

Parallel Line Analysis: The One Test That Separates Biosimilars From Bench Curiosities

2026-07-01T00:00:00.000Z

Why pharmacopoeias require Parallel Line Analysis for every batch of a biological product, how relative potency is actually computed, and the failure modes that quietly invalidate it.

Z'-Factor: The One Number That Tells You If Your Assay Is Worth Running

2026-06-30T00:00:00.000Z

How the Z'-factor separates publishable assays from noise, why 0.5 is the magic threshold, and how to calculate it correctly for ELISA, dose-response, and HTS screens.

IC50 vs EC50: What They Mean, How to Calculate Them, and When Each Applies

2026-06-18T00:00:00.000Z

Clear, practical guide to IC50 and EC50: definitions, when to use which, how they're calculated from a dose-response curve, and common pitfalls in fitting and reporting.

R² Is Not Enough: A 3-Tier Quality Gate for ELISA Curves

2026-05-26T00:00:00.000Z

Why a single R² value misleads on heteroscedastic ELISA curves, and how a 3-tier acceptance gate (≥0.98 / 0.95–0.98 / <0.95) protects sample interpolation.

Understanding Pollution Indices: CF, PLI and MPI Explained

2026-05-06T00:00:00.000Z

A practical guide to Contamination Factor, Pollution Load Index and Metal Pollution Index — what they measure, how they are calculated, and how to interpret them in environmental studies.

Welcome to the Labreador Blog

2026-04-21T00:00:00.000Z

An introduction to the Labreador blog — practical guides on bioassay analysis, methodology notes, and tutorials for ELISA, dose-response, kinetic, and ecotoxicology workflows.