FICT Technology¶
This section explains the science behind Fluorescence Immunochromatographic Technology (FICT) — the detection principle that powers the Migibio FIA680/FIA880 analyzers and their quantitative test reagents.
FICT is the technology answer to a specific problem: traditional lateral-flow (colloidal-gold) strips are qualitative and operator-dependent, while laboratory immunoassays (ELISA) are quantitative but slow and lab-bound. FICT delivers quantitative, instrument-read results in minutes at the point of care.
Core Concepts¶
| Concept | Explanation |
|---|---|
| Immunochromatography | Analyte migrates along a membrane via capillary action and is captured by immobilized antibodies |
| Fluorescence labeling | The detection antibody carries a fluorophore (e.g., europium chelate) instead of gold nanoparticles |
| Instrument readout | A dedicated fluorometer excites the fluorophore and measures emitted light intensity |
| Quantitation | Emission intensity is converted to concentration via a pre-calibrated standard curve |
Why Fluorescence Enables Quantitation¶
The key difference from colloidal gold is the nature of the signal:
| Factor | Colloidal Gold | Fluorescence (FICT) |
|---|---|---|
| Signal type | Absorbance (dense color) | Emission (light) |
| Readout | Visual (human eye) | Instrument (photodetector) |
| Detection limit | ~1 ng/ml | 0.01–0.1 ng/ml (pg/ml) |
| Dynamic range | 1–2 logs | 3–4 logs |
| Quantitation | No (line presence only) | Yes (concentration) |
Because fluorescence intensity is linearly proportional to analyte concentration over a wide range and is read by an instrument rather than judged by eye, FICT achieves true quantitation — the property that separates it from qualitative strips.
Documented Resources¶
- FICT Technical White Paper — the full deep-dive: detection principle, instrumentation, performance, limitations.
- Comparative Studies — FICT head-to-head vs ELISA, PCR, and colloidal gold.
Platform Instrumentation¶
FICT requires a dedicated fluorometer. The Migibio platform provides two:
| Parameter | FIA680 | FIA880 |
|---|---|---|
| Channels | Single | Six |
| Throughput | 1 test/run | Up to 6 tests/run |
| Calibration | Pre-loaded standard curve | Cloud standard-curve sync |
See Analyzer Technology in the knowledge base for operation and maintenance.
FAQ¶
How is FICT different from a qualitative strip? A qualitative strip shows a line that a human reads as present/absent. FICT measures the intensity of a fluorescent signal with an instrument and converts it to a numerical concentration — enabling quantitative results.
Does FICT require special sample preparation? No. Serum, plasma, or whole blood is applied directly to the cartridge; the analyzer handles excitation, detection, and curve fit.
Why does FICT need a dedicated instrument? The fluorophore must be excited at a specific wavelength and its emission measured precisely — a task only a calibrated fluorometer can perform. The analyzer also stores pre-calibrated standard curves, removing inter-operator variability.
For structured performance data, see the Data Hub.
Authored by: Migibio Clinical & Scientific Affairs, Guangzhou Magic Biotech Co., Ltd.
Reviewed by: Migibio R&D Quality Committee
Last updated: 2026-08-13
Disclosure: Migibio (Guangzhou Magic Biotech Co., Ltd.) is the manufacturer of the FIA680/FIA880 analyzers and FICT reagents referenced in this content. See our Editorial & Review Policy.