Applitech Countleader FL 100 Fluorescent Cell Counter
| Brand | Applitech |
|---|---|
| Model | Countleader FL 100 |
| Detection Principle | Digital Imaging Cytometry with Dual-Channel Fluorescence (470/525 nm & 535/617 nm) |
| Sample Volume | 15 µL per well |
| Throughput | Up to 8 samples simultaneously |
| Analysis Modes | Brightfield, Trypan Blue Exclusion, AO/PI Dual-Fluorescence, GFP/RFP Transfection Efficiency |
| Compliance | FDA 21 CFR Part 11, GLP/GMP-ready |
| Consumable | Proprietary FL8-slide (8-well, single-use) |
| Software | Integrated image analysis platform with audit trail, electronic signature, and 3Q validation support |
| Data Output | PDF, Excel, TIFF |
| User Management | Three-tier role-based access control (Administrator, Operator, Viewer) |
Overview
The Applitech Countleader FL 100 Fluorescent Cell Counter is an automated digital imaging cytometer engineered for high-precision, high-throughput cell quantification in biopharmaceutical development, academic research, and quality control laboratories. It employs dual-channel fluorescence detection—optimized for acridine orange (AO) and propidium iodide (PI) at excitation/emission wavelengths of 470/525 nm and 535/617 nm, respectively—combined with high-resolution brightfield imaging to deliver statistically robust morphometric and viability data. Unlike flow cytometers or manual hemocytometers, the FL 100 leverages fixed-focus, motorized stage imaging across multiple fields-of-view per well, eliminating operator-dependent focusing errors and enabling reproducible cell segmentation based on intensity thresholding, size filtering, and shape descriptors (e.g., circularity, clumping ratio). Its optical architecture integrates a CMOS sensor with 5-megapixel resolution, LED-based excitation sources, and bandpass-filtered emission detection to ensure minimal spectral crosstalk and high signal-to-noise ratios—even in low-viability or heterogeneous samples such as PBMCs, CAR-T cells, or microcarrier-adapted adherent lines.
Key Features
- Simultaneous 8-sample processing using proprietary FL8-slides—each well requires only 15 µL of sample, compatible with multichannel pipettes for rapid loading
- Automated focus calibration and field stitching across 1–3 user-selectable imaging fields per well, reducing sampling bias and improving statistical confidence in concentration and viability calculations
- Integrated AO/PI nuclear staining protocol with built-in compensation for background fluorescence and debris interference—enabling accurate enumeration of nucleated cells without manual gating or parameter tuning
- Preconfigured analysis modules for Trypan Blue exclusion, AO/PI viability assessment, GFP/RFP transfection efficiency quantification, and microcarrier-derived suspension cultures (using Applitech Reagent A+B lysis system)
- FDA 21 CFR Part 11-compliant software architecture featuring electronic signatures, immutable audit trails, role-based user permissions (Administrator/Operator/Viewer), and full traceability of all analysis parameters, results, and instrument events
- Onboard validation support—including IQ/OQ/PQ documentation templates, traceable calibration beads (multiple concentrations), and instrument-specific verification reports aligned with ISO 21748 and USP <1043>
Sample Compatibility & Compliance
The Countleader FL 100 supports a broad range of mammalian cell types—including suspension lines (CHO, HEK293), primary immune cells (PBMCs, CAR-T), stem cells, and microcarrier-grown adherent cells following chemical lysis. Its AO/PI assay specifically discriminates nucleated viable (AO+/PI−) and non-viable (AO+/PI+) cells while excluding platelets, RBCs, cellular debris, and air bubbles via morphological filtering. All consumables—including FL8-slides and Reagent A+B—are manufactured under ISO 13485-certified conditions and supplied with lot-specific CoA documentation. The system meets requirements for GMP-aligned workflows per ICH Q5D and is routinely deployed in QC release testing for viral vector production, vaccine manufacturing, and ATMP process monitoring.
Software & Data Management
The embedded Countleader Analysis Suite provides a validated, standalone Windows application with intuitive workflow navigation and configurable reporting templates. Each analysis session logs metadata—including operator ID, timestamp, sample name, dilution factor, staining protocol, and imaging parameters—with automatic compensation for user-entered dilution factors during concentration calculation. Statistical outputs include total cell concentration (cells/mL), viable cell concentration, viability percentage, mean cell diameter (µm), circularity index (0–1), clumping ratio (%), and growth curve interpolation over time-series experiments. Data export supports PDF (with embedded images and histograms), Excel (tabular raw + summary data), and TIFF (uncompressed field images)—all retaining full metadata linkage. Audit trail records capture every login, parameter change, result modification, and report generation event, satisfying regulatory expectations for data integrity under ALCOA+ principles.
Applications
- Cell Line Development: High-fidelity passage tracking and seeding density optimization using Trypan Blue mode with ≥10,000-cell counts per sample
- Immunotherapy Manufacturing: CAR-T and NK cell viability assessment under AO/PI mode—resistant to red blood cell contamination and fragmentation artifacts common in leukapheresis products
- Viral Vector Production: Accurate titer estimation and harvest timing decisions via GFP/RFP fluorescence intensity quantification normalized to total cell count
- Microcarrier Bioprocessing: Seamless integration with Applitech’s Reagent A+B lysis system for quantitative recovery of detached cells without enzymatic digestion variability
- Regulatory Submission Support: Pre-built 3Q validation packages—including installation qualification protocols, operational performance tests using NIST-traceable microbeads, and performance qualification against reference methods (e.g., flow cytometry, manual counting)
FAQ
Does the Countleader FL 100 require daily calibration or routine maintenance?
No. The system uses factory-calibrated optics and solid-state illumination; no user-performed recalibration or fluidic servicing is required between runs.
Can I use third-party slides or reagents with this instrument?
Only Applitech-certified FL8-slides and AO/PI reagents are supported to ensure optical alignment, fluidic consistency, and algorithm validation integrity.
How does the FL 100 handle clumped or irregularly shaped cells?
Its adaptive segmentation engine applies morphology-aware clustering algorithms that resolve partial overlaps and classify multi-nucleated or elongated objects based on integrated fluorescence intensity and convex hull metrics.
Is remote data access or LIMS integration possible?
Yes—via secure SFTP export or optional OPC UA interface for bidirectional communication with enterprise laboratory information management systems.
What validation documentation is included with the system?
A complete 3Q package is provided: IQ checklist with equipment certification, OQ test scripts covering focus stability, channel linearity, and repeatability (n=6), and PQ protocols aligned with ASTM E2877-22 for cell counting accuracy verification.
