Junkang MC-D12A Zone of Inhibition Measuring Instrument
| Brand | Junkang |
|---|---|
| Model | MC-D12A |
| Origin | Beijing, China |
| Manufacturer Type | Authorized Distributor |
| Domestic Product Classification | Yes |
| Price | USD 14,000 (FOB Beijing) |
Overview
The Junkang MC-D12A Zone of Inhibition Measuring Instrument is a dedicated digital imaging system engineered for quantitative analysis of antimicrobial susceptibility testing (AST) in pharmaceutical quality control, microbiology research, and regulatory compliance laboratories. It operates on the principle of high-contrast, calibrated digital image acquisition followed by algorithmic edge detection and geometric measurement of circular inhibition zones formed around antibiotic-impregnated discs on agar plates. Designed in accordance with CLSI M02-A13 and EUCAST guidelines, the instrument delivers traceable, operator-independent measurements of zone diameters (in mm), enabling objective interpretation against standardized breakpoints for bacterial isolates. Its optical architecture integrates a uniform LED illumination stage, a fixed-focus industrial CMOS sensor (5 MP resolution), and automated background subtraction to minimize variability from plate opacity, agar thickness, or ambient light interference.
Key Features
- Automated zone detection with sub-millimeter measurement precision (±0.2 mm repeatability under controlled lab conditions)
- Calibration traceable to NIST-traceable stage micrometers; supports daily verification via certified calibration discs
- Dual-mode operation: single-plate batch capture (up to 6 standard 90-mm Petri dishes per scan) or sequential multi-plate workflow
- Embedded grayscale thresholding and morphological filtering to distinguish true inhibition edges from diffuse or irregular halos
- Robust mechanical design with anti-vibration base and enclosed imaging chamber to ensure consistent lighting geometry
- Compliance-ready audit trail: timestamped image capture logs, user ID tagging, and immutable raw image storage (TIFF format)
Sample Compatibility & Compliance
The MC-D12A accommodates standard Mueller-Hinton agar plates (90 mm and 150 mm diameter), as well as ISO 20776-1–compliant media formulations. It supports both Kirby-Bauer disc diffusion assays and gradient strip (E-test®) interpretations when configured with optional overlay alignment tools. All measurement outputs comply with data integrity requirements of FDA 21 CFR Part 11 (when deployed with validated software configuration and access controls), GLP Annex 11, and ISO/IEC 17025 clause 7.7 (results reporting). The system does not perform microbial enumeration or identification; it is strictly a metrological tool for zone dimension quantification.
Software & Data Management
The bundled MC-Analysis v3.2 software runs on Windows 10/11 (64-bit) and provides a validated, locked-down interface for measurement execution and report generation. Each session records full metadata—including plate ID, operator, date/time, incubation duration, and medium lot number—embedded directly into the image EXIF header. Export options include CSV (for LIMS integration), PDF (with embedded images and pass/fail annotations per CLSI criteria), and XML (for automated ingestion into enterprise QC databases). Audit logs are encrypted and write-once; modification or deletion triggers system alerts and requires dual-authentication override. Software validation documentation (IQ/OQ/PQ protocols) is available upon request for GMP-regulated environments.
Applications
- Routine QC release testing of antibiotic raw materials and finished dosage forms per USP <71> and Ph. Eur. 2.6.12
- Method verification and transfer studies for AST protocols across contract testing labs
- Stability-indicating assay support: monitoring zone diameter drift during accelerated stability programs
- Training and standardization of microbiology technicians across multi-site manufacturing networks
- Regulatory submission support: generating reproducible, auditable zone measurement data for ANDA, NDA, or MA dossier packages
FAQ
Does the MC-D12A require connection to a laboratory information management system (LIMS)?
No—standalone operation is fully supported. LIMS integration is optional via HL7 or ASTM E1384-compliant CSV export.
Can it measure zones on blood agar or chocolate agar plates?
Yes, provided plates meet CLSI-defined opacity and thickness specifications; performance validation is recommended for non-MHA media.
Is firmware upgradable in the field?
Yes, via secure USB key; all updates undergo version-controlled validation and preserve existing calibration certificates.
What training and documentation are included with purchase?
Installation qualification (IQ) documentation, operator training (8 hours remote or on-site), and a complete set of SOP templates compliant with ISO 15197 and ISO/IEC 17025 are supplied.
How is measurement accuracy verified over time?
Through built-in calibration verification using NIST-traceable reference discs (included), with automatic pass/fail flagging against ±0.3 mm tolerance limits per ISO 8655-7.
