Chu Ding Technology HDP-120 Automated Petri Dish Dispensing System

Overview

The Chu Ding Technology HDP-120 Automated Petri Dish Dispensing System is an engineered solution for high-throughput, contamination-controlled preparation of microbiological culture media in regulated laboratory environments. Designed around a microcontroller-based motion control architecture, the system integrates synchronized stepper motor actuation, calibrated peristaltic fluid delivery, and programmable mechanical handling to automate the sequential stacking, positioning, dispensing, and ejection of standard 90 mm Petri dishes. Its operational principle relies on precise open-loop positional control of a rotating dish carousel and vertical z-axis lift mechanism, combined with time-synchronized peristaltic pump actuation to deliver defined volumes of molten or liquid media under laminar airflow conditions. The system is purpose-built for applications requiring strict adherence to aseptic technique—particularly in food safety testing workflows where ISO 11290-1:2017 and FDA Bacteriological Analytical Manual (BAM) Chapter 10 protocols mandate minimized operator intervention and controlled environmental exposure.

Key Features

• Peristaltic pump-driven dispensing with volumetric accuracy ≤±1.5% CV across 1–30 mL range, validated per ISO 8655-6 for positive displacement pumps
• Programmable dish capacity: user-defined batch sizes from 1 to 126 dishes; supports continuous operation with automatic end-of-batch signaling
• Integrated UV-C (254 nm) irradiation chamber ensuring ≥99.9% reduction of airborne surface contaminants during dish loading/unloading
• Controlled media exposure window: ≤10 seconds cumulative air contact per dish, compliant with CLSI M22-A3 recommendations for minimizing aerosol-mediated cross-contamination
• Motorized oscillation module (0.5–3 Hz variable frequency) ensures homogeneous media distribution prior to solidification, reducing meniscus variability and improving colony isolation efficiency
• Modular mechanical design: fully detachable turntable, dish carrier, and pump tubing assembly—compatible with standard laboratory autoclaving (121°C, 15 psi, 20 min) and chemical sterilization protocols
• Intuitive membrane keypad interface with non-volatile memory storage for ≥50 custom dispensing programs, including temperature-triggered delay logic for thermosensitive media

Sample Compatibility & Compliance

The HDP-120 accommodates all commercially available polystyrene and polypropylene Petri dishes with nominal diameters of 90 mm (±0.3 mm tolerance), including vented and non-vented configurations. It is validated for use with agar-based, broth-based, and selective enrichment media—including modified Oxford Agar (MOX), Fraser Broth, and ALOA formulations used in Listeria monocytogenes isolation per USDA-FSIS Microbiology Laboratory Guidebook (MLG) 4.05. System operation aligns with Good Laboratory Practice (GLP) documentation requirements: all dispensing events are timestamped, and manual overrides require dual-operator authentication. While not certified to IEC 61000-6-2/6-3 EMC standards out-of-box, installation in ISO Class 5 (Class 100) laminar flow hoods satisfies USP environmental control prerequisites for sterile compounding adjacent processes.

Software & Data Management

The embedded firmware supports audit-ready operation through built-in event logging: each run records dish count, dispense volume, UV activation duration, oscillation parameters, and error codes (e.g., “Pump Stall”, “Carousel Misalignment”). Logs are exportable via USB 2.0 port in CSV format for integration into LIMS platforms such as LabWare LIMS or Thermo Fisher SampleManager. Optional RS-232 serial interface enables remote start/stop commands and real-time status polling—facilitating synchronization with upstream autoclave cycles or downstream incubator loading sequences. All parameter changes trigger automatic log entries with operator ID fields, satisfying FDA 21 CFR Part 11 requirements for electronic record integrity when paired with institutional electronic signature policies.

Applications

• Routine preparation of plates for Listeria screening in food testing laboratories (AOAC 2003.07, ISO 11290-1)
• High-volume plate production for antimicrobial susceptibility testing (AST) using CLSI M02/M07-compliant inoculum densities
• Standardized agar pour plates for water quality analysis (APHA 9222 B/C) and environmental monitoring per EU GMP Annex 1
• Preparation of differential media plates (e.g., MacConkey, XLD) in clinical microbiology core labs
• Supporting GLP-compliant validation studies requiring traceable, repeatable media dispensing across multiple batches

FAQ

Does the HDP-120 support custom dish sizes beyond 90 mm?
No—the mechanical guide rails and centering mechanism are dimensionally optimized for 90 mm dishes only. Use with 100 mm or 150 mm variants is not supported and may cause misalignment or jamming.
Can the peristaltic pump handle viscous media like blood agar or chocolate agar?
Yes, provided the media is maintained at ≥45°C and pre-filtered through a 0.45 µm syringe filter; viscosity limits are ≤150 cP at dispensing temperature.
Is UV lamp calibration required, and how often?
UV intensity must be verified quarterly using a NIST-traceable radiometer; replacement lamps are rated for 5,000 hours of cumulative operation.
What maintenance intervals are recommended for the peristaltic pump tubing?
Tubing should be replaced every 200 operating hours or after 500 dispense cycles—whichever occurs first—to maintain volumetric fidelity.
Does the system include validation documentation for IQ/OQ protocols?
Factory-issued Installation Qualification (IQ) templates and Operational Qualification (OQ) test scripts are provided; Performance Qualification (PQ) must be conducted in situ using user-defined media and acceptance criteria.