HengAo ABDS-11 Automated Biological Dilution System

Overview

The HengAo ABDS-11 Automated Biological Dilution System is an ISO/GB-compliant, aseptic-grade liquid handling platform engineered for precise, traceable, and reproducible serial dilution of microbiological samples. It operates on the principle of positive-displacement pipetting combined with programmable vortex mixing and tube-position recognition—ensuring consistent dilution accuracy across variable sample viscosities and volumes. Designed specifically for applications requiring strict contamination control—including colony-forming unit (CFU) enumeration, viability assessment, and regulatory-compliant microbial testing—the ABDS-11 integrates seamlessly into biosafety level 1–2 laboratories, laminar flow hoods, and cleanroom environments (ISO Class 5 / Class 100). Its architecture conforms to fundamental requirements of GLP (Good Laboratory Practice) and supports audit-ready workflows aligned with ISO 7218, ISO 4833-1, USP , and FDA Bacteriological Analytical Manual (BAM) guidelines.

Key Features

• Aseptic-by-design fluidic pathway: All sample-contact components—including disposable tips, silicone tubing, and dilution tubes—are autoclavable or gamma-sterilizable; no internal valves or wetted metal surfaces.
• Automated tube identification and positioning: Integrated optical sensor array detects tube presence, orientation, and rack configuration in real time—eliminating manual alignment errors.
• Configurable dilution schemes: Supports two operational modes—11-sample × 6-dilution-step or 22-sample × 3-dilution-step—each with user-defined dilution factors (e.g., 1:10, 1:100, or custom ratios).
• On-the-fly sample insertion/removal: Open-tube architecture permits continuous loading/unloading during operation without interrupting active dilution sequences.
• Self-calibrating liquid handling: Built-in gravimetric calibration routine validates aspirated/dispensed volumes prior to each run using certified reference weights—ensuring volumetric accuracy within ±1.5% CV across 100 µL–10 mL ranges.
• Integrated FFU-compatible design: Optional built-in Fan Filter Unit (FFU) delivers ISO Class 5 airflow; alternatively, the system mounts directly onto standard laminar flow workbenches (e.g., vertical/horizontal flow hoods) via modular bracketing.
• Full digital traceability: Logs operator ID, timestamp, sample ID, dilution protocol version, and error flags to internal encrypted storage—exportable as CSV or PDF for QA/QC review.

Sample Compatibility & Compliance

The ABDS-11 accommodates standard 12–15 mL conical polypropylene dilution tubes (including screw-cap and snap-cap variants), as well as 50 mL centrifuge tubes for high-volume pre-dilutions. It handles aqueous suspensions, buffered saline solutions, nutrient broths, glycerol-stabilized cultures, and low-viscosity probiotic preparations (≤10 mPa·s). The system complies with national standards GB 4789.2–2022 (Microbiological Examination of Food and Animal Feed), GB/T 26427–2010 (Probiotic Viability Testing), and JJF 1626–2017 (Calibration Specification for Automatic Liquid Handlers). Its mechanical design meets IEC 61000-6-2 (EMC immunity) and IEC 61010-1 (Safety Requirements for Electrical Equipment for Measurement, Control, and Laboratory Use).

Software & Data Management

The ABDS-11 runs on embedded Linux-based firmware with a 7-inch capacitive touchscreen interface. Protocols are created, edited, and archived via HengAo DilutionSuite™ software—compatible with Windows 10/11 and supporting .csv/.xlsx import/export. Audit trails include full electronic signatures per 21 CFR Part 11 requirements when paired with network authentication (LDAP/Active Directory). Data encryption (AES-256) and role-based access control (RBAC) ensure secure handling of sensitive QC records. Optional integration with LIMS platforms (via HL7 or RESTful API) enables automated result transfer to laboratory information management systems.

Applications

• Food safety testing: Standardized serial dilution for aerobic plate count, coliform enumeration, and pathogen enrichment (e.g., Salmonella, Listeria) per ISO 6887 and AOAC methods.
• Pharmaceutical microbiology: Sterility test sample preparation, bioburden assessment, and environmental monitoring swab eluate processing under USP and EU Annex 1.
• Probiotic product validation: Live culture quantification using MPN (Most Probable Number) and pour-plate techniques across multi-strain formulations.
• Environmental microbiology: Soil slurry dilution for heterotrophic plate count (HPC), Pseudomonas isolation, and bioaerosol analysis per ISO 14698.
• Disinfectant efficacy testing: Reproducible log-reduction dilution series for EN 13697 and EPA Guideline 91-2 compliance studies.

FAQ

Does the ABDS-11 support third-party tube formats or custom racks?
Yes—custom rack templates can be defined in DilutionSuite™ using dimension input fields and fiducial marker mapping.
Can the system perform reverse dilutions (e.g., from high-to-low concentration)?
No—it is optimized for forward serial dilution only; reverse protocols require external reconfiguration.
Is remote monitoring or cloud-based data backup available?
Local network logging is supported; cloud backup requires on-premise IT infrastructure integration (e.g., SFTP server or NAS mount).
What maintenance intervals are recommended for long-term precision?
Gravimetric calibration every 30 days; full fluidic path sterilization before each batch; annual factory recalibration recommended.
How does the system handle viscous or particulate-laden samples?
Viscosity compensation is applied algorithmically up to 10 mPa·s; samples with >5% suspended solids require pre-filtration to avoid tip clogging.