Labotery GST25-20 Automated Acid Evaporation System

Overview

The Labotery GST25-20 Automated Acid Evaporation System is a precision-engineered electric heating digestion instrument designed for post-microwave acid digestion sample preparation in analytical laboratories. It operates on the principle of controlled, uniform thermal evaporation—removing residual nitric, hydrochloric, or perchloric acid from digested samples while preserving analyte integrity and minimizing elemental loss or contamination. Engineered for reproducible trace-metal analysis, the system supports standardized workflows aligned with ISO 17294-2 (water analysis), EPA Method 3050B (acid digestion of sediments and soils), and USP (heavy metals testing). Its PTFE-coated aluminum heating block ensures chemical inertness during prolonged exposure to aggressive mineral acids, making it suitable for routine use in environmental monitoring, food safety testing, agricultural research, pharmaceutical QC, and geological sample preparation.

Key Features

• Fully automated operation with microprocessor-based PID temperature control, enabling precise ramp-hold programming and scheduled start/stop functionality for unattended overnight runs.
• 25-position digestion block with Φ28 × 165 mm tube compatibility—optimized for standard CEM Mars 6, Anton Paar Multiwave PRO, and Milestone ETHOS UP microwave digestion vessels.
• 3D surround heating architecture with proprietary PTFE coating on high-purity aluminum substrate, delivering exceptional thermal uniformity (±0.5 °C inter-hole variance across 25 positions at 200 °C) and resistance to corrosion from HNO₃, HCl, HF, and aqua regia.
• High-efficiency thermal insulation design reduces ambient heat emission and energy consumption by up to 30% compared to conventional open-heating blocks.
• Dual-stage overtemperature protection: independent hardware cutoff at 230 °C plus software-triggered alarm at user-defined thresholds (configurable via front-panel interface).
• Extended duty cycle capability—certified for continuous operation exceeding 48 hours under nominal load conditions, supporting high-throughput batch processing in GLP-compliant environments.

Sample Compatibility & Compliance

The GST25-20 accommodates standard digestion tubes used in accredited microwave platforms, including CEM’s 70 mL Teflon®-lined vessels, Anton Paar’s 80 mL quartz-PTFE hybrids, and Milestone’s 100 mL rotatable rotor tubes. All wet chemistry procedures performed using this system are compatible with regulatory frameworks requiring documented thermal stability, such as FDA 21 CFR Part 11 (when integrated with compliant LIMS), ISO/IEC 17025:2017 (clause 7.2.2 on equipment suitability), and EU Regulation (EC) No 882/2004 (official controls for feed and food). The unit meets CE marking requirements for electromagnetic compatibility (EN 61326-1) and low-voltage safety (EN 61010-1).

Software & Data Management

While the GST25-20 operates via an embedded LCD interface with real-time temperature display and programmable timers (1 minute to 9999 minutes), optional RS-232/USB connectivity enables integration with laboratory information management systems (LIMS) or custom SCADA environments. Audit trail functionality—including date/time stamps, setpoint logs, actual temperature profiles, and alarm events—can be exported in CSV format for internal QA review or external audit submission. When deployed within validated workflows, the system supports electronic record retention per ALCOA+ principles (Attributable, Legible, Contemporaneous, Original, Accurate, Complete, Consistent, Enduring, Available).

Applications

• Residual acid removal following microwave-assisted digestion of soil, sediment, sludge, and plant tissue prior to ICP-OES or ICP-MS analysis.
• Pre-concentration of trace elements (e.g., Pb, Cd, As, Cr) in food matrices including cereals, dairy products, and infant formula, in accordance with EN 13804 and AOAC 2013.05.
• Routine digestion endpoint control in clinical toxicology labs processing biological fluids and tissues for heavy metal screening.
• Method development support for ASTM D5681 (determination of lead in gasoline) and ISO 11885 (water quality—determination of selected elements by ICP-AES).
• QC/QA verification of digestion completeness in contract testing laboratories accredited to ISO/IEC 17025.

FAQ

What types of digestion vessels are compatible with the GST25-20?

Standard 25–100 mL microwave digestion tubes with outer diameters ≤28 mm and heights ≤165 mm—including CEM Mars 6, Anton Paar Multiwave PRO, and Milestone ETHOS UP configurations.
Does the system support GLP-compliant data logging?

Yes—when connected to a validated external data acquisition system, full temperature history and operational events can be recorded and archived with time-stamped electronic signatures.
Is the heating surface resistant to hydrofluoric acid (HF)?

The PTFE coating provides robust resistance to HF up to 20% concentration at temperatures ≤180 °C; however, extended exposure above 190 °C requires evaluation against specific method validation protocols.
Can the GST25-20 be used for open-vessel hotplate digestion without microwave pretreatment?

It is not designed for primary digestion; its thermal profile and safety features are optimized exclusively for post-digestion acid evaporation, not for direct acid reflux or boiling applications.
What maintenance is required to ensure long-term temperature accuracy?

Annual calibration against NIST-traceable reference thermometers is recommended; cleaning with deionized water and mild non-ionic detergent preserves PTFE integrity and avoids thermal drift.