JULABO PURA Series Universal Heating Bath Circulator-Free

Overview

The JULABO PURA Series represents a purpose-engineered evolution in non-circulating, precision heating baths for laboratory and quality control applications. Designed and manufactured in Germany, the PURA line operates on direct-resistance heating with PID-controlled thermal regulation—delivering stable, uniform temperature fields across the entire bath volume without internal circulation. This architecture eliminates turbulence-induced thermal gradients and avoids contamination risks associated with pump-driven systems, making it ideal for applications where sample integrity, quiet operation, and minimal maintenance are critical. The series supports continuous operation from ambient +5 °C up to 99.9 °C (with optional cooling unit and insulated lid, extending low-end capability to +18 °C), satisfying standard protocols requiring boiling-point simulation, enzyme incubation, dissolution testing, or calibration of temperature-sensitive sensors. All units comply with IEC 61010-1 safety standards and are constructed using stainless steel 304 bath vessels and reinforced polymer housings rated for long-term exposure to aqueous and mild chemical environments.

Key Features

• PID-based digital temperature control with 0.1 °C resolution and ±0.15 °C stability (measured at center point, with insulated lid installed)
• IP44-rated waterproof keypad and sealed membrane switches for splash resistance in wet lab environments
• Integrated dry-run protection circuitry that automatically deactivates heating if liquid level falls below minimum fill line
• Condensate-return bath rim design minimizes evaporation loss and prevents dripping onto benchtops during prolonged high-temperature operation
• Removable full-immersion platform (standard) enables flexible positioning of flasks, beakers, and tube racks while maintaining consistent thermal contact
• Drain valve fitted as standard on PURA 10, 14, 22, and 30 models; PURA 4 features a compact footprint optimized for benchtop space-constrained setups
• High-luminance LCD display with intuitive menu navigation and real-time status indicators (heating active, error codes, setpoint/actual deviation)

Sample Compatibility & Compliance

The PURA Series accommodates a wide range of vessel geometries—including Erlenmeyer flasks (up to 2 L), graduated cylinders, sample cuvettes, and multi-well plates—via its open-bath configuration and adjustable immersion platform. Bath opening dimensions range from 12 × 27 cm (PURA 4) to 77 × 27 cm (PURA 30), supporting both single-vessel precision work and parallel processing. Units meet EN 61326-1 (EMC) and EN 61010-1 (electrical safety) requirements. While not intrinsically compliant with GLP/GMP audit trails out-of-the-box, the system supports integration into validated workflows when paired with external data loggers meeting FDA 21 CFR Part 11 criteria. No refrigeration or external chiller is required for standard operation; optional chillers extend operational range downward but do not alter core regulatory classification.

Software & Data Management

The PURA Series operates as a standalone analog-digital hybrid instrument with no embedded firmware-based data logging or PC connectivity. Temperature setpoints and real-time readings are accessible only via the front-panel interface. For traceable recordkeeping, users may integrate third-party USB or RS232-enabled temperature loggers (e.g., Omega OM-DAQPRO-5300, Testo 176 T4) directly into the bath chamber using calibrated PT100 probes. JULABO provides detailed mounting guidelines and probe placement recommendations in the technical manual to ensure measurement repeatability within ±0.05 °C across repeated runs. All units ship with CE marking, RoHS compliance documentation, and full EU Declaration of Conformity.

Applications

• Dissolution testing per USP and Ph. Eur. 2.9.3, particularly for delayed-release formulations requiring precise 37 °C or 45 °C water baths
• Enzyme kinetics assays requiring stable sub-boiling temperatures (e.g., 55–65 °C for Taq polymerase activation)
• Calibration of liquid-in-glass thermometers, RTDs, and thermocouples against NIST-traceable references
• Sample pre-warming prior to HPLC injection or GC autosampler loading to minimize thermal shock
• Boiling-point determination and vapor-pressure studies under atmospheric conditions
• Controlled thawing of cryopreserved biological samples where mechanical agitation must be avoided

FAQ

Does the PURA Series support external temperature probe feedback control?
No. The system uses internal Pt100 sensor feedback only; external probe input is not supported.
Can the bath operate continuously at 99.9 °C for extended periods?
Yes—provided the bath is filled to the recommended minimum level and the insulated lid is installed to reduce evaporation and improve stability.
Is the stainless steel bath vessel electropolished or passivated?
All bath vessels are made from AISI 304 stainless steel with standard mill finish; electropolishing is available as a custom option upon request.
What is the maximum allowable load weight on the removable immersion platform?
The platform is rated for up to 5 kg distributed load; exceeding this may compromise thermal uniformity and mechanical stability.
Are replacement lids and drain valves available as spare parts?
Yes—JULABO offers OEM-certified insulated lids (order code: PURA-LID) and universal drain valve kits (order code: PURA-DV-KIT) with installation instructions included.