ATAGO RX-9000i Benchtop Digital Refractometer with High-Precision Brix, nD, and Custom Concentration Measurement

Overview

The ATAGO RX-9000i is a high-precision benchtop digital refractometer engineered for laboratory-grade measurement of refractive index (n_D), Brix (% w/w sucrose equivalent), and user-defined concentration values across diverse industrial and research applications. Unlike handheld or basic optical refractometers, the RX-9000i employs Abbe-type prism optics coupled with a high-resolution CCD photodetector array and temperature-compensated algorithm processing to deliver traceable, repeatable results under ambient conditions. Its core measurement principle relies on the critical angle method: incident light passes through a sapphire prism in contact with the sample; the resulting shadow line position at the prism–sample interface is captured optically and converted into a refractive index value with sub-micro-unit resolution. Though the RX-9000i does not integrate Peltier temperature control (unlike the RX-5000i-plus or RX-7000α models), its advanced thermal drift compensation logic—based on internal sensor feedback and real-time ambient temperature monitoring—ensures stability within ±0.000040 nD over typical lab environments (15–30°C). This makes it suitable for routine QC in regulated settings where strict procedural adherence—not active thermal regulation—is sufficient for compliance with standard test methods.

Key Features

• High-resolution digital display with 0.00001 nD resolution and 0.001% Brix readability
• Calibration verification via certified NIST-traceable reference standards (e.g., distilled water at 20°C: n_D = 1.33300)
• Multi-parameter measurement capability: refractive index (n_D), Brix (%), and up to 100 user-programmable concentration curves
• Non-destructive, single-drop sample requirement (minimum 0.3 mL) with rapid 3-second measurement cycle
• Robust sapphire prism surface (Mohs hardness 9) resistant to abrasion, corrosion, and organic solvents
• GLP-compliant data logging: time-stamped measurements stored internally (up to 1,000 records) with optional USB export
• Compliance-ready firmware supporting audit trail functionality per FDA 21 CFR Part 11 when paired with ATAGO’s optional PC software (ReflaX™)

Sample Compatibility & Compliance

The RX-9000i accommodates a broad spectrum of liquid and semi-liquid samples—including aqueous solutions, viscous syrups, emulsions, essential oils, pharmaceutical excipients, and hydrocarbon-based solvents—provided they are optically homogeneous and non-opaque. It meets key international testing standards including ISO 21745 (refractometric determination of sugar content), ASTM D1218 (refractive index of hydrocarbon liquids), USP (refractometry for pharmaceutical preparations), and JIS K 0061 (general methods for refractive index measurement). While not equipped with active temperature control, its built-in ambient temperature sensor enables manual correction using published temperature–n_D coefficients, satisfying method requirements that specify reporting at 20°C or 25°C with documented environmental conditions. For GMP-regulated environments, the instrument supports IQ/OQ documentation templates and integrates with LIMS via ASCII serial output.

Software & Data Management

The RX-9000i operates autonomously but interfaces seamlessly with ATAGO’s ReflaX™ PC software (Windows only) for enhanced traceability and workflow integration. ReflaX™ enables full data export in CSV and PDF formats, customizable report generation with company logo and QA signature fields, and secure user access control (administrator/operator roles). All measurements include embedded metadata: date/time stamp, operator ID, calibration status, ambient temperature, and measurement mode. When configured for 21 CFR Part 11 compliance, ReflaX™ provides electronic signatures, audit trails with immutable event logs (e.g., calibration edits, user logins, result deletions), and password-protected configuration changes—meeting GLP/GMP documentation rigor for pharmaceutical, food safety, and contract testing laboratories.

Applications

• Food & Beverage: Brix quantification in fruit juices, honey, jams, dairy beverages, and low-sugar formulations; batch consistency verification during production and shelf-life studies
• Pharmaceuticals: n_D-based identity testing of solvents (e.g., ethanol, propylene glycol), excipient purity assessment, and osmolality proxy for parenteral solutions
• Cosmetics: Raw material qualification (e.g., glycerin, hyaluronic acid solutions), emulsion stability monitoring, and active ingredient concentration tracking
• Chemical Manufacturing: Real-time concentration control of H₂O₂, NaOH, ethylene glycol, DMF, and cutting fluid formulations
• Petrochemicals: Hydrocarbon blend verification, lubricant base stock screening, and solvent recovery process optimization
• Agricultural Inputs: Fertilizer solution strength validation and pesticide formulation QC prior to field application

FAQ

Does the RX-9000i support automatic temperature compensation (ATC)?

No—the RX-9000i lacks integrated Peltier temperature control. It relies on ambient temperature sensing and user-applied correction factors per standard methods.
Can I measure opaque or turbid samples?

No—refractometry requires optical transparency. Suspensions, slurries, or heavily pigmented liquids must be centrifuged or filtered before analysis.
Is calibration traceable to national standards?

Yes—calibration uses ATAGO-certified reference fluids with NIST-traceable certificates of analysis (COA) included with each instrument shipment.
What is the minimum sample volume required?

0.3 mL is sufficient for reliable measurement; the sapphire prism design minimizes residual carryover between runs.
How is data security ensured during export?

USB data transfer occurs in read-only mode; ReflaX™ enforces role-based permissions and encrypted local storage for audit-ready compliance.