Lianhua Technology LH-NO2-P11 High-Range Nitrite Nitrogen Test Strip

Overview

The Lianhua Technology LH-NO2-P11 High-Range Nitrite Nitrogen Test Strip is a field-deployable, colorimetric analytical tool engineered for rapid, on-site quantification of nitrite nitrogen (NO₂⁻–N) in environmental water samples. Based on the diazotization-coupling reaction—where nitrite ions react with sulfanilamide under acidic conditions to form a diazonium salt, subsequently coupled with N-(1-naphthyl)ethylenediamine dihydrochloride to yield a stable pink-to-magenta azo dye—the test strip delivers visual concentration estimation through standardized color comparison. Designed specifically for high-range detection (typically spanning 0.5–20 mg/L NO₂⁻–N, consistent with common regulatory screening thresholds), it supports immediate decision-making during emergency response, routine field surveys, and mobile monitoring operations where laboratory infrastructure is unavailable or impractical.

Key Features

• Rapid Visual Assessment: Delivers qualitative-to-semiquantitative results within 2–3 minutes post-sample application—no instrumentation, power source, or reagent preparation required.
• Optimized Color Development: Manufactured using precision-coated cellulose acetate substrate and stabilized chromogenic reagents to ensure uniform dye formation, minimal background interference, and high inter-batch reproducibility.
• Field-Ready Packaging: Individually sealed in aluminum-laminated pouches with desiccant, ensuring shelf life of ≥24 months when stored at 2–30 °C and protected from light and humidity.
• User-Independent Operation: Requires no calibration, training, or technical expertise; suitable for personnel across municipal utilities, environmental contractors, and first-response teams.
• Robust Environmental Tolerance: Validated for use across pH 5.0–9.0 and turbidity ≤100 NTU; compatible with surface water, groundwater, wastewater effluent, and stormwater runoff matrices.

Sample Compatibility & Compliance

The LH-NO2-P11 strip is validated for direct immersion or drop-application testing of clarified or lightly filtered aqueous samples. It complies with foundational principles outlined in ISO 6777:1984 (Water quality — Determination of nitrite — Spectrophotometric method) and aligns with EPA Method 354.1 (Nitrite by Diazotization) for qualitative screening applications. While not intended for definitive regulatory reporting per 40 CFR Part 136, it serves as a compliant pre-screening tool under EPA’s “Tiered Monitoring Strategy” for nitrite surveillance. The product is manufactured under ISO 9001-certified quality management systems and conforms to GB/T 27025–2019 (General requirements for the competence of testing and calibration laboratories) for domestic Chinese environmental monitoring standards.

Software & Data Management

As a non-instrumental, analog colorimetric method, the LH-NO2-P11 does not interface with software or digital data acquisition systems. However, result documentation follows GLP-aligned field logging practices: users record sample ID, time/date, observed color match (per included reference chart), and environmental notes in standardized field notebooks or electronic logbooks (e.g., compliant with 21 CFR Part 11 when paired with validated e-signature platforms). Optional integration with Lianhua’s proprietary LianhuaLink™ mobile app (v3.2+) enables photo-based color capture, geotagged entry, and export to CSV or PDF for audit-ready reporting—though this functionality requires separate device registration and is not embedded in the strip itself.

Applications

• Emergency response to nitrite contamination events (e.g., fertilizer spills, septic system failures, aquaculture oxygen depletion incidents)
• Routine surveillance of drinking water distribution networks and source waters for nitrite breakthrough
• Wastewater treatment plant process control—especially in denitrification basin monitoring and post-chlorination checks
• Field validation of portable photometers or lab-based ion chromatography results
• Educational demonstrations and community science initiatives requiring accessible, low-cost water quality assessment tools

FAQ

What is the detection range of the LH-NO2-P11 test strip?
The strip is calibrated for nitrite nitrogen concentrations between 0.5 mg/L and 20 mg/L, optimized for high-range field screening where elevated levels are suspected.
Can the strip be used in seawater or high-salinity samples?
Performance may be affected by chloride interference above 1000 mg/L Cl⁻; pre-dilution with deionized water and parallel blank correction are recommended for saline matrices.
Is the color chart traceable to NIST standards?
The printed reference scale is manufactured against master color standards verified via spectrophotometric calibration (CIE L*a*b* coordinates), though not directly NIST-traceable; full metrological traceability is available upon request for certified batches.
How should expired strips be disposed of?
Treat as non-hazardous solid waste per local regulations; reactive chemistry residues are negligible due to micro-dosed reagents and dry-state stabilization.
Does the strip meet ISO/IEC 17025 requirements for accredited testing?
No—it is a screening tool, not a measurement standard; accredited labs must confirm results via validated instrumental methods (e.g., IC or UV-Vis) prior to issuing certified reports.