Hengmei HM-MD Ultra Micro UV-Vis Spectrophotometer

Overview

The Hengmei HM-MD Ultra Micro UV-Vis Spectrophotometer is a benchtop dual-beam spectrophotometer engineered for high-precision quantitative and qualitative analysis in routine laboratory environments. It operates on the principle of ultraviolet–visible absorption spectroscopy, measuring sample absorbance across a continuous wavelength range from 190 nm to 1100 nm. The instrument employs a Czerny-Turner monochromator equipped with a holographic blazed grating (1200 lines/mm), enabling accurate spectral separation and minimal stray light (<0.1% T). Its optical architecture supports both single-point and full-spectrum measurements, making it suitable for applications ranging from nucleic acid and protein quantification to food authenticity testing—particularly the standardized determination of hydroxy-alpha-sanshool and related unsaturated fatty acid amides in Sichuan pepper (Zanthoxylum bungeanum) and its derivatives, such as pepper oil.

Key Features

• 7-inch high-resolution (1024 × 768) capacitive touchscreen interface with intuitive icon-driven navigation—designed for rapid method setup and real-time spectral visualization.
• Dual-lamp system (deuterium and tungsten-halogen) with fully automatic lamp switching at user-defined thresholds (default: 340 nm), ensuring seamless coverage across UV and visible regions without manual intervention.
• Advanced photometric performance: baseline stability of ±0.002 Abs (500 nm, 3 min), photometric repeatability of ±0.004 Abs (0–0.5 A), and low electronic noise (≤0.15% T), supporting GLP-compliant data acquisition.
• Integrated wireless connectivity: standard Wi-Fi and Bluetooth modules enable secure cloud synchronization via YOKE@Clouddata platform, remote firmware updates, and optional Bluetooth thermal printing—eliminating dependency on local PCs for basic reporting.
• High-capacity onboard memory stores up to 2000 spectral scans and 96 user-defined calibration curves, facilitating multi-user workflows in QC laboratories with traceable method recall.
• USB host port allows direct export of CSV-formatted data to USB flash drives; exported files are natively compatible with Microsoft Excel, MATLAB, and Python-based analytical pipelines without format conversion.

Sample Compatibility & Compliance

The HM-MD accommodates standard 10-mm pathlength cuvettes (quartz for UV, optical glass for visible), with optional microvolume adapters available for ≤2 µL sample volumes. Its optical design conforms to ISO 6507-1:2018 (spectrophotometer performance verification) and supports method validation per ICH Q2(R2) guidelines when used in pharmaceutical excipient or natural product analysis. For food safety applications—including quantification of sanshool derivatives—the instrument meets the instrumental requirements outlined in GB/T 5009.199–2003 (Chinese national standard for spice analysis) and aligns with AOAC Official Method 2012.01 for colorimetric analyte detection. All photometric calibrations are traceable to NIST-certified neutral density filters and holmium oxide reference standards.

Software & Data Management

The HM-MD supports both embedded operation and PC-based control via Yokelab desktop software (optional license). Yokelab provides audit-trail-enabled data handling compliant with FDA 21 CFR Part 11 requirements, including electronic signatures, version-controlled method storage, and immutable raw-data archiving. Cloud-integrated workflows permit synchronized access to spectral libraries, collaborative calibration sharing, and automated report generation with configurable templates (PDF/CSV). Instrument logs—including lamp usage hours, wavelength calibration history, and environmental sensor readings (temperature/humidity)—are retained for internal quality audits and ISO/IEC 17025 accreditation readiness.

Applications

• Quantitative analysis of hydroxy-alpha-sanshool in Sichuan pepper extracts using validated colorimetric assays (e.g., reaction with p-dimethylaminobenzaldehyde).
• Routine QC of food-grade oils, spices, and botanical extracts where UV-Vis spectral fingerprints correlate with active compound concentration.
• Nucleic acid (A₂₆₀) and protein (A₂₈₀/A₂₆₀) quantification in molecular biology labs, supported by preloaded calculation algorithms.
• Kinetic studies of enzyme-catalyzed reactions monitored at fixed wavelengths or via time-resolved spectral scanning.
• Pharmaceutical raw material identification using USP <731> UV absorption ratio tests and limit tests for impurities.
• Environmental water analysis for nitrate, phosphate, and heavy metal complexes via derivatization-based colorimetry.

FAQ

What wavelength accuracy and reproducibility does the HM-MD achieve?
The instrument guarantees wavelength accuracy of ±1 nm and repeatability of ±0.5 nm across its full 190–1100 nm range, verified using holmium oxide and didymium reference filters per ISO 9001 calibration protocols.
Is the HM-MD compliant with regulatory data integrity requirements?
Yes—when paired with Yokelab software, it supports 21 CFR Part 11 compliance through role-based access control, electronic signatures, and immutable audit trails for all measurement events.
Can the HM-MD perform spectral scanning in kinetic mode?
Yes—it supports time-resolved spectral acquisition at user-defined intervals (100 ms–60 s), with up to 1000 sequential scans stored internally or streamed to cloud storage.
What is the minimum detectable sample volume without microvolume accessories?
With standard 1 cm pathlength cuvettes, the lower detection limit is ~50 µL for reliable absorbance measurement; optional microvolume pedestals reduce this to 0.5–2 µL.
Does the instrument support custom method development for non-standard analytes?
Yes—users can define new calibration curves, set dynamic wavelength ranges, configure multi-point kinetics, and assign custom calculation formulas directly via the touchscreen interface or Yokelab.