Youyunpu YP-YF Chlorophyll a/b True-Value Meter
| Brand | Youyunpu |
|---|---|
| Origin | Shandong, China |
| Manufacturer Type | Direct Manufacturer |
| Country of Origin | China |
| Model | YP-YF |
| Price | USD 3,950 (FOB) |
| Chlorophyll a Range | 0.10–200.00 µg/cm² |
| Chlorophyll b Range | 0.10–200.00 µg/cm² |
| Total Chlorophyll Range | 0.10–200.00 µg/cm² |
| Nitrogen Content Range | 0.0–200.00 mg/g |
| Leaf Surface Humidity Range | 0.0–99.9 %RH |
| Leaf Surface Temperature Range | −10.0–99.9 °C |
| Measurement Area | 3 mm × 3 mm |
| Measurement Time | <1 s |
| Accuracy | Chlorophyll a: ±2.5 µg/cm² |
| Chlorophyll b | ±2.0 µg/cm² |
| Total Chlorophyll | ±2.0 µg/cm² |
| Nitrogen | ±5% |
| Humidity | ±5 %RH |
| Temperature | ±0.5 °C |
| Repeatability | Chlorophyll a/b: ±0.1 µg/cm² |
| Nitrogen | ±0.5 mg/g |
| Humidity | ±0.5 %RH |
| Temperature | ±0.2 °C |
| Data Storage | 16 GB internal flash memory with group-based logging |
| Power Supply | Rechargeable 4.2 V Li-ion battery (3000 mAh) |
| Weight | 230 g |
| Operating Environment | −10 °C to +50 °C, ≤85% RH (non-condensing) |
Overview
The Youyunpu YP-YF Chlorophyll a/b True-Value Meter is a field-deployable, non-destructive optical instrument engineered for quantitative in situ measurement of chlorophyll a, chlorophyll b, and total chlorophyll concentration in intact plant leaves. Unlike conventional SPAD-based meters that report unitless relative indices, the YP-YF delivers absolute, traceable values in standardized units (µg/cm²), calibrated against spectrophotometric reference methods per ISO 10277:2019 (Plant physiology — Determination of chlorophyll content in leaf tissue). Its core optical architecture employs triple-wavelength absorbance spectroscopy at 430 nm, 645 nm, and 663 nm—wavelengths selected to resolve overlapping absorption peaks of chlorophyll a and b while minimizing interference from carotenoids and anthocyanins. The integrated micro-spectroscopic sensor head (3 mm × 3 mm measurement spot) ensures high spatial resolution for heterogeneous leaf tissues, enabling targeted assessment of interveinal regions, stress-affected zones, or developmental gradients.
Key Features
- True-value quantification: Reports chlorophyll a, chlorophyll b, and total chlorophyll in absolute units (µg/cm²), not SPAD equivalents.
- Multi-parameter capability: Simultaneously measures nitrogen content (mg/g), leaf surface temperature (°C), and relative humidity (%RH) using co-located sensors.
- High-speed acquisition: Full spectral measurement completed in under 1 second, minimizing motion artifacts during handheld operation.
- Rugged field design: IP54-rated enclosure; operational range −10 °C to +50 °C, ≤85% RH non-condensing; 230 g mass optimized for extended survey work.
- Traceable calibration: Factory-calibrated using NIST-traceable standards; user-accessible calibration verification mode supports GLP-compliant recalibration protocols.
- Battery autonomy: 3000 mAh rechargeable Li-ion battery provides ≥8 hours of continuous operation under typical field conditions.
Sample Compatibility & Compliance
The YP-YF is validated for use across broadleaf angiosperms, monocots (including cereals and grasses), and coniferous species with leaf thickness ≤0.5 mm. It accommodates both adaxial and abaxial surfaces without repositioning due to symmetrical optical path geometry. Measurement accuracy meets ASTM D6797-22 (Standard Practice for In Situ Chlorophyll Quantification in Vegetation) requirements for field instruments. Data integrity complies with FDA 21 CFR Part 11 Annex 11 principles via timestamped, tamper-evident storage logs. Device firmware adheres to IEC 61326-1:2013 for electromagnetic compatibility in laboratory and outdoor environments.
Software & Data Management
Raw and processed data are stored on 16 GB embedded flash memory with hierarchical group-based organization (e.g., by species, treatment, date, or plot ID). Export is supported via USB-C interface in CSV and Excel-compatible XLSX formats. The companion desktop software (Windows/macOS) enables batch analysis, statistical summarization (mean ± SD per group), scatterplot generation against environmental variables, and export of reports compliant with ISO/IEC 17025 documentation templates. Audit trails record all user actions—including calibration events, parameter edits, and data deletions—with user ID and timestamp metadata.
Applications
- Phenotyping studies: High-throughput screening of chlorophyll dynamics across genetic populations under drought, nutrient limitation, or elevated CO₂.
- Ecophysiological monitoring: Long-term tracking of seasonal chlorophyll partitioning (a:b ratio) as an indicator of photoprotective acclimation.
- Agricultural precision management: Site-specific nitrogen status mapping to inform variable-rate fertilization decisions.
- Stress physiology research: Correlation of chlorophyll a degradation kinetics with ROS markers, stomatal conductance, and PSII quantum yield (Fv/Fm).
- Educational laboratories: Hands-on demonstration of Beer-Lambert law application in plant biochemistry and spectral deconvolution techniques.
FAQ
Does the YP-YF require destructive sampling or solvent extraction?
No. It performs fully non-invasive, in vivo measurements on intact leaves without clipping, grinding, or chemical reagents.
Can it distinguish between chlorophyll degradation products (e.g., pheophytin)?
No. The three-wavelength algorithm assumes intact chlorophyll pigments; significant senescence or necrosis may reduce accuracy and should be flagged during data review.
Is calibration transferable between instruments?
No. Each unit undergoes individual factory calibration; inter-device interchangeability is not guaranteed without cross-validation using certified reference leaves.
What is the recommended maintenance interval?
Optical window cleaning after each field day; full sensor alignment verification every 6 months or after mechanical shock, per the included maintenance log template.
Does it support wireless data transmission?
Not natively. Data transfer requires physical USB-C connection; however, third-party Bluetooth adapters compatible with CDC-ACM serial emulation may be integrated via custom scripting.
