The KNAUER AZURA® VWD 2.1L is a versatile variable wavelength detector designed for analytical HPLC, FPLC, and purification applications. Combining UV/VIS detection with optional conductivity, temperature, and pH monitoring, it provides exceptional flexibility for a wide range of chromatographic workflows.
The detector supports simultaneous monitoring of up to four UV/VIS wavelengths across a broad spectral range from 190 to 900 nm. When equipped with KNAUER’s patented CombiLight flow cell, it can simultaneously measure UV absorbance, conductivity, and eluent temperature. An optional pH electrode further extends functionality by enabling real-time pH monitoring during chromatographic separations.
Key Features
- Variable wavelength UV/VIS detector for analytical HPLC and FPLC
- Simultaneous monitoring of up to 4 UV/VIS wavelengths
- Broad wavelength range from 190 to 900 nm
- Optional conductivity monitoring up to 1000 mS/cm
- Integrated temperature monitoring
- Optional real-time pH measurement
- Compatible with patented KNAUER CombiLight flow cell technology
- Convertible between flow-cell and fiber-optic configurations
- Internal holmium oxide filter for wavelength verification
- Adjustable leak sensor for enhanced operational safety
- Front-access lamp and flow-cell replacement
- Comprehensive GLP functionality with component recognition
- Suitable for analytical, preparative, and purification workflows
Technical Specifications
Detection System
- Detection channels:
- 4 × UV/VIS
- 1 × Conductivity
- 1 × Temperature
- 1 × pH
- Wavelength range: 190–900 nm
- Light source:
- High-brightness deuterium lamp
- Halogen lamp
- Integrated GLP chip
- Flow cell: Not included
- Optional display: Mobile Control
UV/VIS Performance
- Spectral bandwidth: 6 nm (FWHM)
- Wavelength accuracy: ±1.5 nm
- Wavelength precision: 0.4 nm
- Baseline noise: ±7.5 µAU at 254 nm
- Baseline drift: 200 µAU/h at 254 nm
- Linearity: >2.5 AU at 274 nm
- Maximum data rate:
- 100 Hz (single UV channel)
- 5 Hz (four UV channels)
Conductivity Monitoring
- Measurement range: 0.1–1000 mS/cm
- Accuracy: ±2% or ±0.5 mS/cm (whichever is greater)
pH Monitoring
- Measurement range: pH 0–14
- Accuracy: ±0.1 pH (between pH 2–12)
Temperature Monitoring
- Measurement range: 1–99 °C
- Accuracy: ±1.5 °C (4–40 °C)
System Functions
- Internal holmium oxide filter for wavelength verification
- Adjustable leak sensor
- Automatic integration time
- User-selectable time constants:
GLP Functions
- Lamp recognition
- Operating hours tracking
- Light source lifetime monitoring
- Flow-cell recognition
- Detailed GLP reporting
Maintenance
- Front-accessible deuterium lamp
- Front-accessible halogen lamp
- Front-accessible flow cell
- Simplified service procedures
Applications
- Analytical HPLC
- FPLC systems
- Protein purification
- Biopharmaceutical analysis
- Process chromatography
- Preparative chromatography
- Method development
- Quality control laboratories
- UV/VIS monitoring of purification processes

