Description
Densitometer DEN-1B designed to measure the turbidity of cell suspensions within the range of 0.0–6.0 McFarland units (McF) (0 – 180× 10 7 cells/ml).
The instrument is capable of measuring the turbidity of suspensions over a wider range (5.0–15.0 McFarland units), but it should be borne in mind that this leads to an increase in measurement error.
A densitometer is used to determine the concentration of cells (bacterial, yeast) during fermentation, to assess the susceptibility of microorganisms to antibiotics, to identify microorganisms using various test systems, to measure absorbance at a fixed wavelength, and to quantitatively assess the concentration of coloured solutions that absorb green light.
The principle of operation of the device is based on measuring optical density, followed by the digital display of the results in McFarland units.
The instrument is calibrated by the manufacturer to work with glass test tubes with an external diameter of 16 mm and stores the calibration data. If necessary, calibration can be performed at 2–6 points within the range and between 0.0 and 6.0 McFarland units. We recommend using Biosan standards for calibration; however, other commercial or homemade standards (e.g. BaSO₄) may also be used. The device features a function to restore factory calibration.
Technical characteristics:
| Measuring range | 0.00–15.00 McF |
|---|---|
| Display resolution | 0.01 McF |
| Light source | LED |
| Wavelength (λ) | λ = 565 ±15 nm |
| Accuracy (0.0–6.0 McF) | ±3% |
| Measurement time | 1 s |
| Sample volume | at least 2 ml |
| Outer diameter of test tubes | 12 mm, 16 mm (when using the A-12 or A-16 adapter) or 18 mm (without an adapter) |
| Factory reset function | + |
| Display. | Residential complex |
| Independent power supply | 3× «AA» batteries» |
| Dimensions (L × W × H) | 165×115×75 mm |
| Weight | 0.7 kg |
| Current / power consumption | 12 V, 7 mA/0.1 W |
| External power supply unit | Input: AC 100–240 V, 50/60 Hz; output: DC 12 V |
| Standard specification | External power supply, A-16 and 3× «AA» batteries» |
