The Eppendorf µCuvette G1.0 microvolume measuring cell is a high-quality cuvette made of aluminum and quartz glass. It is the perfect tool for measuring high concentrations in small volumes. With a fixed optical path length of only 1 mm, the µCuvette G1.0 features a light path that is ten times shorter than in standard cuvettes. This allows nucleic acid and protein concentrations to be measured with high reproducibility in a much higher concentration range without prior dilution. Due to the hydrophobic coating on the quartz glass only 1.5 µL nucleic acid or 3 µL protein sample are required for precise formation of the liquid column. Self-absorption of the µCuvette G1.0 is very low, meaning that the entire measuring range of the photometer can be used. Furthermore, 5 µL of sample solution can be used for specific fluorometric assays saving reagent.
In general, the lower the concentration of a sample, the longer the optical path length should be. The same physical model (Beer´s Lambert Law) claims, if the concentration of a sample is very high, the light path length being used should be shortened to ensure enough light can pass through the sample to reach the detector. Microvolume measurements with light path lengths equal or shorter than 1mm are recommended for concentrations above 25 ng/µL dsDNA. If you are not sure which cuvette is the right solution for your sample, please visit our “About Detection” overview and check with the Cuvette Navigator. Please notice that the BioSpectrometers and BioPhotometers both accommodate standard cuvettes and the µCuvette G1.0. Thus, Eppendorf provides the flexibility of choosing the optimal light path length to detect a wide variety of sample concentrations!
Determining concentration via extinction factor and light path length is commonly performed in a cuvette format. In the case of standard cuvettes, the path length is determined by the width of the cuvette because the light beam travels through the cuvette horizontally. When using the µCuvette G1.0, the distance between the upper and the lower portion of the cuvette determine the path length. Thus, the measurements and the calculations can be performed identical to those in standard cuvettes. Once set in the parameters, the software automatically utilizes the right light path length when calculating concentrations. A defined angle for opening and closing the cuvette allows for easy and reproducible handling. Furthermore, the hydrophobic surface coating on the quartz glass guarantees simple cleaning, precise sample positioning and stable formation of the liquid column.