UV/Vis spectroscopy is routinely used for the quantification of DNA, RNA, proteins and other biological macromolecules.
Cuvette-based instruments have been used for many decades, but limited due to the large consumption of sample material.
A real breakthough in the use of the method happened when the technique could be applied to the measurement of tiny drops in microvolumes.
Titertek-Berthold, now part of Berthold Technologies, launched the first product in 2012, using a new optical technology which is patented in several countries.
Colibri Microvolume Spectrometer
The accurate quantification of DNA, RNA and proteins, and also the assessment of its purity, are of outmost importance for all kinds of downstream applications, such as qRT PCR, sequencing, microarray, western blotting and many others. But the available amount of biological samples is often very limited, especially in the case of lysates of cells grown in multiwell plates, or small tissue samples from patients or laboratory animals. Thus, UV-Vis spectrophotometers requiring the smallest volume of sample are very valuable equipment in laboratories using Molecular Biology methods. A high reproducibility, especially at low concentrations, and a wide linear range are also very desirable, in order to avoid measuring several aliquots of the same sample.
Our UV-Vis spectrophotometers have been optimized for the quantification of DNA, RNA and proteins using A260 and A280 (absorbance at 260 nm and 280 nm) and very small volumes of sample (as low as 1 µL). To assess the purity of the sample, not only the A260/A280 is automatically calculated, but also the spectrum is displayed on the screen, making it easy to notice if the purification was not good enough.
Of course, being able to measure absorbance in the visible spectrum, our spectrophotometers can also be used to quantify proteins using traditional methods, such as the Lowry, Bradford and BCA ones, or to measure a wide range of other dyes, for example, for microarray applications. Such versatile equipment is a great addition for any Life Sciences laboratory.