Asys UVM 340 Microplate Reader From Biochrom

Many biological processes, such as enzymatic activities, can be monitored following colorimetric changes of appropriate reagents. Furthermore, colored reagents can be used for other tasks, such as the calculation of the protein concentration in a solution. A very famous example is the Bradford reagent, which is based on the absorbance shift of the dye Coomassie that occurs when it binds to proteins. When a colorimetric assay is performed, the optical density is determined using a specific wavelength of light.

The Asys UVM 340 can measure the optical density and the spectral characteristics of dozens of samples simultaneously. This device contains a Fastie-Ebert monochromator that allows you to choose any wavelength from 340 to 800 nm, in 1 nm increments. The wavelength can be very easily adjusted using the software that accompanies the device.

The UVM 340 is very flexible and can measure any plate format from 12 to 384 wells. You can adjust the plate format using the device’s software and following the instructions on the manual, which can be found on the software CD. The flexibility of this instrument is due to the use of a single channel to perform the measurement. The scanning process is very fast; the time needed to measure all 96 wells of a plate is 25 sec.

Another useful feature of this device is that it allows scanning of a single well on the plate for a range of possible wavelengths between 340 and 800 nm. The software that comes with the device can be used to perform various statistical functions, such as calculation of average or median values, standard deviations, etc. Also the kinetics of a reaction can be measured. Furthermore, the software can be used to process the data, after they have been stored and create graphs that can be printed or used in presentations. The instructions on how to perform all these functions can be found in the very detailed manual accompanying the plate reader.

I use this reader daily for routine determination of protein concentration in various samples and measurement of the rate of ATP hydrolysis by enzymes. Setting up the device for simple measurements was easy and I started using it for real experiments just a few hours after it was installed in the lab. A very small drawback of this device is that the sample tray does not retract automatically after the measurement is complete, increasing the chance of it being left ejected. This can be easily overcome by placing a warning sign on the instrument, so that no user forgets to retract it manually. Also, the manual can be a little bit difficult to understand at some points, but overall, it is very detailed and helpful.

I would strongly recommend the UVM 340 for anyone that routinely needs measurements of the optical density of samples, due to its simplicity and the reproducibility of its measurements.