The basic requirement for a spectrophotometer in our lab is for quantification of nucleic acids, which we perform every other day. Like any new lab, we also had constraints on space and funds. We purchased the NanoPhotometer™ last year. Initially we were a little skeptical about buying this as our lab is in the US and Implen is based in Germany. Nevertheless, we requested a demo and upon seeing the instrument, it was love at first sight. Being affordable, we purchased the unit.
The instrument enables both ultra low and standard volume applications for concentration measurements and estimation of purity. The ultra low volume measurement is performed with the LabelGuard™ Microliter Cell that requires only 0.7µl to 5µl. Standard cuvette applications can be done with either quartz cells or plastic cuvettes. The instrument provides a full wavelength scan from190 nm to 1100 nm. The interface is easy to read and user friendly. Pre-programmed methods for nucleic acids, proteins, and cell density applications assist in easy setup. There is also an option for user-defined methods which can be saved in the instrument for future use. The standard USB interface allows direct data download to a computer via the NanoPhotometer™ software. We also have an accessory space-saving, built-in printer.
I would strongly recommend this instrument to any laboratory that is planning to buy an efficient and reliable spectrophotometer. This is mainly because of the ease in using the instrument. Now measuring DNA/RNA is as easy as weighing chemicals. With the LabelGuard™ Microliter Cell, one only has to pipette the undiluted sample to the center of measuring window, cover it with the lid and take measurements by the push of a button. Use of either the 1 or 0.2 mm lid on the LabelGuard™ Microliter Cell creates a liquid column of defined path length of 1 and 0.2 mm, respectively. This generates virtual dilution factors of 1:10 or 1:50, respectively, in comparison to a standard 1 cm cuvette measurement. This feature saves the time needed to physically dilute the sample and avoids dilution errors. The required sample volume for the 1 mm lid is 3–5 ìL and for the 0.2 mm lid, it is 0.7–4 ìL and the absorbance value limits for both lids are between 0.025 and 1.6 at 260nm. The corresponding detection range for dsDNA, for instance, will be between 15–800 ng/µL with a 1mm lid and between 100-4000ng/µL with a 0.2mm lid.
The sample then can either be retrieved for further processing or removed by wiping out the cell with Kimwipes. The only important thing is to make sure no residual fluff is left on the cell or inside the lid. Another great feature is the minimal space requirement for this instrument. It can serve as a stand alone piece with no computer necessary for its operation. The standard cuvette application is another useful feature as it can be used for measuring cell density based on turbidity. Use of low (µl) volumes for this measurement (as with the NanoDrop®) is not advisable as the low volume will not be a true representation of the culture.
Regarding its function, I have observed that measurements made with LabelGuard™ are highly reproducible. My experience is that while other spectrophotometers often do not give the same value if we measure a sample several times in a row, the NanoPhotometer™ gives the exact same value every time. What I like the best is that the blank value is always 0.000. In addition, there is no waiting time for the instrument to warm up. Compared to the NanoDrop®, this instrument provides more functions. When measuring dye incorporation, for example, the NanoDrop® gives only the concentration of the DNA and the dyes, while the NanoPhotometer™ gives the base-to-dye ratio, eliminating the need for any calculations. If you run a large number of samples, I have seen that this amazing instrument saves a lot of time because of its ease in use. The service from the company is also great.
The only drawback I have noticed is the choice of lids. If we use the wrong lid, we may get a wrong measurement. The solution for this, as suggested by Implen, is to start with the 1 mm lid and change the lid if the value exceeds the suggested absorbance range for that lid. I was informed that they are currently modifying the software to add this utility.
In general, I will say my experience with the NanoPhotometer™ UV/Vis Spectrophotometer from Implen has been very satisfying so far.