There are many features of a high performance UV/Vis spectrophotometer to consider before making your final purchase. Those features include analysis speed, ease of use, sample compartment size, flexibility and reliability. This guide will assist you in short-listing a few models by examining three main selection criteria: the detection wavelength range; its stray light measurement; and the instrument’s working absorbance range. UV/Vis spectrophotometers from different manufacturers come in a variety of detection wavelength ranges, spanning from 175 nm to 3,300 nm, but as a guideline you can generally group a UV/Vis spectrophotometer into one of the three ranges outlined in this guide. Check out LabWrench.com to see all the latest UV/Vis Spectrophotometers.

Consider the applications for which you will be using this spectrophotometer to determine the detection range you require, but also consider any future applications that may require a broader range. The UV/Vis range is from 190 to 900 nm. Next, choose what range of stray light performance you are comfortable with for your application and budget.

The degree to which the instrument eliminates stray light is an important specification for UV/Vis spectrophotometers and often dictates the purchase price. Defined as unwanted radiation picked up by the detector, it is measured using the ASTM method. The instrument will fall into one of two categories: A) A high-performance stray light measurement of less than or equal to 0.00003 %T @340 nm in a UV/Vis wavelength range of 190 to 900 nm or, B), stray light measurements greater than 0.00003 %T @340 nm in a UV/Vis wavelength range of 190 to 900 nm. The latest instruments that provide such measurements can be found on LabWrench’s UV-Vis Spectrophotometers Product Page.

Absorbance range is another specification to consider when evaluating whether a unit will fit your needs and it also separates higher-priced units from lower-priced equipment. Think of the sample in your application: if it is a turbid or concentrated liquid or a solid sample that is optically thick, you may require a working absorbance range between 5 A and 8 A or higher. However, for most clear liquids, measurement between 3 A and 8 A is acceptable.

The other two ranges UV-Vis Spectrophotometers fall into are the Far-UV range, which is up to 175 nm, and the NIR range, which is up to 3,300 nm. The latest models of both types can also be found on LabWrench.com.

UV/VIS Spectrophotometer Sponsors:

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From food, forensics and the environment to drug discovery, pharmaceuticals and more, Shimadzu can equip your laboratory with high-quality, rugged, cost-effective UV spectrophotometers for all of your analysis requirements. Choose from the easy-to-use UVmini-1240, the bioscience-oriented BioSpec-mini, or the UV-1800, designed to meet your compliance needs with a resolution of 1 nm, the highest in its class. Other models include the double-blazed, double monochromator UV-2550, and our research-grade UV-VIS-NIR models, which incorporate three detectors for the utmost in sensitivity. Powerful software and a full complement of accessories ensure seamless, high-performance operation for all users. Shimadzu Scientific Instruments www.ssi.shimadzu.com/UV

Thermo Scientific NanoDrop Products NanoDrop 2000/2000c and NanoDrop 8000 UV-Vis Spectrophotometers are the Gold Standard in microvolume quantitation for DNA, RNA, Protein and more. Discover for yourself why scientists are so passionate about NanoDrop products: It’s proven: • More than 25,000 instruments in labs around the world • Thousands of citations in scientific publications in virtually every field It’s simple: • Sample size 0.5 – 2.0 μL, no cuvettes • No dilutions, even for highly concentrated samples It’s versatile: • Preconfigured methods for A260, A280, labeled DNA/Protein and much more • Custom methods capability to run and share tailored applications Visit www.thermo.com/nanodrop to learn more about our free trial program.