are collected in 0.1 seconds, with a resulting sampling frequency limit
of 10 Hz, allowing constant and systematic
monitoring of samples; particularly useful for dynamic samples
- Wavelength range: 190-850nm
- Sample must be in solution
unit attached to instrument for precise temperature control
- Open sample compartment for quick sample changing, mixing, reagent addition, etc.
a tungsten lamp for visible wavelengths and a deuterium lamp for UV
the diffraction grating is opposite the sample from the light sources,
stray light entering the sample compartment is not an issue
- ChemStation software graphically displays instrument control and real-time data output; includes a biochemical analysis package for interpretation of enzyme kinetics and thermal denaturation data as well as advanced controls for more intensive method development
Agilent 8453 UV-Vis Spectrophotometer
Website: Agilent Technologies
Instantly measure sample absorbance across the complete mid-UV-visible spectrum
Typical scanning spectrophotometers give the user a choice: speed or breadth. Opting for speed, you focus on a particular wavelength of interest (e.g., 280nm for protein concentration, 600nm for cell count), blind to the rest of the spectrum and the interesting and useful data it might contain. Opting for breadth, scanning the entire spectrum can take half a minute or more, often too slow to accurately study a dynamic sample.
With its photodiode-array-based sensor system and only a single moving part, the 8453 simultaneously reads the entire available spectrum, combining speed and breadth with high accuracy and sensitivity. Not only can you look at the absorbance of your sample at standard measurement wavelengths, you can check for unexpected absorbance elsewhere along the spectrum so as to discern impurities, contaminants, and other aberrations.
NanoDrop ND-1000Website: Thermo Fisher Scientific (USER MANUAL)
FREE TO USE! For quick protein and nucleic acid concentration measurements
While not ideal for qualitative measurement, the ND-1000, with an available spectrum of 220-750nm and the ability to accurately read highly-concentrated samples (e.g., up to 100 mg/mL BSA, up to 3700 ng/uL dsDNA), is useful for assessing sample quality and estimating protein concentration on the fly. You have your data within minutes, with minimal preparation and virtually no cleanup; initialize with water, calibrate with buffer, and read your samples.
The software reports data graphically, with the entire scanned spectrum plotted, and as a convenient table, with the relevant wavelength(s) noted.