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Spectrophotometers
Q: What is the Beer-Lambert law?
A: The Beer-Lambert law is an equation which relates the absorption of light to the properties of the material through which the light is travelling.
The general Beer-Lambert law is usually written as:
A = E x c x L
where A is the measured absorbance, L is the path length, c is the analyte concentration and E is a constant for each species and wavelength known as the extinction coefficient.
The Beer-Lambert law is only valid at low concentration, typically <0.01M.
Q: Which model from the 63 series is right for my application?
A: The Jenway 63 series of spectrophotometers comprises of a wide range of models:-
The 6300 spectrophotometer is a non-scanning, visible wavelength instrument.
The 6305 spectrophotometer is a non-scanning, UV and visible wavelength instrument.
The 6310 spectrophotometer is a scanning, visible wavelength instrument.
The 6315 spectrophotometer is a scanning, UV and visible wavelength instrument.
The 6320D spectrophotometer is a non-scanning, visible wavelength instrument with a tall sample compartment.
In addition, Jenway offer two application specific instruments:-
The Genova spectrophotometer is a non-scanning, UV and visible wavelength instrument pre-programmed with methods and calculations for the life science industry/laboratory.
The Aquanova spectrophotometer is a non-scanning, visible wavelength instrument pre-programmed with methods and calculations for the analysis of ions in water using optional test kits.
Q: What does the Z-dimension of a spectrophotometer cell/cuvette mean?
A: Z-Dimension is defined as the distance from the bottom of the cell compartment in the instrument to the centre of the light beam. The Z-dimension or beam height in the Jenway spectrophotometers is 15mm.
Q: Why is the Z-Dimension important?
A: Each instrument manufacturer optimises the height, width, focus and placement of the light beam within the design of an instrument to ensure that it performs optimally. It is important to users when attempting to use a small sample volume, as the sample will need to be placed in line with the light path.
