UV-Visible Spectrophotometer

Make: Shimadzu

Model: UV-2450

Principle

Ultraviolet-Visible spectroscopy is working based on the principle of Beer Lambert’s law. It involves, absorbance is directly proportional to intensity of the colour and thickness of the medium.

Ultraviolet light: wavelengths between 190 and 400 nm

Visible light: wavelengths between 400 and 800 nm

Sample preparation

After dissolution of sample to adjust pH is 0.7-1.3 using buffer solutions, then add 1, 5-diphenylcarbazide reagent for colour development. The intensity of the coloured sample was measured by UV-Visible spectrophotometer.

Applications

For Hexavalent chromium Analysis

Strengths

·       Accurate determination

·       UV-VIS spectrophotometer is the basic instrument

·       Determination of maximum elements in periodic table

·       Cost of maintained is low

Limitations

·       Time taken for analysis

·       At a time one parameter only it measures

·       Colouring reagents are needed

How many decimal places does the unit give for results when used for absorbance?

This unit has readout to 3 decimal places. However this unit been discontinued and has been replaced with the 83059-10, which will also provide a readout 3 decimal points.

Is it a single or dual beam?

This is a dual beam instrument

What is the minimal volume of sample to read in the spectrophotometer?

This unit uses standard 10 mm cuvettes. If very small sample size are a concern, the thermo Nano-Drop uses as little as 0.5 microliters