Fong:Spectrophotometry
From OpenWetWare
Jump to navigationJump to search
<owwmenu font="arial, helvetica, sans-serif" bold="1"
color="White" bgcolor="gray" hovercolor=#FF9933 bghovercolor="black" topfontsize="7" fontSize="7" pagewidth="750" image="Cth.JPG" lab="Fong"> Home= Lab Members=People Research=Research Internal=Internal, Protocols=Protocols, Chemical Inventory=Inventory Links=Links
</owwmenu>
Overview
Materials
- Blank
- Sample
- Fingers
- Spectrophotometer
- An expensive and fragile cuvette
Procedure
You need at least 120 μL for a good reading; dilute into water appropriately (eg. 20x dilution is 6 μL sample in 114 μL water). Also if you are reading DNA or other sample with a buffer, use a similar buffer at the same concentration in preparing your blank.
- If the spec's in lamp-off mode, press any button with your finger.
- Press "Esc" until you reach the main menu.
- Select the type of reading you are looking for.
- Enter the correct λ for your sample
- Add at least 120 μL of your prepared blank to the cuvette.
- Measure the blank and thoroughly rinse out the cuvette.
- Add at least 120 μL of your sample to the cuvette.
- Use the measured absorbance to calculate concentration.
- ?
- Profit.
Calculation
Take your absorbance at λ and multiply it by the dilution factor and the constant for the sample in question (e.g., CDNA = 50) The number obtained is the concentration in μg/mL.