Answer / srinivas

caffeiene having different wavelents it having 2 maximas
and 1 minima.
1st maxima is 205nm
2nd maxima is 273nm
minima is 245nm
and it is primary reference standard and also suggested in
pharmacopiea.
It is very stable, we can use a long time foranalysis
i.e. it is not degradable

Answer / raja

#It will detect the detector wawelenth at multiple
wavelenth.
#it can be more stable and this solution can be store for
long time.
#It is cheap in market and it is easily and completely
dissolved in methonol.This solvent also cheap thats why
more chemists like to use caffene for HPLC Calibration in
detector wavelenth accuracy test.

Answer / madhu

i said one my interview it is low cost,multiple wave lengths but these are not correct he said.any person know exact reason tell me.


but i think in uv spectroscopy some electronic bonding,non bonding transitions by c-n,c=c,c=n,n-o interactions.then it gives different wavelenghths with in the uv region only other compounds its not easily detectable

Answer / satish setti

1.caffine having mulltiple wavelengths 205,254,273nm.so we can use it at multiple wavelengths.
2.it is primary standard so stable un nature.
3.availability and freely soluble in methanol.
Because of above reasons caffine can be used in calibration.

Answer / madhan rahul

Caffeine is the universal primary standard and it is recamanded by pharmacopiea.

Caffeine having variable wavelengths maximum at 204 ,273 and minimum is 245 nm.
It is freely soluble in water and also stable in room temperature.
Its highly polar and elutes all C 18 columns at Retention time about 2 minutes.
In pharma maximum products are using 200 to 300 nm only so caffeine is used for detector calibration.
 

 

Answer / avadhesh sachan

caffeine is easily available in market, having very low cost, there is no need to cleaning of HPLC after calibration, its having two maxima(205 & 273 nm) and one minima 245







avadhesh sachan from Raptim Research Navi mumbai

Answer / pratik sutar

It shows multiple wavelength response like 205,245,273

Answer / shahjahan bano

caffeiene having different wavelents it having 2 maximas
and 1 minima.
1st maxima is 205nm
2nd maxima is 273nm
minima is 245nm
and it is primary reference standard and also suggested in
pharmacopiea.

Answer / ajay chansoriya

caffeine having different wavelengths,
1st maxima is 205nm
2nd maxima is 273nm
minima is 245nm
and it is primary reference standard and also suggested in
pharmacopiea.and available easily to market.
Cost is very less, and can be store for long time.

Ajay Chansoriya
Alembic Pharmaceuticals

Answer / nandkishor (dr reddys lab

because caffiene and Erbium perchlorate also, are detected
in both uv and visible range

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