Bhupendra Shrestha

7 Questions 27 Answers 0 Followers

Questions related from Bhupendra Shrestha

UV detector of HPLC is giving a straight line only

I have a Shimadzu LC 20AT HPLC with Prominence SPD 20A UV-VIS detector. For a few days I have been facing a problem in the UV detector. Whatever the mobile phase I use or whatever be the...

08 August 2013 3,840 6 View

Disadvantages of ion pair chromatography

I am searching for disadvantages of ion-pair chromatography. Why is this technique not more favourable with chromatographers? Is there any other alternative technique available for analyzing ionic...

01 January 2013 1,258 5 View

Tailing in HPLC peak

Hi! I am working with method development of cephalosporins. I am using buffer and methanol in the ratio of 20:80. I am also using TEA for adjusting the pH. The method worked well but towards the...

08 August 2012 3,085 31 View

Use of correction factor in assay calculation

If I am using a standard drug which is not in a salt form and the formulation is in salt form(sodium, palmitate etc.) then I have to use the correction factor for the calculation. But if both the...

08 August 2012 5,591 5 View

Why do we use column of 250x4.6mm dimension in HPLC when there are shorter columns available for method development of only a single drug or some times two?

Read 11 answers by scientists with 20 recommendations from their colleagues to the question asked by Bhupendra Shrestha on Jan 12, 2012

01 January 2012 8,268 12 View

Why should the run time of a HPLC method be around double the time of retention time of the compound?

Chromatography

01 January 2012 1,285 6 View

k value of LC method

I have seen that some of the published articles in LC which is having as less as 0.25 as k value.I have calculated the k value with the use of formula given in Snyder book by using column length...

01 January 2012 918 6 View