Helmi Y. Alfarra

9 Questions 40 Answers 0 Followers

Questions related from Helmi Y. Alfarra

Melting curve! What the factors that may affect on melting curve?

Hello every body. Using (SensiFast Sybr No-ROX one step kit) from Bioline, I did qPCR experiment used one -same- sample with 3 different concentrations of RNA and two different reference genes....

08 August 2016 2,389 6 View

RNA integrity?

I isolated total RNA from cancer cell lines using Trizol method.I wanted to test the integrity using bleach gel. as in the attached image the results were not cheerful to me. Can you please...

08 August 2016 9,692 7 View

Folate receptor Positive or Negative ?

Our lab have received cell lines panel. I would like to know which one in the panel is FR+ and which one is FR- ? Can any one hint me please? Thanks

06 June 2016 8,373 3 View

Is it acceptable to do wounds healing experiments on cancer cell line?

I have met some one told me that he did some experiments on wounds healing using cancer cell line instead of normal cell line. I it applicable to do that and to publish the results?

11 November 2013 4,469 11 View

Discussion case ! Different Rf on TLC with the same Rt on HPLC ? is it one compound or two compounds ?

Two compounds have been isolated from the same fraction of a plant. On TLC they showed to have different Rf. For the physical characteristics, one of them is close to being crystal-like, while the...

05 May 2013 9,443 5 View

How to check Asiaticoside by TLC ?

I have a standard of Asiaticoside 5mg/10ml methanol. I need to check it on TLC. I have used mobile phase chloroform/glacial acetic acid/ methanol/ water 60/32/12/8 and 100/40/16/8 and also I used...

02 February 2013 2,532 12 View

Confused about results of thin layer chromatography (TLC).

I have these results of TLC, I am not sure why this happens or whether the products are the same or not? Please see the picture attached bellow. This TLC was stained by vanilin and this is the...

02 February 2013 7,551 22 View

Can I use GC MS to analyse Asiaticoside? What is the best condition ?

I am working on isolation of Asiaticoside (molecular weight is 959.12) from the Centella asiatica plant. I got methanolic extract after applying the grounded leaves to Soxhelt, then I have applied...

01 January 2013 8,355 5 View

How to check if crystals are organic or inorganic compounds?

I have some crystals with different shapes and some are cube like. I have run a methanolic extract of Centella asiatica in a silica column and one of the fractions, after a long time, showed some...

01 January 2013 9,267 50 View