Why did i get other spot on tlc of phenolic acid i got from preparative tlc?

I did preparative tlc of extract and i got a band of phenolic acid (confirmed by FeCl3 1% spray reagent). The compound uv vis spectra resembles chlorogenic acid spectral, but when i did tlc of the...

30 September 2020 4,528 2 View

What is mobile phase for very polar coumarin to use for Column Chromatography?

I have a fraction that i got from Vacuum liquid chromatography with ethyl acetate:ethanol:water (100:26:1). The fraction contains of coumarin in a low Rf value (checked on tlc), so i decided to...

09 August 2020 5,317 6 View

What is the best solvent to recrystillize a polar coumarin?

I got a fraction contains of two or more compound by vacuum liquid chromatography with ethyl acetate:ethanol:water (100:26:10). The fraction was evaporate and i got chrystal mixed with brown semi...

07 March 2020 656 7 View

Waters 2707 HPLC autosampler problem?

I am using a 2707 waters HPLC device. When I try to inject a sample, it says missing plate or rack. I changed the needle and calibrated its position but I still get the same problem. I even get...

02 March 2021 1,408 1 View

Is There Any Feasible Method To Test Fluorescent Compounds Other Than Fluorescence Spectrometers ??

Is There Any Feasible Method To Test The Efficiency Of Fluorescent Compounds Other Than UV Spectrometers ? Suggestions Would Be Appreciated !

02 March 2021 5,785 3 View

How optimize the Size Exclusion Chromatography?

Hello! I'll do a size exclusion chromatography, but I only have an open column, and I'll perform the peptide extraction from yeast, using buffer lysis (sodium phosphate 50 mM/NaCl 30 mM/DNAse and...

01 March 2021 2,215 2 View

Precipitate after adding laemmli buffer to protein solution containing Potassium Acetate?

Hi, I am running a size exclusion chromatography experiment with a buffer containing Potassium Acetate as a salt. I analyse these fractions through SDS-PAGE. After boiling my SEC fractions in...

01 March 2021 2,622 3 View

Any research papers for extraction of nutrient deprivation on macroalgae? Analysed by HPLC-UV and GC/MS. Possibly from macroalgae genus Rhizoclonium?

I am doing my thesis on the nutrient deprivation on the macroalgae Rhizoclonium sp. I will be analysing the levels over a period of roughly 5 days by HPLC-UV and GC/MS. I will be using seawater as...

28 February 2021 6,477 1 View

1 nm thick MgO thin-film to be deposited on Si wafer using thermal evaporation. What will be the optimum deposition conditions?

Favourable conditions of base pressure, rate of deposition. Also, by which characterisation technique to be used to verify the thickness of the deposited film.

28 February 2021 3,640 3 View

Do you kow of any database containing data on retention time, log P and polarizability for a large number of molecules?

Hi, I am a chemistry undergraduate doing my dissertation project on HPLC. In my project, I need to predict the HPLC retention time of 20 aromatic molecules, the calibration set. To do this I will...

24 February 2021 2,602 1 View

How to prepare a thin polymer film by post-polymerization/crosslinking?

24 February 2021 2,362 5 View

Is is possible to pole with corona poling pellets of the sample material instead of thin films?

As it is highly probable that pellets will have a higher degree of air gaps and voids than thin films, is it possible to pole the samples with corona poling nevertheless? Or is there the...

24 February 2021 1,349 1 View

Any easy method of analyzing vitamin D in foods by HPLC?

Looking for method of extracting and analyzing vitamin D in foods by HPLC

24 February 2021 7,524 7 View