Hello, does anyone have any experience with packing columns for nano LC? Any suggestions on the tubings and the method used for column packing?

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

How to compare different concentrations of nanoparticles for characterization from ICP-MS?

I took measurements of different concentrations of 15 nm and 5 nm Au nano particle solutions. I'm trying to determine which concentration I measured gives the best reading overall. I also...

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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...

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

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

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I want to performe MALDI-TOF MS for bacterial identification, I would appreciate it if anyone can tell me the matrix solution preparation protocol ?

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

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

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Is it efficient to do liquid biopsy to investigate the gene expressions of the tumor?

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23 February 2021 7,326 5 View

How does the injection volume impact LLOQ and ULOQ in regression analysis (LC-MSMS)?

Hello, I have run into an issue that has sparkled a debate at work: is the LLOQ/ULOQ impacted by injection volume under the following circumstances: 1) Same dilution factor of all samples 2)...

23 February 2021 9,159 3 View

David Jensen

You may want to look at this tutorial:

http://www.benchfly.com/video/96/how-to-pack-a-capillary-column/

Christof Lenz

The benchfly video is very good to start with! We pack our own columns to 50 and 75 um ID, either into Picofrit PG360-75-15-N or into Picotips 360-75-8-N without frit. We also make KSil Frit columns in case we want to run with a discrete emitter. Material is Dr Maisch C18 aq 3A, we pack from 100% MeOH with helium pressure up to 30 cm lengths.

Shikha Taneja

Thanks David and Christof.