Soi Yun

14 Questions 28 Answers 0 Followers

Questions related from Soi Yun

How can i block well for ELISA?

Hi, I'm tried to ELISA with angiopoietin protein. But I found nonspecific binding of target protein. I blocked the well with blocking buffer for 2 h at RT, and incubated with biotinylated...

27 September 2023 2,022 1 View

Why the cells were dead during ExpiCHO cell transient transfection?

Hi, I transfected DNA to ExpiCHO-S cell (passage 11, Gibco, Cat# A29127) (transient transfection) with ExpiCHO expression media using ExpiFectamine™ CHO Transfection Kit (Gibco) and OptiPRO™...

14 August 2023 1,385 7 View

What is the difference between RIPA buffer and NETN buffer for cell lysis?

I'm preparing for two protein immunoblot assay from cell lysate. The reference what i referred used two lysis buffer for cell lysis. For immunoprecipitation before western blot, NETN buffer...

13 March 2023 9,716 1 View

How can i detect the phenol red in mixture solution?

Hi. I'm trying to detect the phenol red in the mixture solution by HPLC. As you know, It is using for ph indicator. The problem is.. After making phenol red solution in 50 ml conical tube, I...

14 December 2020 5,765 4 View

How to prevent protein gelation?

Hi :D I have a question. We expressed a protein from E. coli and we got purified peptide. But when we concentrate it with centrifuge filtration (like amicon), It became like a gel. So when we...

06 October 2020 3,970 2 View

How can solve the problem during Gromac calculation?

Hi :D I'm using Gromacs 5.1.5 for MD simulation. For binding energy calculation, I used g_mmpbsa (version 5.1.2) I simulated the protein for 150ns and nojump of my xtc file. Then cut last 50ns for...

26 August 2020 7,815 1 View

How can i purify my protein sample?

Hi :D I'm doing purify a small protein from E. coli. From E. coli extract supernatant, I purified my protein using IMAC purification with LC. I got a single peak at chromatogram and got the...

24 July 2020 2,704 5 View

How to concentrate peptide/protein??

Hi :D I want to ask how to concentrate peptide/protein without the filter membrane. I purified a protein (17,000 g/mol) from E. coli with IMAC (His tag purification). The concentration was very...

30 June 2020 5,167 7 View

How can I prevent protein fragmentation in solution?

Hi, all :D I'm doing short protein expression (~17 kDa, pI 9.6) from Bl21de3 with c-term His tag. I purify it by IMAC (or affintiy chromatography). When I do SDS-PAGE and WB with Anti-His Ab, I...

26 May 2020 6,928 6 View

Is it aggregation? Or Not?

Hi all. I'm doing peptide (pI 9.1, no Cystein residue) expression from E. Coli. And I purified it using IMAC with 300 mM imidazole/50 mM Na-phosphate/300 mM NaCl (the imidazole was injected with...

23 May 2020 7,482 12 View

Peptide adsorption to filter membrane? or denatured?

Hi:) I'm doing His tagged peptide expression and purification from E.coli. I expressed the peptide and checked it with WB (with Anti-His Ab). For purification, I did IMAC and got an eluate. But it...

13 March 2020 6,629 13 View

How can i block the Ni-NTA sensor chip?

Hi. I plan to analyze binding affinity with SPR (biacore). I want to use NTA sensor chip because my ligand-protein (10 kD; no Lys residue)has 6xHis tag. But the problem is that the analyte...

20 November 2019 6,813 4 View

Why i can't His tag WB band after IMAC purification?

Hi, i expressed a small peptide (~10 kD) with C-term His tag. The target peptide was expressed with low solubility. So I make it solubilized with 2 mM EDTA. I checked overexpressed SDS-PAGE band...

09 November 2019 7,439 8 View

How can i evalute the dissociation constant from SPR data?

Hi, I have a question about evaluation of dissociation constant(kd) value from SPR (Surface plasmon resonance) analysis data. The data set already fitted with Langmuir equation by Origin pro...

18 May 2016 4,934 1 View