Determination of partial specific volume?

Dear all, For some applications in AUC, we would like to correctly determine the partial specific volume of our biomolecules. We currently use Sednterp as a principal approach which diplays a...

06 July 2019 5,392 1 View

What condition should I use for analyzing intact protein on a MALDI Mass Spectrometer?

Hello, I am working on a biophysics core facility where we have developed a service to check among other things the molecular mass of the protein of interest, the presence of contaminants and...

04 May 2019 5,435 17 View

Bevacizumab intrinsic viscosity?

10 November 2018 6,284 0 View

Multiple charges in MALDI-TOF?

Hello, Do you have a robust method to get multiple charges for proteins in MALDI-TOF? I would like to improve the precision on the mass for big proteins. I work with a UltraFleXtreme from...

04 May 2018 8,361 2 View

Why DHB is a reducing agent while sDHB matrix is not a reducing agent?

Hello everyone, My question is the next : Why the DHB matrix is a reducing agent while sDHB matrix is not a reducing agent? In this article it is written that sDHB is a non reducing agent Fast...

09 October 2017 6,560 4 View

Range of second virial coefficient

Hello, I would like to work with the second virial coefficient (A2 or B22) to determine the best conditions to formulate protein buffers and also to determine the best conditions for...

07 August 2017 8,980 3 View

Preparation of MALDI TOF experiment?

Hello everyone, I am new in the field of mass spectrometry and I have some questions about the preparation of the matrix and analyte for a MALDI TOF analysis. I prepared a saturated solution of...

09 October 2016 9,567 4 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

Can two EC50 values with different hill slopes be compared?

Hello, I fit a classical dose response curve Y=Bottom + (Top-Bottom)/(1+10^((LogEC-X)*HillSlope)) to my data (not related to inhibitors etc). The model I use is purely qualitative but it fits...

23 February 2021 8,155 5 View

I have a problem with kanamycin - why the kanamycin doesn't affect?

Hi everyone, I need to expression of GFP with pET28 plasmid in E. coli BL21(DE3) plysE. Transformed cells have kanamycin and chloramphenicol resistance. Normally, only transformed cells should...

22 February 2021 4,032 4 View

Will SARS-CoV-2 Spike be broken into S1 and S2 by denaturing conditions?

Hello, I am performing a western blot of my SARS-CoV-2 Spike-pseudotyped lentiviral particles. I denature my virus by adding concentrated virus to 2X Laemmli buffer at 1:1, then boiling for...

17 February 2021 4,844 4 View

What is the best temperature to coat an ELISA plate?

Hello, I want to control the temperature of my ELISA plate during incubations to get consistent results. In general, what is the best temperature to coat the plate with antibody? I have been...

16 February 2021 2,377 7 View

Can 5-FOA Diffuse Through Agar?

I am preparing to do a gene knockout in the filamentous fungi Coccidioides posadasii targeting pyrG/URA3 so that 5-FOA can be used for selection pressure instead of traditional antibiotic...

16 February 2021 169 4 View

Is there a way to tell based on appearance which protein crystal should diffract the best?

I have had unheard of success with protein crystallography lately from a super successful protein expression and purification batch. I have attained a lately reproducible vast amount of crystals...

09 February 2021 5,155 5 View

How to measure the concentration of a labeled protein with no tryptophan or tyrosines?

Hey I'm trying to measure the concentration of a protein I've purified and then labeled with Atto 647 flourescent dye. The protein has no tryptophans or tyrosines (although does have...

04 February 2021 4,482 4 View

What are the naitve functions of bacterial NRP?

The bacterial NRPs (nonribosomal polypeptides) are famous as clinical drugs such as antibiotics, but is there other native function of these NRPs of bacteria except antimicrobial, because their...

01 February 2021 4,280 1 View

How to solve error "Cannot find position restraint file restraint.gro (option -r)." on GROMACS?

Hi, I am about to do energy minimization but the above error occurred, I checked my .mdp file and .top file but could not find the problem. TOP file ; Include forcefield parameters #include...

01 February 2021 780 3 View