20 Questions 34 Answers 0 Followers
Questions related from Anette Martensson
I am working with ELISA and use HRP conjugate as detection antibody and TMB substrate. All of the protocols I have used so far the TMB substrate reaction has been stopped by adding an acidic...
12 December 2018 6,603 4 View
I am setting up a direct ELISA and have a standard curve which I fit to a 5-PL curve. When I try to calculate the concentrations of the points in the standard curve using the obtained 5-PL curve I...
03 March 2018 1,279 3 View
I want to lyze my E. coli for protein purification but I only have an ultrasound bath, not a sonicator with a probe. Does anyone have any experience of this? Any tips or protocols that can help me.
12 December 2014 1,840 9 View
I have run a non-reducing gel with samples of a few antibodies. The samples are supposed to be pure, i.e. only containing the antibody of interest. I observe some bands below the main band. Does...
08 August 2014 9,872 7 View
I am looking for a good software for fitting curves and would like to hear what software other people recommend. I want to be able to fit 4- and 5- parameter logistic curves and linear regression....
04 April 2014 6,193 45 View
I am fairly new to cell cultivation and I am wondering about the main differences between the FreeStyle 293 media from Gibco and the Pro293-DM from Lonza. As I understand it both are serum and...
05 May 2013 9,537 2 View
I am wondering what your opinion is on what cell density is optimal for expression of antibodies by transient transfection of suspension adapted HEK-293 cells in batch culture using PEI as...
02 February 2013 9,675 2 View
I want to conjugate cyclic GDP to a protein to use in immunization for antibody production. Can anyone help me with a way in which I can do this conjugation?
01 January 2013 7,364 10 View
I have a basic question I wish I knew the answer to. In several protocols for doing ELISA to study internalization of receptors or internalization of antibodies I see that they fix the cells...
12 December 2012 7,476 6 View
I am trying to concentrate a protein using Amicon Ultra centrifugal device. I have done this several times before without any problems. This time I had a larger volume of my sample so I had to...
10 October 2012 7,553 34 View
I want to set up an assay to detect internalization of an antibody in HEK cells. I want the assay to be ELISA based since I don't have access to a FACS machine or a confocal microscope. Does...
10 October 2012 8,019 21 View
I am growing hybridoma in DMEM with 5% FBS and I observe a strange thing. The cells grow very slowly and sometimes not at all, but some kind of particles are being formed in the media. It looks...
10 October 2012 8,019 4 View
I am purifying a protein from a cell supernatant with a His-trap column from GE. I get quite low yield and it seems as if the protein doesn't bind very well since I can obtain protein when...
09 September 2012 9,029 44 View
I want to purify IgY from eggs using a PEG based protocol since this is cheap and fairly simple, compared to amoniumsulphate methods. I have only found protocols where one has to centrifuge at...
08 August 2012 9,110 8 View
I have extracted proteins from an SDS-gel using the thechtip from thermofischer http://www.piercenet.com/files/TR0051-Elute-from-polyacrylamide.pdf I did however not succed to remove all the...
08 August 2012 9,002 9 View
I am trying to obtain antibodies from a hybridoma cell line called TIB-117. I am not aquainted with this cell line and do not now how much to expect, at which density I should seed them or how...
06 June 2012 9,834 5 View
I am studying the affinity of an antibody and am trying to determine EC50 without success. I get a sigmoidal curve when I plot log concentration of antibody versus responsebut when I try to...
10 October 2011 4,044 2 View
I want to express a human receptor on HEK cells. Is there anywhere, like a database or something, where I can find out if the HEK-293 cells have endogenous expression of the receptor or do I have...
08 August 2011 8,084 2 View
I am setting up an ELISA based assay for studying the affinity of IgG to Fcg receptors. I am able to measure binding of IgG if i coat with the receptor and incubate with immuno complexes of IgG in...
06 June 2011 4,091 1 View
I am trying to tranfect CHO cells with the murine FcgammaRIII. I cotransfect it with the murine gamma chain as I have read that this is required for protein expression. I have tried lipofectamine,...
06 June 2011 9,297 2 View
