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Questions related from Vanessa Zavatti
Catalase has intrinsic fluorescence due to its tryptophan and tyrosine residues, but I wonder if it can fluoresce at a longer wavelength, due to other residues (such as NADPH). I haven't seen...
04 April 2018 9,661 3 View
I'm working with gram negative bacteria, and I would like to know how NADPH could be excreted, or if it is something related to cells lysis. Thank you,
02 February 2018 6,295 0 View
I treated pertussis cells with ethanol and then I analyzed them in a flow cytometer after staining with cDCFDA. I would like to know why I'm getting such a strong fluorescence signal with cDCFDA...
09 September 2017 680 3 View
When I worked with DCFDA in B. pertussis, sometimes I see a yellow color after one hour of incubation (protected from light at room temperature) and sometimes not. For carboxy-DCFDA, I don't see...
05 May 2017 4,166 5 View
Could somebody please explain why I'm obtaining fluorescence signal when I combine DCFDA and H2O2 in buffer? My understanding is that DCFDA must first react with esterases to eliminate the acetyl...
02 February 2017 5,958 3 View
I understand that degradation of DNA doesn't happen so quickly as RNA. Somebody could please explain why and how this can affect flow cytometric analysis? I haven't seen any protocol for dyes that...
07 July 2016 1,975 0 View
In the literature it is reported that PFA gives poor quality profiles (high CVs) in comparison to ethanol fixation. Could somebody explain why? Thank you!
05 May 2016 2,454 4 View
What is the mechanism in which BSA does so? also, I have seen many protocols for cell fixation/permeabilization where they don't use any stabilizer and just a few where BSA is used with a buffer...
03 March 2016 8,408 6 View
The flow cytometer that I'm using just have the option of width and area for the FL2 detector (yelow/orange fluorescence), but I'm just using the green and the red detectors (FL1 and FL3). For...
03 March 2016 8,139 5 View
As I understand the events are the numbers of cells passing through the laser. So, why are there cell counting beads for quantification of cells? having the number the events is not enough? what...
01 January 2016 6,138 7 View
When I do the gating in the flow cytometer, does it just record the part that is in the gate? could I do the run without gating in the piece of equipment and then do that in the software?
01 January 2016 6,049 5 View
If I want to know the cell concentration in a sample (by absorbance), shouldn't I do first a separation by means of centrifugation to get rid of debris? in many protocols it is explained that I...
10 October 2015 8,623 19 View
I'm working with biological samples and it's very difficult to clean the cuvettes after analyze the samples in the fluorometer. I have tried using acid and I still can see some residues when I run...
06 June 2015 5,512 3 View
There are kits that can do this identification but they don't work when these co-factors are bound to enzymes. By using fluorescence, I have already identified a peak that could be one of those...
11 November 2014 1,795 5 View
I'm doing PCA to treat fluorescence spectra, and it comes out that one of the components is inversely related to protein content and the other one is proportionally related to protein content. So,...
03 March 2014 6,930 13 View
Doing fluorescence analysis, I've identified a peak related to a NADH-dehydrogenase complex, but I don't know which type of dehydrogenase is. Is there any kit I can use for this? Or any other...
11 November 2013 3,529 6 View
When analyzing free tryptophan in solution, I can see two peaks at 230nm and 280nm with the same emission ~350nm, and the peak at 230 has the highest intensity. When analyzing proteins, sometimes...
08 August 2013 126 10 View
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07 July 2013 1,657 10 View
