Qubit fluorometer: Why am I getting different dsDNA concentrations with the same sample?

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Statistician wanted for collaboration?

Statistician required for collaboration on a research project. The project sought the opinions of medical imaging professionals about providing a preliminary image evaluation to referrers....

01 May 2019 9,048 5 View

How does one compute confidence intervals for the difference between two binomial proportions in SPSS?

I have a relatively small data set of 135 subjects. These are categorized in two dichotomous variable, type of health care and sex. I can use a Fisher's Exact test to determine if sex is...

05 March 2019 3,847 5 View

Schema therapy , Personality disorders , Older adults . What more can we learn from older patients of PD BPD to enhance therapy ?

I am currently in early stages of qualitative research design in the areas of perceptions and exploration of older adults . I am looking at investigating older adults with personality disorders...

19 February 2019 7,117 5 View

Non-parametric tests: PermANOVAs, or Kruskal-Wallis test?

Hello, Because my data has non-normal distributions, I understand I need to run non-parametric tests. My data includes multiple samples from several distant collection sites. Under what...

22 January 2019 5,467 5 View

Funding is a major problem for me. Is it less costly to check for pathogens in ticks via PCR or antigen/antibody match?

I am unclear if antibody tests can be conclusive in a tick or even if it is possible to test. If so, what are the limitations once the ticks have been collected. Limits such as temporal limits,...

08 January 2019 1,642 7 View

What evalues are recommended for BLASTing fungal sequences?

Hello, I'm using the command line to NCBI BLAST fungal DNA sequences (Table-C1, https://www.ncbi.nlm.nih.gov/books/NBK279684/). The default evalue is 10.0, but one paper I'm following used...

17 November 2018 1,031 3 View

Bacteriophage CE6 wanted - can anyone help?

I have been trying to get a sample of bacteriophage CE6 (which expresses T7 polyemerase) for protein expression studies. The lysogenic form of this is the (DE3) you see in genotypes of cells used...

14 November 2018 2,954 3 View

Grouping read IDs by sample names, and sorting samples into separate fasta files?

Dear colleagues, I pooled together dozens of samples into one library, and sequenced them together. This yielded millions of reads, with the sequencer assigning each unique read-IDs. While the...

08 October 2018 5,513 4 View

What are acceptable thresholds when using BLASTn on fungal DNA sequences?

Hello, I'd like to know your opinions on identifying fungal DNA sequences using the BLASTn with regards to Max Score, Total Score, Query Cover, E-value, and Identity match %? What are common...

06 July 2018 9,896 1 View

Similarity thresholds for fungal OTUs?

Hello, I understand there's disagreement regarding the similarity threshold for fungal OTUs, be it 95%, 97%, or 90-99%. In the literature, anyone of these threshold may be cast as adequate or too...

01 June 2018 3,308 4 View

Buffer to disrupt platelet alpha granules for PF4 quantification?

Hello! I want to quantify by ELISA the secreted (from platelets poor plasma) and the non-secreted (from platelet lysate) PF4 before and after TRAP stimulation. I will use the ELISA from R&D...

03 March 2021 1,499 2 View

Buffer Exchange using column packed with sephadex G-25 effect on protein concentration?

Hello, If i am doing a buffer exchange for an antibody of 1mg/mL, does the elution lose protein in the process of buffer exchange? For example, if i flow through 500 uL of 1mg/mL sample, and...

03 March 2021 6,299 3 View

Can linear DNA be used as template for site-directed mutagenesis?

Is it possible to induce site-directed substitution mutation by quick-change method on linear dsDNA? or it has to be cloned in some vector? If yes, should it be treated with the Dpn1 enzyme...

03 March 2021 401 4 View

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...

01 March 2021 2,215 2 View

Why are my bands weird in this Agarose gel?

Can someone please give me some possible things that could go wrong? Here is my recipe: 0.5g Agarose 50 mL of TAE 1x 1 uL ethyl bromide. Gel was run at 100V for 1 hour. The buffer used is also TAE.

01 March 2021 9,952 3 View

Which fluorescent dye to use for measuring total ROS production?

Is DCFDA appropriate for measuring total ROS production, or can it only detect certain types of ROS? If I want to measure total ROS production, which dye should I use?

01 March 2021 9,447 3 View

What do I do with DLS peaks that are from the buffer?

I'm looking at the aggregation of my protein sample using DLS. Unfortunately, my buffer (20mM HEPES) also results in a set of peaks. These are at approximately 1 and 1000 d.nm. The lowest peak...

01 March 2021 9,015 2 View

Is there anyone who experienced with cytotoxic effect of Hoescht 33342 dye?

Is Hoechst toxic to cells? In general, it is known as non-toxic. I am working with dsRED MDA-MB-231 cell line. I applied it for my PDMS-based microfluidic platform, for this reason, I incubated...

26 February 2021 9,119 3 View

What is the most suitable resuspension buffer for TCA/acetone precipitated protein?

I need to extract protein from fermented carbon sources for Bradford assay. Most researchers experiencing insolubility of pellet in resuspension buffer. Please assist me to select most suitable...

26 February 2021 7,129 3 View

What urea buffer can i use for biotagged protein extraction from streptavidin beads?

Hi all, I have been doing research on biotagged LDB1 proteins in Mel cells. I purify the proteins using M280 streptavidin beads. The yield is very low so I've been trying to optimize it by...

24 February 2021 5,749 3 View

Adam B Shapiro

It is obvious that the concentrations of the two solutions should differ by precisely 5-fold. The software may take that into account when back-calculating the original concentration before dilution, but there may be some box you have to check to make that happen.

Gary Sur

You are correct. To my chagrin, there's a step where I need to add the input volume of my sample. Thanks