Missing peak and ions of 3MCPD

I have had prepared serial dilutions of 3MCPD standard and internal standard (3MCPD-ds) for calibrating my GC-MS (Agilent ) according to EU 14573:2004. But after injection I got nothing. Non of...

03 April 2013 214 3 View

3MCPD-d5 ions missing.

I have prepared 3mcpd in 20% NaCl solution standard and 3mcpd-d5 in water as internal standard. After injection on my GC-MS 5975, the ion of 3MCPD appeared with good response but with the...

02 March 2013 1,688 11 View

HPLC failure.

Yesterday I came to my instrument ABSciex Triple Quad 5500 coupled to Agilent HPLC 1290 to initialize the profile, but it kept giving me an error message that said: "Failure to initialize binary...

01 February 2013 6,376 11 View

Dioxin analysis

There is a plan to introduce Dioxin analysis in our Lab. I need your recommendation for Which instrument we should go for.

31 December 2012 7,496 6 View

How to prepare water saturated ethyl acetate?

How to prepare water saturated ethyl acetate?

10 November 2012 2,440 2 View

Could you recommend any books about Number Theory?

Beginner level books. High level books. Analytical Number Theory. Algebraic Number Theory. Combinatorical Number Theory. Books about partitions. Books about primes.

03 March 2021 7,174 5 View

Waters 2707 HPLC autosampler problem?

I am using a 2707 waters HPLC device. When I try to inject a sample, it says missing plate or rack. I changed the needle and calibrated its position but I still get the same problem. I even get...

02 March 2021 1,408 1 View

How to compare different concentrations of nanoparticles for characterization from ICP-MS?

I took measurements of different concentrations of 15 nm and 5 nm Au nano particle solutions. I'm trying to determine which concentration I measured gives the best reading overall. I also...

02 March 2021 7,626 1 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

No title

01 March 2021 3,905 5 View

What test should I use to compare two or three means, if data is not normally distributed but sample size is > 30 in each group?

I personally feel this as a most confusing question. As per my understanding, if sample size is > 30, and sample is skewed, we can still use paramteric approach, as it will follow Z...

01 March 2021 1,587 6 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

Any research papers for extraction of nutrient deprivation on macroalgae? Analysed by HPLC-UV and GC/MS. Possibly from macroalgae genus Rhizoclonium?

I am doing my thesis on the nutrient deprivation on the macroalgae Rhizoclonium sp. I will be analysing the levels over a period of roughly 5 days by HPLC-UV and GC/MS. I will be using seawater as...

28 February 2021 6,477 1 View

I want to performe MALDI-TOF MS for bacterial identification, I would appreciate it if anyone can tell me the matrix solution preparation protocol ?

based on what I've studied on multiple papers, for peptide and protein identification Alpha-cyano-4-hydroxycinnamic acid (CHCA) is an appropriate matrix to use, I also know that the CHCA powder...

26 February 2021 6,799 3 View

How to compare 2 samples recruited with different sampling methods?

If I want to compare characteristics of 2 groups of patients, one group is recruited from a random sample of the general public while another group is from a sample with a fixed gender (male to...

26 February 2021 3,526 3 View