Can someone help with Waters Xevo TQ &TQs?

I have a Xevo TQ and Xevo TQs from Waters and both the instruments are not showing any peaks for negative ionization mode. I still get peaks for positive ion mode. Has anyone ever experienced...

03 April 2018 3,189 3 View

Can anyone help with Xevo TQ MS issues?

I have multiple users running samples with anionic salts on XEVO-TQ MS. I see deposits of salts on the corona pin and the cone for direct sample analysis. Same thing happens even after SPE. Any...

08 September 2014 5,974 6 View

After a reference from Int J Body Compos Res, can any body help?

Hi, I am after the reference below, my library says it cannot obtain a copy either locally or internationally, any help appreciated! Chris Wang ZM, Heshka S, Wielopolski L, Pi-Sunyer FX, Pierson...

03 March 2021 6,193 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

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

Benefits of the 24 welled plate?

We have always used the 96 welled plate, the 48 welled plate but apparently there is much evidence on the 24 welled plate and above all its benefits.It states it is the same you would use on ELISA...

28 February 2021 1,149 1 View

Is there any published or unpublished statistics on dropout rate (Dose1 to Dose-2) for Covid-19 vaccination in India, US, UK or any other country?

Are there any published or unpublished statistics or papers on the dropout rate (Dose1 to Dose-2) for Covid-19 vaccination in India, USA, UK, or any other country where vaccination has started at...

28 February 2021 4,237 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

Standard curve shifting over time. How do I stabilise the ELISA?

24 February 2021 1,365 3 View

Steps to calculate activation energy by coats & redfern method?

I'm a chemistry student and I'm researching the kinetic degradation of mixed plastic waste. I'm having trouble calculating the activation energy by the coats & Redfern method. The data that...

24 February 2021 974 1 View

How does the injection volume impact LLOQ and ULOQ in regression analysis (LC-MSMS)?

Hello, I have run into an issue that has sparkled a debate at work: is the LLOQ/ULOQ impacted by injection volume under the following circumstances: 1) Same dilution factor of all samples 2)...

23 February 2021 9,159 3 View

Any Differences in COVID-19 vaccines?

Are there any differences (outside of the clinical trials that led to their EUA) observed in the rate of infection among those who have received the Pfizer vs Moderna vaccine since the mass...

22 February 2021 9,727 6 View