Can you help me with pharmacopoeia procedure 3.2.1 on arsenic determination?

Hi to all I am writing you in order to get more information about the procedure 3.2.1 on Arsenic determination in glass containers for pharmaceutical use. In the monograph, at the paragraph...

05 June 2018 1,229 3 View

How do you overcome the following issues with S and Os ICP-OES?

hi to all, i'm experiencing several issues with detection of elements such as sulfur and osmium at icp-oes. in particular, i work with an Agilent ICP, and at each analysis, i have to analyse these...

08 September 2017 5,321 3 View

No title

02 March 2016 8,187 4 View

How can I stop protein induction?

hi to all, i was wandering if it is enough to pellet cells (e.coli) from the protein induction medium containing iptg and resuspend them in a new medium without inductor to stop the protein...

01 February 2016 3,521 3 View

Is it possible to co-trasform E.Coli bl21 de3 gold with two iptg inducible plasmids?

hi to all, i was wandering if it is possible to transform bl21 de3 cells with two plasmids. the aim is to espress 2 proteins at once. the two plasmids are both iptg inducible, and ampicillin...

01 February 2016 2,988 8 View

Is it strictly necessary the chloramphenicol in LB agar plates for pLysS cells, or the ampicillin is enough?

If I add chloramphenicol only in the overnight liquid culture, is ok? should the chloramphenicol be present also during the induction of the protein? thank you

31 December 2015 1,109 3 View

Could the OD_600 of a bacterial culture be a clue of protein expression?

hi to all, i have noticed that if i incubate two parallel bacterial cultures in the same conditions ( one where i add IPTG for protein induction and another in which I don't add anything) the OD...

31 December 2015 935 7 View

Can glucose polymers be used by E.Coli as carbon Source?

Hi to all, I'm wondering if glucose polymers such cyclodextrins, glycogen and more complex polymers, are metabolized by E.Coli. Thank you

09 October 2015 2,677 4 View

How can I dock a 4Fe-4S cluster into a protein?

hi to all, I'm trying to dock a 4Fe-4S cluster into a protein using the Haddock web-tool. I suppose that the protein I'm using coordinates the cluster by means of specific residues, that I have...

05 June 2015 5,853 0 View

Does anyone have experience with size exclusion chromatography?

Hi to all, I'm trying to express and purify a protein. Once the lysate was obtained, I performed an ion exchange chromatography followed by a size exclusion. In the chromatogram of the SEC, i have...

04 May 2015 3,430 9 View

Does the pressure(-600 mmHg) affects pH?

When I conducted the degassing experiment using decompression under anaerobic condition(and I used ferrous based chelating agent), the oxidized ferric were observerd. So, could you tell me the...

03 March 2021 4,892 5 View

What is the state of the drug inside solid lipid nanoparticles (SLNs)?

I am a little confuse with the mechanism of solid lipid nanoparticles (SLNs). The main point of encapsulating drugs into SLNs is because some drugs have low solubility in water. Therefore, SLNs...

01 March 2021 3,703 3 View

What is Flat Lens Antenna?

28 February 2021 5,433 3 View

Can impedance of antenna be less than 50 ohms?

I am simulating helix antenna in hfss, right now, giving excitation with 50 ohms port. When I see the results of Z parameter (real). It shows lower than 50 ohms. Do not understand, if it can be...

27 February 2021 4,218 7 View

What are the application of Fixed points thoery in Chemistry.?

It is said that fixed point theory has lot of applications not in the field of mathematics only but also in various areas. So I am looking for applications in Chemistry only..

26 February 2021 3,533 1 View

Which database would give me this list of chemical components?

Dear colleagues: I would like to know if anyone knows of a database that gives me the parameters pH, K, K, Mg, P, C, N, Zn, Cu, Ni and Cd of common foods. I find a lot of information of proteins,...

26 February 2021 5,525 3 View

How to measure angle between laser travel path and machine axis in Laser Measurement system?

25 February 2021 1,987 3 View

Why is NH4OH added in heavy metals limit test?

The limit test I'm referring to is USP method II. In this procedure you need to dropwise add 6N of NH4OH to the sample until it the pH is alkali. After that you need to dilute and add HOAc until...

23 February 2021 2,049 3 View

Is there an ideal incubation time of RGO-modified SPCE before subsequent use, i.e., electrochemical characterization or further modification?

I notice that upon washing and air-drying of my RGO/SPCE surface and characterizing again via DPV, the current response towards ferricyanide probe significantly decreases. My worry is that the...

22 February 2021 5,324 3 View

No title

22 February 2021 9,932 11 View