What is the difference between normally dried powdered plant material and lyophilized powdered plant material?

Dear all, good day.

Wish my Msg. find you well.

Would you please inform me, when the 2024 JCR. Impact Factor will be released? If it's does. Could you please provide me the Excel List for it.

Appreciate you kind assist and effort.

Best Regards

Hi all, can anybody confirm that my calculation is correct?

250 pg/ml to micromolar ( MW is 183.20)

250pg/ml x (1mg/1000 micrograms)x(1mol/183.20g)= 1.362x10^-12 mol/microliter

mol/microliter to micromolar :

1.362x10^-12 mol/microliter x (10^6 micromolar/1 mol)= 0.00743 micromolar

Thank you !

I've been trying to synthesize NH2-HA recently, but it failed. Can someone please tell me why and how I can improve it?

The synthesis steps were as follows: I dissolved 500mg of HA in ddH2O and adjusted the pH to around 6 using dilute hydrochloric acid. Then I added 500mg of EDC and 800mg of sulfo-NHS to activate the carboxyl groups of HA, and activated for 15 minutes. After that, I added 300μL of ethylenediamine, which brought the pH to around 7-8 (this is the appropriate pH value for the reaction, theoretically). Then the reaction was carried out for 2 hours. The whole procedure was carried out at room temperature.

Dear Researchgate Community,

I am currently trying to couple taurine to a protein via EDC reaction. I have already tried the following attempts:

1) Direct coupling at either pH 5 - 6, by only using EDC

2) Direct coupling in a two-step reaction with the aid of NHS

3) Succinylation of the lysine residues of the protein, then coupling by EDC only at pH 6

For all attempts, I have used around 7-fold molar excess of EDC to expected -COOH groups of the protein, and around 9-fold molar excess of taurine, if not even up to 20-fold.

The way I analyze "coupling efficiency" is by measuring the zeta potential of the dialyzed product at different pH, in hopes that since taurine "masks" lysine residues and offers a sulfonic acid instead, the IEP must drift to more acidic pH values. After succinylation alone, such a drift could be observed, but after EDC reaction, I keep finding an IEP that is been even more basic than my native protein, which could be caused by side-reactions due to EDC. After EDC/NHS reaction, the IEP is unchanged compared to the native protein.

I have found a paper (doi: 10.1007/bf01046841) in which taurine was succesfully coupled to succinylated ovalbumin and couldn't find anything that I did differently in terms of pH and amounts of reagents. My only "weak points" would be the total volume I'm working with. Judging by this, I have always used more concentrated solutions of protein, taurine and EDC (by using less water). I wouldn't expect this to impact the reaction, but I might be very mistaken. Does anyone have experience or knowledge about this?

I would be very much thankful for any help. Could it really be the reaction volumes? Am I using too much EDC, facilitating the reaction to N-acyl-urea derivates (although I have found similar amounts of EDC in literature, and have used the same amount to successfully couple ethylenediamine to the same protein before)? Am I overlooking something vital?

Thank you in advance.

I had a ready calculation table for my sequence that I made a peptide, but I wanted to understand the formula behind this calculation

if I have 5 equivalent of Serine with its molar mass 383.4 g/mol, resin scale 0.1mmol, total VL 2.1ml, Concentration 0.5 mol/L, and dissolved VL is 1.777ml

I am not sure this is the write Formula: Mass of amino acid = equivalent x molar mass x (resin scale mmol x 0.001mol/mmol) x total VL (ml)

But I don't know to get the dissolving VL of the DMF that need to dissolve the amino acid.

Also, I need to know if there is different formula for the coupling reagent DIC (0.5M) in DMF, its equivalent = 5, Mm = 126.2 g/mol, Total VL =24ml, and dissolved VL = 22.142ml, what is the amount of DIC that need to added to DMF?

Thank you

Facing an issue with H2o2 control experiments with cancer cell line. Could anyone help me.

Thanks

Hi there,

I have a stock concentration of drug that is 100ug/mL.

I need to make up media (500mL) so that it contains 0.33ug/mL, so how do I work out how much of the stock drug to add?

I normally work in mM and uM so using ug/mL is really throwing me off!

Many thanks

Hello,

I have an experiment in which I treated 3 bean plantations under different watering conditions in order to demonsatrate the effects of heavy metals in bean plant growth (Control: water treatment, Experimental 1: CuSO4 treatment, Experimental 2: CoSO4 treatment).

I am expected to compare the shoot lenght meassurements from Week 1 vs Final Week.

How can I demonstrate satistical differences between the groups during these weeks? (I am thinking on performing an ANOVA test or a Repeated Meassures ANOVA, but do not know how to imput my data).

I am using SPSS to run all my statistics.

Thank you!