What's the best way to couple PEG to a chemical with COOH group?

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I can't see the ssDNA band after performing asymmetric PCR. Is there any way to do this?

After performing symmetric PCR, PCR purification was performed. Afterwards, asymmetric PCR was performed using the PCR purification product as a template, but no ssDNA band was confirmed in the...

08 August 2024 1,668 3 View

How can I calculate AlGaN/GaN HEMT Breakdown Voltage on Silvaco TCAD?

Hello, I'm newbie to TCAD. I wanna calculate Breakdown Voltage of AlGaN/GaN HEMT. But, my code shows just saturation. Could you please help me how to simulate Breakdown Voltage of my code? And...

25 July 2024 3,738 1 View

When making abraxane with Nab tech, why is 9:1 Chloroform&EtOH used as solvents?

Is it the best optimization ratio based on experiments?

22 July 2024 8,170 0 View

Can the -OH of hydrogen sulfate also react with isocyanate to form a urethane bond?

Can the OH of hydrogen sulfate also react with isocyanate to form a urethane bond?

07 April 2024 7,739 0 View

I have 2 questions about molar ratio in polyurethane synthesis ?

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27 March 2024 2,718 2 View

Shouldn't linear polyurethane have an R ratio of 1:1?

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25 March 2024 4,488 8 View

I have a question about reactions between chemicals (hyaluronic acid, DTA) ???

It is said that dodecyl-trimethylammonium chloride (DTA) is used to dissolve hyaluronic acid (HA) in an organic solvent such as DMF. If the experiment is conducted using the method below, will...

23 March 2024 4,395 4 View

Is stannous octoate necessary when making polyurethane?

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Is the urethane bond between diol and isocyante broken by the solvent?

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16 March 2024 5,039 9 View

Western blot transfer time?

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• What the possible Persistent Organic Pollutants and Heavy metals present in fluorspar, sediments, and water bodies around its mining area?

Approximate concentrations are require in compared with the WHO permissible limts

11 August 2024 2,723 1 View

Basis set and input instruction to calculate HOMO and LUMO using Orca for Imidazolium based organic salts?

Hey there, As a synthetic chemist delving into theoretical calculations for my imidazolium-based organic molecules, I would greatly appreciate any guidance on the appropriate input instructions...

09 August 2024 5,444 7 View

Separation of organic acids-HPLC?

Hello What should be done to separate and identify organic acids in HPC when their RetTime is the same?Like oxalic acid with Propanoic Acid.or acids that have a very close RetTime.

07 August 2024 8,782 3 View

How to convert g/kg Humic acid dose to kg/ha?

I used humic acid at 0.044 g/kg soil in my pot experiment. But finally, I have to recommend kg/ha. Each pot's soil weight was 11 kg. What is the solution?

02 August 2024 7,186 6 View

Conjugation of PEG-Amine to an Amino Acid Using EDC?

I am attempting to conjugate PEG to an amino acid at the C-terminus, for the purposes of producing nanoparticles. I have been told that PEG modified with amine groups can be used for this purpose,...

31 July 2024 2,033 1 View

How to improve peaks separation in HPLC?

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30 July 2024 435 3 View

What is the best method to detect the chemical composition of pollen ?

I have multiple small samples of grass pollen with anthers. I want to find a method to identify concentrations of proteins, lipids, and other various elements for these samples. any suggestions?

28 July 2024 5,331 1 View

EDC carbodiimide and NHS easter 's half life among different pH?

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25 July 2024 8,738 0 View

How to separate the stereoisomers compond in reaction mixture?

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23 July 2024 8,025 4 View

I want to buy Hydrothermal Synthesis Autoclave from any European company. Can anyone suggest any company inside Europe?

Thanks

22 July 2024 1,143 3 View

Rafik Karaman

Dear Joonsuk,

The reactions of carbodiimide with amines are much faster than with alcohols since amines are much stronger nucleophiles than alcohols. Therefore, the competition is likely to be negligible.

Hoping this will be helpful.

Andrei Rogoza

If some N/O-competition will occur , simple protection can help H2N-PEG-OH -> H2N-PEG-OSiMe3 (reflux with hexamethyldisilazane and removal of excess SiMe3 (on nitrogen) with MeOH (calculated amount) reflux . Monitoring by 1H-NMR.