Why the first amino acid was lost in the SPPS by using Wang resin?

08 June 2022 0 2K Report

Recently, I've been using PEG-PS type resin to synthesize some peptides, but the MS results showed that the first amino lost in all sequences but I confirmed that the first amino acid is already loaded on the resin.

Sequence1: TTIFSALGIIS

Sequence2: TTIISLLIMNK

Coupling condition: Oxyma/DIC, HATU/DIEA, PyBOP/DIEA

Resin: PEG-PS Wang resin, SD=0.32mmol/g, K/S loaded.

Cleavage cocktail: TFA/EDT/Phenol/Thioanisole/H2O= 90/2.5/2.5/2.5/2.5

Badges
Science topic

Similar topics
Chemistry
Chemicals
Solvents

More Zhiyong Qiu's questions See All

Do solar winds impact the spread of communicable disease on the earth?

We know that solar winds had a 11 year circle and also human respiratory diseases also outbroke every 11-12 year. Is there ant connection between solar wind's strength and the pandemic...

18 February 2024 6,280 5 View

How to improve the color stability of dental resin cement?

The color of dental resin cement with amine and phosphonate will change during curing process.

01 January 2024 8,541 1 View

How i move a research paper from data to the research list?

I remove a research paper shown in the data, and then I want to add it in the reasearch. But when I add it in the research, it shows that it is already in the research gate, But I couldnot find it...

05 November 2023 1,347 1 View

Does anyone have a CT scan data of metallurgical coke?

I am researching a topic related to blast furnace metallurgy and need CT scan image of metallurgical coke with pore structure. If someone can help me, I can provide the CT scan image of...

09 September 2023 1,215 3 View

Analyzing the noise and hydrodynamic performance of the propeller with OpenFOAM?

I want to analyze the noise and hydrodynamic performance of the propeller with OpenFOAM, but there is no relevant information here, I will express my thanks if you can help me +.

23 August 2023 3,276 2 View

Which indicators are important in the international trade of the cotton?

1.Which properties of cotton are recognized universally as the indicators that can affect the trading price of cotton？And to what extent? According to the price difference table of cotton on the...

02 March 2023 4,559 1 View

Compared with normal plants, what is the specific height of inferior maize plant less than to be judged as inferior maize plant?

According to the requirements of field management in the period of maize seed production and descaking, how do you judge the inferior maize from the height of the inferior maize? Is there a...

22 February 2023 8,847 0 View

Does space and time exist outside of matter?

Perhaps the space-time we come from experience is the space-time interval, which is also the space-time of physical coordinates, depending on physical events or interactions. The natural...

04 November 2022 4,865 5 View

How to determine the positive and negative of protein dihedral angles, phi and psi?

we used pymol to calculate the dihedral angles, phi and psi. However, all we got dihedral angles' values were positive, opposite to the references' values which were negative. Could you help me...

02 November 2022 5,686 2 View

Can I conduct PCA using FPKM data from RNAseq?

I only get a set of FPKM data of several different cancer cell lines from an RNAseq experiment. Now I want to conduct PCA and other clustering methods. Heard that those methods prefer a DESeq...

11 August 2022 6,328 1 View

A positively charged and 10x his-tagged protein that doesn't bind to any chromatographic resin?

Hello everyone, I am currently working on a protein that is 10x his-tagged and positively charged (predicted pI=10.16). But when I tried to use Ni-NTA column to purify the protein, it's not...

24 July 2024 7,293 4 View

What is the principle/mechanism behind aging of carbon (graphite) containing refractory mix for isostatically pressed refractories?

The resin bonded carbon containing refractories are aged before use. How time of aging is determined? And mechanism behind aging.

23 July 2024 3,205 0 View

Prevent sedimentation and maintain the suspension of powder particles in the resin ?

Hello, I am experiencing an issue with mixing micro powder with resin in a 3D printer. The problem is that sedimentation occurs after a short period (about half an hour to an hour). Could you...

23 July 2024 1,672 0 View

Any relation between resin viscosity（mPa*s）and resin relative molecule weight？why the former is used in manufacture?

https://en.wikipedia.org/wiki/Viscosity

21 July 2024 3,089 4 View

Is it possible to conjugate an NHS ester to the N-terminus of a peptide ON RESIN?

So i have a few peptides (synthesized by SPPS and not cleaved from resin) and I want to add a maleimide label. We have NHS-PEG-Maleimide and from literature it is evident that the free amine group...

18 July 2024 4,075 3 View

Recommendations for his-tag magnetic beads / resins?

Good day everyone, Trying to perform protein purification for the first time, gotta buy the whole equipment/reagents. Protein of interest 48 kDa (Antithrombin), expressed from his-tagged plasmid...

16 July 2024 3,692 6 View

Help me to identify these fungal slides?

These fungal slides are isolated from cultured Bread mold on PDA media and smear is treated with Lacto phenol Blue dye ..

13 July 2024 9,701 1 View

What is the exact procedure and materials for converting from ester to carbolic acid by base hydrolysis??

11 July 2024 4,645 3 View

What is the best way to get rid of unpleasant odour of acrylic emulsion beside redox post polymerization?

Even adding fragrance is not working

05 July 2024 741 2 View

Lipopolysaccharide (LPS) extraction problem?

Hello, all I am currently extracting LPS from E. coli MG1655 and its mutant strains. I followed several different protocols (phenol methods or phenol+diethy ether methods), but I couldn't see...

25 June 2024 7,568 1 View