Which methods are best to analyze humic and fulvic acids in soil?

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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

Hot to do MTT assay data analysis?

I have repeated an MTT assay three times using different batches of the same cell line. Each time, I tested the same treatment (different medium) and seeded the same number of cells. Additionally,...

08 July 2024 1,900 1 View

What is wrong with Site-Directed Mutagenesis?

I am following the NEB protocol to perform SDM with Q5 and NEB HiFi Assembly. I am making a two base pair change. First picture is my Primers designed with NEBaseChanger. Second Picture is my...

24 June 2024 6,079 4 View

Does anyone have suggestions for this esterification?

I have a very polar alcohol (soluble in MeOH, H2O, partially in heated DMSO). And a long chain fatty acid that I would like to couple. I can't find a common solvent for them. I can form the...

24 June 2024 9,319 0 View

How do you add multiple nodes or cutting planes in Abaqus?

Hi, In a previous question I asked how to effectively model springs in Abaqus. However, I figured out the feature under Assembly -> springs/dashspots -> node to node Springs. I have a cylinder...

20 June 2024 892 3 View

How do you add radial spring elements in Abaqus?

Hi, I am trying to complete a buckling analysis on a tube with an external pressure. This solves itself easily by adding radial constraint on the internal edge of the tube, one axial constraint...

17 June 2024 8,165 7 View

Given that Mesozoic placentals were largely arboreal (with fingers), do you know of any studies that illustrate the finger-to-hoof transition?

I'm interested in the earliest days of placental terrestrial locomotion in large herbivorous taxa. Phenacodus seems to be transitional in this regard. Any others?

06 June 2024 5,182 2 View

How reliable is ninhydrin test in solid-phase peptide synthesis?

Hey everyone! I'm doing peptide synthesis on Rink amide resin and sometimes I need to add amino acids with secondary amines or beta amino acids. Normally I synthesize 35 to 40 mer peptides. As a...

21 May 2024 9,035 0 View

How does one generate a normalized TCSPC curve from actual photon counts versus time?

Sometimes TCSPC curves are analyzed using the actual photon counts, and sometimes they are normalized with the signal running from 0 to 1, or even from 0 to some value less than 1. What quantity...

20 May 2024 4,277 0 View

Problem when running Spin-Orbit Coupling using CASTEP. What is nlpot_prepare_precon_ks?

I am currently using CASTEP version 22.11, and I encounter the following error when running calculations with spin-orbit coupling: Error with dsytrf in nlpot_prepare_precon_ks Current trace...

19 May 2024 4,236 5 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

The aqueous fraction of the hydroethanolic extract is showing the presence of palmitic acid. What is the mechanism responsible ?

Palmitic acid presence in aqueous fraction

05 August 2024 8,624 4 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

Inquiry on Maximum Nucleic Acid Volume for 2.5 mL Liposome Solution?

I am currently working on a project involving liposomes and need to determine the maximum volume of siRNA that can be added to a 2.5 mL liposome solution with a total lipid concentration of 10...

30 July 2024 6,420 1 View

Why is trifluoroacetic acid (TFA) used in c-18 column?

I would like to know the role of the TFA (trifluoroacetic acid) used on reverse phase chromatography c-18 column. It's is often used with a concentration of 0.1% on the mobile phase.

23 July 2024 8,075 3 View

Can we add calcium carbonate to any media as an indicator for lactic acid producing bacteria?

As mentioned in literature the addition of CaCO3 to MRS Agar media is considered as an indicator for lactic acid producing bacteria, so I wonder if we can add CaCO3 calcium carbonate to any other...

20 July 2024 7,504 0 View

What is the suitable solvent of MIL-100 for chemotherapy?

I synthesised a nanocarrier by conjugation MOF (MIL-100) with folic acid for use in chemotherapy but the samples didn't dissolve completely in aqueous solution or DMSO. Instead, they only...

19 July 2024 8,522 0 View

Can I use candle-jar technique to lactic acid bacteria?

I don't have the anaerobic generators (Anaeropac) so I'd like to try the candle-jar tecnique for the cultive of lactic acid bacteria

15 July 2024 8,890 2 View

What is the suitable solvent of MIL-100 for chemotherapy?

I synthesised a nanocarrier by conjugation MOF (MIL-100) with folic acid for use in chemotherapy but the samples didn't dissolve completely in aqueous solution or DMSO. Instead, they only...

15 July 2024 2,414 1 View

Should all lactic acid bacteria be catalase negative? should all probiotic bacteria be catalase negative?

I am working on probiotic bacteria for fish, and I am trying to isolate probiotic bacteria like lactic acid bacteria or other probiotics from the gastrointestinal tract of fish using different...

12 July 2024 3,756 4 View