Any other vendors?

More David Hart's questions See All

• 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

Adhesion strength of coating?

How can I determine a good adhesion strength range for coatings on polymer surfaces, such as DLC on polymer substrates? Is there a specific threshold for adhesion strength (from T-peel tests)...

10 August 2024 942 3 View

Polymer wear calculation?

What is the method for analytically calculating the wear and service life of polymer-polymer sliding pairs?

04 August 2024 1,078 1 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

Why Powder XRD is performed after cruhsing a crystal if Single Crystal XRD analysis of the same crystal has been performed already ?

What information we can get from PXRD analysis other than from SCXRD analysis of a crystal ?

30 July 2024 6,261 4 View

Why is it not common to see similar pairs in polymer sliding pairs?

If the pairs are similar, will it reduce the adhesion due to electric charges?

29 July 2024 3,185 2 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

The importance of humanistic care?

Humanistic care is mainly about caring for people's living conditions, affirming people's living conditions and dignity, and pursuing human freedom and liberation. With the continuous development...

10 July 2024 5,107 2 View

How does the crystallite size and microstrain distribution influence the mechanical properties of a ceramics?

10 July 2024 3,444 4 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

Which type of compound does lamda max of 218 indicate in a uv-vis spectrum of a partially purified compound through column and TLC?

A crude extract of fungal culture using EtOH was subjected to column and TLC and partially purified compound was obtained. UV vis spectrum of the compound/s has max absorbance at 218nm. The...

11 August 2024 9,801 2 View

Can you connect an HPLC to a Mass Spec only at a certain time point?

Can anyone explain this method? Especially the last statement where it says only at 1.5 to 2.5mins was the MS/MS connected to the UPLC. How is that possible, is it a feature in this specific...

11 August 2024 8,141 3 View

Geotechnical Engineering (Proceedings of the ICE) time review?

Hello everyone, I recently submitted an article to Geotechnical Engineering (Proceedings of the ICE), and the current status has been listed as "EiC Pre-assessment: Ready" for the past 20 days. I...

10 August 2024 6,493 1 View

How to confirm the site-directed mutagenesis result without performing NGS?

I'm cloning a fragment of 3200 nts into plasmid. The cloning was successful, however, 02 amino acids were mutated. Now I want to fix these 02 aa by site-directed mutagenesis technique using...

08 August 2024 4,645 2 View

GC-MS retention index prediticon?

Hello experts, Does anyone know any free software about retention index prediction ?

08 August 2024 7,403 2 View

How to calculate CCS for Sodiated adduct ions and Multiply Charged Ions?

I'm currently working on calculating the collision cross section (CCS) for various ions, and I'm facing challenges when dealing with sodiated and multiply charged ions. Most of the resources I’ve...

08 August 2024 8,329 0 View

Can I use a HisTRAP column for affinity chromatography?

I'm working on selecting antibodies against a recombinant protein that has a His-tag. My idea is to first bind the recombinant protein to a HisTRAP column and then use this column for an affinity...

07 August 2024 505 3 View

Are there instances where molecules with larger molecular weights exhibit greater mobility than those with smaller molecular weights?

Hi, I know that low molecular weight (MW) molecules generally tend to have higher mobility, while high molecular weight molecules tend to have lower mobility. However, in my experimental...

06 August 2024 1,495 2 View

Weak DAPI staining after immunohistochemistry - how to improve?

After immunohistochemistry of previously fixed in PFA and EtOH and then frozen 20 μm sections of zebrafish brain, DAPI staining is very weak (right) compared to the same sections stained without...

05 August 2024 9,637 2 View

The Curse of Evolution and Complexity?

Brain and body mass together are positively correlated with lifespan (Hofman 1993). The duration of neural development is one of the best predictors of brain size, and conception is the best...

05 August 2024 6,247 3 View

Giancarlo Lopez-Martinez

How much is Biorad's. I used to use Sigma's when I did it (5 yrs ago) but it was not cheap (I do not recall).

David Hart

Biorad is $430 for 100g, Sigma is $154 for 100g. Sigma is by far the cheapest I have seen Thanks!

Nick Chacos

just google mixed bed ion exchangers. You will find dowex, purolite and several others easily. Did a quick check and Purolite sells 1 cubic foot for $305. The suppliers you buy from simply buy these bulk chemicals and repackage.