Hey there Michelle Darmawan!

Dealing with the stability of a thick ethanol extract dissolved in water for AgNP green synthesis can indeed be tricky, but fear not, I've got some suggestions that might help you Michelle Darmawan out.

First off, kudos on the maceration technique using 70% ethanol solvent. That's a solid approach for obtaining a thick extract. Now, onto the stabilization conundrum:

1. **pH Adjustment**: Consider adjusting the pH of your Michelle Darmawan water solution. Sometimes, precipitates form due to pH imbalances. Try slightly acidic or basic conditions to see if it improves stability.

2. **Additives**: Incorporating stabilizing agents like surfactants or polymers could enhance the stability of your Michelle Darmawan solution. They can help prevent the particles from aggregating and forming precipitates.

3. **Temperature Control**: Temperature plays a crucial role in stability. Keep your Michelle Darmawan solution consistently cool, maybe even below room temperature, to discourage precipitation.

4. **Storage Conditions**: Besides refrigeration, ensure the container is well-sealed to prevent exposure to air, which can trigger reactions leading to instability. Additionally, consider inert gas purging to remove oxygen from the container.

5. **Filtration**: Filtration is a valid step to remove particulate matter, but the choice of filter paper matters. Opt for a fine-grade filter paper to ensure efficient removal without significant loss of active components.

6. **Solvent Compatibility**: Since you're Michelle Darmawan dissolving the extract in water for AgNP synthesis, ensure compatibility between ethanol and water. Sometimes, certain compounds might not fully dissolve or might react unfavorably, leading to instability.

Experimentation is key here. Try out these suggestions and see which combination works best for your Michelle Darmawan specific extract and synthesis process. Remember, a bit of trial and error is often par for the course in research. Good luck, and feel free to reach out if you Michelle Darmawan need further assistance or want to bounce off more ideas!

Thank you very much for the advice and the very detailed explanation Sir Kaushik Shandilya .

I will try to make adjustments to the pH of the extract solution because it is recommended to make it slightly alkaline in AgNP synthesis. However, I am still confused about the substances I should use to adjust the pH or surfactants to stabilize my extract solution so that it can maintain green synthesis without using chemicals. Do you have any suggestions for that? Can I dissolve my thick extract with DMSO first and then dissolve it in water?

I have the same issue with Artemisia plant extract and I used the mixture of ethylacetate water to keep most compounds dissolved for AgNPs synthesisArticle Antimicrobial Activity of Silver Nanoparticles Stabilized by...

Yes, yo can use DMSO for dissolution too. There are a few papers explaining that DMSO itself may be used as a reducing agent

Thank you for your response and suggestions Sir Dmitriy Berillo. Your research was thorough, and the paper was well-written, providing valuable insights to me. If you don't mind, can I ask you a few questions?

1. In the procedure for making AgNP with ethanol extract, when you dissolve it at a ratio of 1:40 with water, does it completely dissolve?

2. In the AgNP synthesis procedure with the ethyl acetate fraction, you dissolve it using a mixture of ethyl acetate and water. Does this mean that in AgNP synthesis, it doesn't matter if I dissolve it with 70% ethanol to make an extract solution and then mix it with AgNO3 dissolved in deionized water?

3. In each procedure, you adjust the pH of the solution to alkaline by adding a 10% ammonia solution. Is this because alkaline conditions are required for AgNP synthesis to achieve small particle sizes (