Panarin Chinavinijkul

11 Questions 13 Answers 0 Followers

Questions related from Panarin Chinavinijkul

How does Silane-modified ZnO nanoparticles works, how much Silane is added?

I have a question regarding the synthesis/modification of ZnO Nanoparticles (NP) with a silane. I had a general idea of how ZnO and Silane interacts but I am not sure how the amount of required...

28 October 2021 9,750 11 View

Why are multiple different Vancomycin Absorbance Spectrum used?

I was looking through quantification of Vancomycin using UV absorbance spectrum and I came across multiple papers that uses wavelength around 215-240 nm for UV detector in HPLC whereas the most...

26 June 2018 1,566 4 View

Why does my Freeze-dried (drug) product turned into web-like fiber?

This happened when I tried to freeze-dried Vancomycin that I want to recover from my experiment (in water). I tried precipitating the product in water-miscible solvent that Vancomycin are not...

26 June 2018 8,297 3 View

Vancomycin - left in solution for a month - precipitated, then changed color when added NaOh to change pH from low to high. Changed into what?

This perplexed me the first time I saw it. I prepared a solution of Vancomycin in DI water with concentration of 5 mg/ml. The solution was used as a dipping solution where the substrate was...

04 June 2018 4,131 0 View

How do you determine the purity and consistency of biological drugs?

I bought another batch of Vancomycin a while back; however, this batch has a brownish color instead of white like the previous one. According to Sigma, the range of color for vancomycin can be...

11 April 2017 4,709 7 View

The best/cheapest way to detect Gentamicin release rate from implant?

I was looking around for method to determine the amount of Gentamicin released from an implant but all the methods I found involved either derivation, HPLC, CE, etc. I was wondering what is the...

03 March 2017 9,419 0 View

Can I obtain a thorough and/or uniform thickness dip-coating on a bone plate?

I would like to add a coating layer onto a bone plate however, I am running into question I am unsure about. Most of the papers I look through do not have a detailed info on their dipping...

19 October 2016 4,215 3 View

Measuring Molecular Weight of Polymer from Kinematic Viscosity?

From what I know, you can use intrinsic viscosity to measure the molecular weight of polymer via Mark-Houwink's Eq., which needs the Ubbel equipment. I know GPC is an option but I am trying to...

14 September 2016 1,106 8 View

Effect of gradual increase of pressure on polycondensation's MW?

Hi, I am trying to synthesize PLA with high molecular weight. The method that I have been using can give me at most 50kDa. Based on the paper I've been following, it should be able to increase...

06 September 2016 3,038 4 View

Why is about half N-acetylated Chitosan soluble in water at neutral pH?

Why is it that at higher or lower N-acetylated value (e.g. 20, 80), it is insoluble in water, but soluble at half (50%)? In addition, I have been confused for a while regarding the definition of...

01 January 1970 928 2 View

How to perform long-term (e.g. 30 days) bacterial testing for orthopedic implant?

I want to do a long-term bacterial testing for orthopedic implant to determine if my antibacterial coated external fixation is capable of prolonging bacterial formation. What I am stuck on is how...

01 January 1970 2,902 8 View