Answer Posted / ravi kumar thota
Silica is an amorphous polymer of silicon and oxygen. This polymer terminates at the surface of the particle as –Si-OH groups, commonly called “silanols.” These silanol groups serve as attachment sites for the bonded phase. A silane reagent, such as Cl(CH3)2SiC18H37 is reacted with the silanol to form a silyl ether (–Si-O-Si-). The bulk of the C18 group prevents bonding to all of the exposed silanols. This results in a surface that looks much like that on the left side of Figure 1, where there is a fairly high population of unbounded silanols, often termed “residual silanols.” The residual silanols are somewhat acidic and can be overly reactive with sample components, especially basic analytes, so it is preferable to reduce the population of residual silanols.
| Is This Answer Correct ? | 0 Yes | 0 No |
Post New Answer View All Answers
If change in specification which parameter require to do for validation? if change in chromtographic condition then which parameter? if api change then which parameter? if change composition then which parameter? if old method not work out then whicj parameter? if additional one impurity added then which parameter of validation require to do on above each conditions? elaborate separately
in which situation require to use paddle and basket?
on saturation solubility study data how we can find out the bcs class of drug?
A ha tc is actual defination of retention time?
How do we fix the sample concentaryion in hplc method development. What is the basis?
what are risk assement in the analytical qbd?
WHAT IS THE USE OF STARTER ?????????
What should be the level/ Percentage of Arsenic in Arsenic free zinc.
Ratio of Water and Acetonitrile(diluent) is not recommended to use in cleaning method validation,why?
how to set sample and standard concentration in RS method?
if you get peak in blank then what require to do?
What is the use of tlc and hplc? And when and where use?
How can we confirm the HPLC column is end-capped or not? Is it possible to identify by physical appearance?
How we performed the force degradation for drug substance, is any specific guideline is available for each parameter(Acidic, basic, oxidation,heat)? what conditions you mentained for above parameters.
how a particular wavelength can be different for a particular compund while analysing by uv and by HPLC.
