Neutral Fraction
Definition
The organic phase recovered when the aqueous is buffered to pH 7 to 9 and extracted with a less polar solvent like methyl tert-butyl ether or ethyl acetate. Carries the weakly basic and neutral drugs: benzodiazepines, zolpidem, carbamazepine, phenytoin and legacy methadone and propoxyphene.
Related terms
- Acid Fraction
- The organic phase recovered when the biological aqueous is acidified to pH 2 to 3 and shaken with diethyl ether or chloroform....
- Alkaline Fraction
- The organic phase recovered when the aqueous is basified to pH 9 to 10 with ammonium hydroxide or sodium hydroxide and shaken...
- Cut-Off
- The minimum analyte concentration that an SFSL reports as positive. SAMHSA-style serum cut-offs commonly used at Indian labs include morphine 2 ng/mL,...
- DFC
- Drug-facilitated crime, the umbrella term for sexual assault, robbery or kidnapping in which a victim has been incapacitated by a clandestinely administered...
- pKa
- The negative logarithm of the acid dissociation constant. For a basic drug it is the pH at which half the molecules are...
- Post-Mortem Redistribution
- The movement of drugs from solid tissues into central blood after death, due to diffusion along concentration gradients, autolytic enzyme release, and...
Explained in
- Acidic, Neutral and Alkaline Drug AnalysisThe organic phase recovered when the aqueous is buffered to pH 7 to 9 and extracted with a less polar solvent like methyl tert-butyl ether or ethyl acetate. Ca...