How does lipophilicity affect permeability?
Lipophilicity has also been found to affect a number of pharmacokinetic parameters: higher lipophilicity gives, in general, lower solubility, higher permeability in the gastrointestinal tract, across the blood–brain barrier and other tissue membranes, higher affinity to metabolizing enzymes and efflux pumps, and higher …
What does logP indicate?
So, what exactly is logP? LogP, or octanol-water partition coefficient, is a measure of how hydrophilic or hydrophobic a molecule is. It indicates how readily an analyte will partition between an aqueous and organic phase.
What is a good logP value?
It is generally considered that compounds with a logP greater than 1 or less than 4 are more likely to have optimal physicochemical and ADME properties for oral drugs.
What is the difference between logD and logP?
logD is a log of partition of a chemical compound between the lipid and aqueous phases. The most popular lipid phase is octanol. LogP is equivalent to logD for non-ionisable compounds and represents the partition of the neutral form for ionizable compounds (and, hence, is a virtual, unmeasurable, property).
What is the difference between Lipophobic and lipophilic?
Lipophilic signal molecules enter the cell and bind to receptors INSIDE the cell (either cytoplasmic or nuclear receptors). Lipophobic signal molecules bind to membrane receptors located on the OUTSIDE surface of the cell.
What is difference between hydrophilic and lipophilic?
The classification of drugs as hydrophilic or lipophilic depends on their ability to dissolve in water or in lipid-containing media. In this respect, absorption is faster in lipophilic drugs, whereas the ease for renal excretion is greater in hydrophilic medications.
Is cLogP same as logP?
What is the difference between logP and ClogP? Solution: They are just two different methods for calculating logP. Log(p) (partition coefficient for n-octanol/water) – three fragmentation methods are used to predict the log(p) values.
What is a good cLogP?
A molecule possessing cLogP 4.5–5 and molecular weight 450–500 is “rule-of-5 compliant” on these properties (cLogP < 5 and molecular weight < 500), but because these cut-offs are defined by 90th percentile values, only 1% of oral drugs are in this range.
Is cLogP same as LogP?
What do you mean by Lipophobic?
Adjective. lipophobic (comparative more lipophobic, superlative most lipophobic) (chemistry) Having no affinity for fats or organic solvents.
What is an example of lipophilic?
Nimodipine has lipophilic properties and can easily cross the blood-brain barrier. The drug is highly lipophilic and able to cross the blood brain barrier at higher doses. This example is from Wikipedia and may be reused under a CC BY-SA license.
Why HLB value is important?
As the HLB value increases, the emulsifiers become more soluble in water and their function changes from being W/O emulsifiers to being O/W emulsifiers. HLB values are useful for selecting the most appropriate type of emulsifiers for food application.
Is lipophilic polar or nonpolar?
Lipophilic refers to the ability of a substance to dissolve in lipids or fats. Since lipids and fats are nonpolar, lipophilic substances are also nonpolar (according to “like dissolves like” rule).
What is CLogP value?
CLogP is the ratio of two measurements using the same unit, so it’s a unitless or dimensionless value, lacking its own unit of measure. It’s possible to measure an actual log(P) value using two solvents, n-octanol and water.
How is LogP value calculated?
logP calculations are based on a pool of fragments predefined in the calculator. This set is based on the data set in references 1. Every fragment is assigned a unique name and a value. The logP value of a molecule is the sum of the fragment values present in the molecule.
Is CLogP and logP same?
What is HLB value explain?
HLB is an index of the solubilizing properties of emulsifiers and indicates the type of emulsion (o/w or w/o) that the emulsifier is best suited for (Table 2). HLB values can be calculated based on the molecular structure of the emulsifier or determined empirically.
What does low HLB value mean?
Lower HLB numbers indicate better oil (non-polar) solubility. Higher HLB numbers indicate better water (polar) solubility. Surfactants with low HLB values are more suited for water-in-oil emulsions (W/O), and higher HLB values are better for oil-in-water emulsions (O/W).
Whats the difference between hydrophilic and lipophilic?
The key difference between lipophilic and hydrophilic is that lipophilic refers to the ability of a substance to dissolve in lipids or fats while hydrophilic refers to the ability of a substance to dissolve in water or other hydrophilic solvents.
Is cLogP and logP same?
What is cLogP value?
What is the range of HLB value?
The HLB Scale ranges 1-20. Surfactants with higher HLB numbers (greater than 10) are more hydrophilic. Surfactants with lower HLB number (less than 10) are more hydrophobic (lipophilic) Complete water solubility of a surfactant occurs at and HLB of approximately 7.3.
Why HLB scale is used?
The most commonly used is HLB. HLB is an index of the solubilizing properties of emulsifiers and indicates the type of emulsion (o/w or w/o) that the emulsifier is best suited for (Table 2). HLB values can be calculated based on the molecular structure of the emulsifier or determined empirically.
What is required HLB value?
The Required HLB for making W/O emulsions of any material will lie in the range of 3 to 8; for solubilization in water, in the range of 10 to 18.