Common questions

What is biodistribution studies?


What is biodistribution studies?

Biodistribution studies are often performed using radioactive tracers. Immunohistochemistry biodistribution studies help identify differences between the animal model species and humans in epitope level of expression, the affinity of a mAb for the epitope, or the cellular response to mAb binding.

Why is biodistribution important?

Biodistribution components in relevant species or models are therefore among the most fundamental preclinical information on the GTMP to be collected, because they will inform on the potential target organs and tissues and will allow anticipation of which on-target or off-target effects might be expected.

What is ex vivo biodistribution?

Ex-vivo biodistribution results showed highest tumor accumulation and tumor-to-muscle ratio of (18)F-FDG at each time point, accompanied by physiologically high uptakes in the brain, heart, and intestinal tract.

What is in vivo biodistribution?

Biodistribution studies showed a greater accumulation of nanoparticles in liver, spleen and stomach than in kidney, heart and lungs. The results demonstrate that these multimodal nanoparticles have potentially ideal attributes for use as biocompatible probes for in vivo imaging.

What is volume of distribution of drugs?

The volume of distribution (VD) relates the amount of drug in the body to the concentration of drug in the plasma. It is calculated by dividing the dose that ultimately gets into the systemic circulation by the plasma concentration at time zero (Cp0): (1)

What is biodistribution and pharmacokinetics?

The pharmacokinetics (PK) and tissue distribution of the nanoparticles largely define their therapeutic effect and toxicity. Chemical and physical properties of the nanoparticles, including size, surface charge, and surface chemistry, are important factors that determine their PK and biodistribution.

What is biodistribution of elements?

Bio-distribution of elements means the relative abundance of elements in biological systems. In almost all life forms on earth (weather in land or in oceans) carbon, nitrogen, oxygen and hydrogen are the chief elements making up most of the body mass of the organisms.

Which drug has highest volume of distribution?


Drug VD Comments
Warfarin 8 L Reflects a high degree of plasma protein binding.
Theophylline, Ethanol 30 L Represents distribution in total body water.
Chloroquine 15000 L Shows highly lipophilic molecules which sequester into total body fat.
NXY-059 8 L Highly charged hydrophilic molecule.

Which types of drugs have high volume of distribution?

3.2. Some drugs (e.g. tolbutamide, phenytoin, gentamicin, warfarin) are known to have small volumes of distribution (0.1–1 L/kg) while others (e.g. meperidine, propranolol, digoxin) are known to have large volumes of distribution (1–10 L/kg).

What is a high Vd?

A drug with a high Vd has a propensity to leave the plasma and enter the extravascular compartments of the body, meaning that a higher dose of a drug is required to achieve a given plasma concentration. (High Vd -> More distribution to other tissue) (Low Vd -> Less distribution to other tissue)

Which type of drug has fairly high apparent volume of distribution?

Its apparent volume of distribution is close to total body water. Because it does not bind to plasma proteins this suggests it does not bind extensively to tissues either. Digoxin has a very large apparent volume of distribution – several times bigger than the typical human physical volume of 70 L.