Diluents Abdullah Al Noman Daffodil International University
Diluents Diluents are fillers used to increase the bulk volume of a tablet diluent active pharmaceutical ingredients product adequate weight and size. Diluent is a liquid used in coatings to dilute so that it can easily flow. It reduce the consistency of coating. The water used in latex coatings to thin it. In this case water is a diluent. Diluent is also known as many terms such as: Reducers, Thinners, Reducing agents, or Reducing solvents.
A diluent is a diluting agent to easily flow of solutions. It reduces viscosity of different mixers or solutions thereby it smoothly flow through holes or on the surface. It added in coatings or paints to ease the flow. Common available diluent include: Water Paint thinner Kerosene or diesel Benzene or phenol
Classification of diluents There are two types: 1) chemical nature 2) solubility
Difference Between a Solvent & Diluent ? Solvents may or may not make the chemical compound thinner and easier to use. Diluents are used for this purpose . Conversely , diluents will not necessarily put a compound into solution. An appropriate solvent is needed for this purpose.
Purpose of diluents : To enhance bulkiness To provide improved cohesion To enhance flow To allow direct compression manufacturing
Properties of diluents: Inert Nontoxic Biocompatible Stable Acceptable Non-hygroscopic Commercially available in acceptable grades Colour-compatible No harmful effect on bioavailability of drugs.
Selection of diluents : Compatibility Flowability Solubility D isintegration qualities H ygroscopicity lubricity S tability
Effects of diluents : • Degradation of API (hydrolysis ) • Mannitol - punch filming/ picking • Sucrose – tablet hardness-poor disintegration • Capping – low moisture • complex formation
How do you calculate dilution? To make a fixed amount of a dilute solution from a stock solution, you can use the formula : C 1 V 1 = C 2 V 2 where : V 1 = Volume of stock solution needed to make the new solution. C 1 = Concentration of stock solution. V 2 = Final volume of new solution . C2=?