Pharmaceutical and Formulation Consideration (part-1)

Hello, readers, I'll be discussing few rules regarding pharmaceutical dosage formulation considerations which appear to be the most prominent key features and it will be consisting in a series so stay with me and explore more through my journey here. Phase rule: It refers to the conditions under which one or more phases, a part of homogenous system, can exist is called phase rule, which can be represented by the following mathematical expression;                                           F=C-P+x Where;                F=number of degrees of freedom;                C=number of components;                P=number of phases; and                X= variable dependent upon considerations of the phase                diagram; Using this particular rule, a diagram can be obtained, by plotting a graph where temperature taken in Y axis and composition on the X axis, known as phase diagram, well, actually this type of diagram represents the melting point as a function of composition of two or three component systems.

This phase diagram clearly depicts a two-component mixture in which the components are completely miscible in the molten state and no solid solution or addition compound is found in the solid state. Now, Starting from the extremes of either pure component A or pure component B, as the second component is added, the melting of the pure component decreases. There is a point on this phase diagram at which a minimum melting point occurs similar to the eutectic point. According to the diagram, four phases are obtained as;                                       I. solid A+ solid B                                       II. Solid A+ melt                                       III. Solid B+ melt                                       IV. Melt Phase: A phase is defined as an any homogenous and physical distinct part of the system having all physical as well as chemical properties remain same throughout the system. For example; A system containing liquid water and water vapour is a two phase system. Importance: 1.It is very useful to understand the effect of intensive variables such as temperature, pressure or concentration between chemical constituents. 2. It is applicable to macroscopic systems, hence, no information is required regarding molecular or macro structure.