What is a solvate crystal?
Solvates or pseudopolymorphs are different crystalline forms of the same compound with association of solvent within the crystal lattice in a stoichiometric or non-stoichiometric ratio and are quite different from the polymorphs of the same drug molecule (4).
What does solvate mean in chemistry?
Definition of solvate (Entry 1 of 2) : an aggregate that consists of a solute ion or molecule with one or more solvent molecules also : a substance (such as a hydrate) containing such ions.
What does polymorphic mean in chemistry?
polymorphism, in crystallography, the condition in which a solid chemical compound exists in more than one crystalline form; the forms differ somewhat in physical and, sometimes, chemical properties, although their solutions and vapours are identical.
What is solvate and hydrate?
Hydrates and solvates are thus multicomponent crystalline solid molecular adducts containing both the host molecule (API or excipient) and guest molecule (water (hydrate) or other solvents (solvate)) incorporated in the crystal lattice structure, commonly known as pseudopolymorphic forms.
How do you make a Cocrystal?
Grinding, both neat and liquid-assisted, is employed to produce cocrystal, e.g., using a mortar and pestle, using a ball mill, or using a vibratory mill. In liquid-assisted grinding, or kneading, a small or substoichiometric amount of liquid (solvent) is added to the grinding mixture.
Are hydrates polymorphs?
As a consequence, they may also have different physical and chemical properties than their anhydrous counterparts. These parallels to polymorphs are the reasons hydrates were previously called pseudo-polymorphs [4,5].
What is the meaning of association in chemistry?
chemical association, the aggregation of atoms or molecules into larger units held together by forces weaker than chemical bonds that bind atoms in molecules. The term is usually restricted to the formation of aggregates of like molecules or atoms.
What do you understand by association?
noun. an organization of people with a common purpose and having a formal structure. the act of associating or state of being associated. friendship; companionship: Their close association did not last long. connection or combination.
What is polymorphous answer?
Polymorphous : A single substance which crystallises in two or more forms under different conditions of solidification is called polymorphous. Polymorphic forms are called polymorphous. Polymorphic forms are called allotropic forms or allotropes. For example, carbon exists as rhombic and monoclinic allotropic forms.
What does the term polymorphic mean?
: the quality or state of existing in or assuming different forms: such as. a(1) : existence of a species in several forms independent of the variations of sex. (2) : existence of a gene in several allelic forms also : a variation in a specific DNA sequence.
Why do hydrates form?
Hydrates form naturally when ionic compounds are exposed to air and make bonds with water molecules. Specifically, the bond is formed between the cation of the molecule and the water molecule. The water that remains is usually known as water of hydration or water of crystallization.
What is the difference between crystal and cocrystal?
is that crystal is (countable) a solid composed of an array of atoms or molecules possessing long-range order and arranged in a pattern which is periodic in three dimensions while cocrystal is (organic chemistry) a crystal, often a large-molecule crystal, having two or more distinct molecular components within the …
What is a solvate?
Definition of solvate (Entry 1 of 2) : an aggregate that consists of a solute ion or molecule with one or more solvent molecules also : a substance (such as a hydrate) containing such ions
What is the difference between hydrates and solvates?
Solvates are crystals that have incorporated solvent molecules into their crystal lattice, hydrates have incorporated water molecules as such. Amit Bhatia, Rakesh K. Tekade, in Dosage Form Design Parameters, 2018 Crystal solvates tend to form during the process of crystallization with the help of a solvent.
What is the use of solvates and hydrates in cocrystals?
Solvates and hydrates provide a way of increasing the number of related solid forms for a cocrystal.
Why do small molecules form solvates and hydrates easily?
Most small molecular weight APIs and excipients tend to form solvates and hydrates readily due to their small molecular size. Water molecules have both hydrogen bond donor and acceptor atoms, which can form intermolecular hydrogen bonding with host molecules.