Determination of Ash content

Definition Ash Value The residue remaining after incineration is the ash content of the drug. Inorganic salts of carbonates, phosphates, silicates of sodium, potassium, calcium and magnesium. Ash value is a criterion to judge the identity OR purity of the crude drug. A high ash value is indicative of contamination, substitution, adulteration or carelessness in preparing the crude drug for marketing

Ash value Physiological Ash: Which is derived from the plant tissue itself Non – physiological Ash: Which is the residue of the adhering material to the plant e.g. Sand and soil.

Ash value Ash value can be determined by three different methods: Total Ash Total ash method is used to measure the total amount of material remaining after incineration Acid insoluble Ash Acid insoluble ash is the residue obtained after boiling the total ash with dil. HCl and igniting the remaining insoluble matter. Water soluble Ash Water soluble ash is the difference in weight between total ash and residue after treatment of total ash with water.

Heat at 450°C until free from carbon Total Ash Weigh accurately about 3gms of the powdered drug in a tared silica crucible Heat at 450°C until free from carbon Cool and weigh

Acid insoluble ash Total Ash Add10 mL 3N HCL and boil for 5 mins Filter through ashless filter paper Ignite at 450 C° Cool and weigh

Water soluble ash Total Ash Add10 mL water nas boil for 5 mins Filter through ashless filter paper Ignite at 450 C° Cool and weigh