Abstract
Context: Rasa Karpura (RK) is a mercurial preparation, well known to treat Krimivisha (worms), Pravahika (cholera), Phiranga (syphilis), Twakroga (skin diseases), Upadansha (gonorrhoea) with specified adjuvants. It is prepared by Hingulottha Parada (processed mercury), concentrated Sulphuric acid and Saindhava Lavana in a proportion of 1:1½:1½ using Kupipakva method in Valuka Yantra or Electric Muffle furnace (EMF).
Aim: To validate the manufacturing procedure of Rasa Karpura.
Material and Methods: Three samples of RK were prepared by taking processed mercury and conc. Sulphuric acid, mixed together to form Parada Churna, followed by an addition of Saindhava Lavana. Further, the obtained mixture was processed by Kupipakva method in EMF for 12 hrs. of heating. On cooling down, the Rasa Karpura was collected from the neck of Kupi.
Results: Average 75.5 % of Parada (Mercury) was extracted from processed Hingula (Cinnabar). 60% of average Parada Churna was obtained from 100 g of Parada and 150 ml of sulfuric acid with an average heating duration of three hours and twenty-eight minutes. Appearance of pungent smell was observed when Parada Churna and Saindhava Lavana were triturated. Average yield of Rasa Karpura was 39.22% and was white in color with crystal texture and spike like appearance.
Conclusion: Pharmaceutical preparation of Rasa Karpura requires 12 hours continuous intermittent heating pattern subdivided into 4 hrs of Mridu Agni (Mild heat, 1500C- 2500C) and 8 hrs of Madhyama Agni (Moderate fire, 2500C- 3250C). The detailed data provided in the present study may serve as reference document for academia and pharmaceutical companies to manufacture Rasa Karpura. This study also emphasizes on importance of testing of Rasa Karpura according to Parada Vigyaniyam.

Key words: Kupipakva Rasayana, Mercury, Mercury chloride, Parada, Rasashastra, Standardization.