|Year : 2012 | Volume
| Issue : 4 | Page : 164-170
Quality control parameters for Tamra (copper) Bhasma
Chandrashekhar Yuvaraj Jagtap1, Pradeepkumar Prajapati1, Biswajyoti Patgiri1, Vinay J Shukla2
1 Department of Rasashastra and Bhaishajya Kalpana Including Drug Research, I.P.G.T. and R.A., G.A.U., Jamnagar, Gujarat, India
2 Pharmaceutical Chemistry Laboratory, I.P.G.T. and R.A., G.A.U., Jamnagar, Gujarat, India
|Date of Web Publication||18-Feb-2013|
Chandrashekhar Yuvaraj Jagtap
Department of Rasashastra and Bhaishajya Kalpana Including Drug Research, I.P.G.T. and R.A., G.A.U., Jamnagar, Gujarat
Source of Support: None, Conflict of Interest: None
Background: Metallic Bhasmas are highly valued and have their own importance in Ayurvedic formulations. To testify the Bhasmas various parameters have been told in Rasashastra classics. Tamra Bhasma (TB) with its different properties is used in the treatment of various diseases is quiet famous among the Ayurvedic physicians (Vaidyas).
Objectives: The present study was carried out to set up the quality control parameters for the TB by making the use of classical tests along with advanced analytical tools.
Settings and Design: Copper wire taken for the preparation of Bhasma was first analyzed for its copper content and then subjected to Shodhana, Marana and Amrutikarana procedures as per the classical references. Final product complied with all the classical parameters like Rekhapurnatwa, Varitaratwa etc.
Materials and Methods: After complying with these tests TB was analyzed by advanced analytical techniques like particle size distribution (PSD) analysis, scanning electron microscopy (SEM), and inductive coupled plasma spectrometry (ICP).
Results: PSD analysis of TB showed volumetric mean diameter of 28.70 μm, 50% of the material was below 18.40 μm size. Particle size less than 2μm were seen in SEM. 56.24 wt % of copper and 23.06 wt % of sulphur was found in ICP-AES. Heavy metals like cadmium, selenium were not detected while others like arsenic, lead and mercury were present in traces.
Conclusions: These observations could be specified as the quality control parameters conforming to all the classical tests under the Bhasma Pariksha.
Keywords: Bhasma Pariksha , copper, Rasaushadhi, Tamra, quality control
|How to cite this article:|
Jagtap CY, Prajapati P, Patgiri B, Shukla VJ. Quality control parameters for Tamra (copper) Bhasma. Ancient Sci Life 2012;31:164-70
| Introduction|| |
Rising popularity of Ayurveda in recent years have increased the demand of Ayurvedic preparations. It is challenging for the Ayurvedic pharmaceuticals to produce the standard, genuine and safe drug in required quantity with utmost quality. Not only to the pharmaceuticals but also to the policy makers, consumers and to the regulatory authorities in both the producing and importing countries it becomes the matter of serious concern to come up with the efficacious and standard quality product.  'Quality' can be taken as the denominator of any product for its acceptance.  Control refers to the function concerned with ensuring the production, right from the raw materials to the finished product, to accomplish the set standards.
Metallic Bhasmas are highly valued and have their own importance in Ayurvedic formulations. Preparation of Bhasmas is very tedious and time consuming procedure. Previously the Bhasmas were prepared by the Ayurvedic physicians themselves as per their requirements. Nowadays they are manufactured in large scales in pharmaceutical houses. This new approach has created several problems, because the use of new appliances has not been standardized regarding the quality of these Bhasma preparations.  Moreover different pharmaceutical procedures used for the preparation produces the same Bhasma with different characters.  This leads to the variation in the metal content of the marketed samples containing these Bhasmas. Reproducibility is very important in the viewpoint of standardization. Hence it is the need of the hour to standardize these Bhasmas on the basis of their classical tests by using the advanced analytical techniques. For this, setting up of quality control parameters becomes necessary which will provide the standards required and minimize the variability and also check the adulteration.
Tamra Bhasma (TB) is one of its kind having the properties like Saraka (purgative), Lekhana (scraps excessive fat), Ropana (would healing), Brimhana (rejuvenator) etc. ,, It alleviates the disorders caused by Kapha and Pitta and is widely used in treatment of various diseases like Parinama Shula (peptic ulcer), Pandu (anaemia), Udarashoola (abdominal pain), Arsha (Haemarrhoids), Kushtha (skin disorders), Shwasa (dyspnoea), etc.  Raw Tamra (copper) or improperly prepared TB may cause various illnesses like Vanti (vomiting), Murccha (fainting), Bhrama (hallucination), Shula (spasmodic pain), Daha (burning sensation), Moha (delirium), Aruchi (anorexia), and even Ayunasha (death). , It is therefore very important to prepare TB of best quality. This study was carried out to set up the quality control parameters for the TB by making the use of classical tests along with advanced analytical tools.
| Materials and Methods|| |
Preparation of Tamra Bhasma
The copper wire used for the purpose of electrical earthing was procured from local electrician. Wire was quantitatively analyzed for its copper and iron content.  It was then subjected to Samanya Shodhana (general purification/detoxification), Vishesha Shodhana (special purification/detoxification), Marana (calcinations/incineration) and Amritikarana procedures as per the references. Puta (heating grade) were given in horizontal electric muffle furnace (EMF). Pilot study was carried out first to set the following temperature pattern: 1 st Puta- 700°C for 20 minutes, 2 nd Puta - 600°C for 25 minutes, 3 rd and subsequent Puta - 500°C for 30 minutes. First three Puta were given by adding equal amount of Samaguna Kajjali (Black sulfide of mercury - HgS)  and triturating with Nimbu Swarasa (juice of Citrus limon Linn.) Subsequent four Puta were given by adding equal amount of Shuddha Gandhaka (purified sulfur) and triturating with lemon juice. Dadhi Pariksha (Curd test) was considered as the main tool for finalizing the prepared Bhasma. TB passed this test after seven Puta. After passing the test, the Bhasma was subjected to Amritikarana. TB was triturated with ½ part of Shuddha Gandhaka in mortar and Bhavana of Nimbu Swarasa given. After proper trituration, a round bolus was prepared and dried in sunlight. Surana weighing 2.5 kg was cut into two halves horizontally. A round pit was made in middle of both the halves. Dried bolus was kept in it and the two halves were joined together. A thick layer of Kapadmitty (mud smeared cloth) was done over it. It was then dried in sunlight; kept in E.M.F. at the temperature of 500° C for 30 minutes. After Swangasheetikarana (self cooling) it was removed, triturated and stored in airtight glass bottle. TB was again tested by curd test.
Analysis of the final product
TB was then analysed by using different organoleptic parameters. Classical tests like Varitaratwa, Rekhapurnatwa, Apunarbhavatwa, Uttama/Unama, Niruttha, etc  and Dadhi Pariksha were performed. Other parameters like Avami, Niswaduta etc  were also applied. Modern physico chemical parameters  like loss on drying, ash value, acid insoluble ash, and water soluble extractive were performed on three samples of Bhasma. Sophisticated instrumental analytical techniques like X ray diffraction (XRD), scanning electron microscopy (SEM), particle size distribution (PSD), and inductive coupled plasma - atomic absorption spectrometry (ICP-AES) of one sample of TB was carried out. For Dadhi Pariksha 50 grams of curd (pH - 3.5) was taken in petri dish and 500 mg of TB sample was kept in it and observed for 48 hrs. No discoloration surrounding the Bhasma area was considered as proper Bhasma [Figure 1], [Figure 2] and greenish bluish discoloration was considered as Apakwa (improper) [Figure 3]. Details of instrument used for XRD are as follows. Model - Rigaku Geigerflex, Manufacturer - Rigaku Denki Co. Ltd., Japan. [Diffractometer controller: MDI (Data Scan 3.2). Data Processing and Identification: MDIJADE 5.0 (Materials Data Inc., Livermore, California, USA)]. Instrument used for the PSD was Sympatec HELOS (H1004) SUCELL. Instrument used to perform quantitative elemental evaluation (ICP-AES) of the sample was - Inductive Coupled Plasma Spectrometer, Model: ARCOS from M/s. Spectro, Germany, R.F. Generator: Maximum of 1.6KW, 27.12 MHz.
| Results and Discussion|| |
The wire taken for the preparation of Bhasma quantitatively contained 99.87% w/w of copper which indicate the high purity of raw material. This copper wire is used for the purpose of electrical earthing and that's why it is in very pure form. Slight impurity in it decreases its electric conductivity. Hence these types of wires should be used as raw material for the preparation of TB. Generally copper wires in the market have coating over them to prevent formation of its oxide on the surface because copper tarnishes in moist air and converts to basic copper oxide (Cu 2 O).  But the wire taken in this study was not having any coating on its surface and therefore was subjected to the Shodhana process directly. After Samanya Shodhana the copper content was reduced to 90.84% w/w and further reduced to 90.20% w/w after Vishesha Shodhana whereas iron content was found increased from 0.11% w/w to 9.53% w/w after Samanya Shodhana and 6.84% w/w after Vishesha Shodhana [Table 1]. During red hot state copper is decomposed to cupric oxide (CuO) on its surface.  This increased conversion of copper into oxide leads to decrease in copper content after Shodhana procedure.  Since the iron ladle was used to perform the Shodhana procedure percentage of iron was found increased after the process because iron also reacts with atmospheric oxygen or steam when heated to red hot, to form ferroso-ferric oxide (Fe 3 O 4 ) and it may be possible that this oxide gets mixed with copper. 
|Table 1: Percentage of copper and iron after Samanya and Vishesha Shodhana of Tamra |
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Seven Puta were required for the preparation of proper Bhasma. As per the classical reference, the Bhasma should have been formed in three Puta only. But here Bhasma was not formed after three Puta (in curd test greenish bluish discoloration was observed within 30 minutes) [Figure 3]. So for moving further different Rasashastra texts were screened out regarding such a procedure of TB preparation. It was observed in many texts that next Puta should be given by adding equal amount of Gandhaka. Hence next four Puta were given by adding equal amount of Shuddha Gandhaka and triturating with Nimbu Swarasa.
According to the classics color of Tamra Bhasma is black.  Cupric oxide (CuO) and copper (I) sulfide (CuS) are black in color. , Therefore it can be inferred that TB is one of these or combination of both. , In some previous studies, XRD pattern of TB showed the presence of CuS whereas some showed the presence of Cu 2 S and Cu 7 S 4 . ,,,, In the process of TB preparation, copper is converted to its sulfide form in major since the sulfur is an accompaniment to the metal in the processing. During the heat treatment for multiple times (Puta), some sulfides may get converted to oxide. Because metallic sulfides when heated in air get converted to oxide of the metal and sulfur dioxide.  Therefore some oxides of copper are also found in the TB. Finally, it can be concluded that TB is the combination of sulfides and oxides of copper. Probable reaction can be given as follows where mercury (Hg) acts as a catalyst and sulfur (S) acts as a reducing agent.
Shodhita Tamra (Cu, CuO) + Kajjali (HgS, S) + Shuddha Gandhaka (S)Δ Tamra Bhasma [Sulfide (in major) and Oxide (in minor) of copper] + Mercury (Hg)↑ + Sulfur di oxide (SO 2 )↑
Many metal oxides are toxic; in comparison, a sulfide of a metal is generally less toxic compared to its oxide or chloride, being relatively less soluble in body fluids.  Ingesting cupric oxide (CuO) powder can result in a metallic taste, nausea, vomiting, and stomach pain.  In more severe cases, there may be blood in vomit or black or tarry stools, jaundice and enlarged liver. Blood cells rupture resulting in circulatory collapse and shock. These symptoms can be correlated with the different Dosha (ill effects) of Tamra Bhasma quoted in different classics. , So it can be inferred that Apakwa Bhasma or improperly prepared Bhasma is in CuO form and this may be harmful to the human body.
Organoleptically TB was black, soft, smooth, tasteless powder with no specific odor and no perceptible sound when chewed between the incisor teeth [Table 2]. TB complied with all the classical parameters. Various tests (Bhasma Pariksha) given in classical texts to check and confirm the quality of the Bhasma can be interpreted as given in [Table 3]. Importance to Dadhi Pariksha was given because it is the simpler chemical test to know the conversion of drug to a stable and safe/harmless form. This test was given due importance for finalizing the Bhasma because when Apakwa Bhasma is tasted, it produces excessive salivation, nausea, metallic taste, headache etc., So it is not advisable to taste the Bhasma after every Puta to finalize it. Varna (color) Pariksha (test) cannot be considered as final because black colored Bhasma may not be Awami (non-vomiting) in nature. On the contrary Dadhi Pariksha is very simple, safe, scientific in-house chemical test to finalize the TB.
Average values of physico chemical parameters of three TB samples were found identical with some of the previous studies , [Table 4].Very less value of loss on drying is indicative of almost absence of moisture in TB sample. High ash value in TB shows the presence of very high inorganic content. Lower value of the acid insoluble ash suggests the greater physiological availability of the drug.
Use of advanced analytical techniques is the highest need of time for the development of quality control parameters of Bhasma. Among them SEM is the technique which reveals the information of external morphology (texture), chemical composition, and crystalline structure and orientation of materials making up the sample.  High-resolution (2, 5, 10, 20 and 50 μm) images of TB sample at different magnifications (500 × to 8000 ×) showed the regular and uniform clusters of Bhasma particles and also clearly showed the particle size less than 2 μm [Figure 4] and [Figure 5].
For the identification of the compound/s present in the TB, XRD was carried out in which prominent peaks of cupric sulfide (CuS) were seen which confirms that final product is sulfide form of copper [Figure 6]. The particle size distribution (PSD) of a powder, or granular material, is a list of values or a mathematical function that defines the relative amounts of particles present, sorted according to size.  PSD is also known as grain size distribution and it can be important in understanding the physical and chemical properties of a material.  PSD analysis of TB showed volumetric mean diameter of 28.70 μm, particles of different sizes; 10% of the Bhasma material was below 2.83 μm size and 99% of the material was below 124.30 μm [Table 5] and [Figure 7]. Both these analyses (SEM and PSD) show the significant reduction of particle size in the Bhasma. This phenomenon allows the classical tests like Rekhapurnatwa, Varitaratwa, and Sukshmatwa etc., to develop. Attrition or milling is a typical 'top - down approach' in making nanoparticles which involves the breaking down of large pieces of material to generate the required nanostructures from them.  The process of preparation of Bhasma by following Shodhana and then Marana procedures is the ancient method of reducing the particle size up to the nano level. Some recent studiesof microstructure of different metallic Bhasma established that the Bhasma are nanoparticles. ,, When the particles change from centimeter size to nanometer size, the surface area and the surface energy increase seven orders of magnitude.  Due to high surface area these particles possess a huge surface energy and thus, become thermodynamically unstable or metastable.  This metastability (a long lived but not truly indefinite stability) can be the reason behind the longer shelf life of Bhasma. The decrease in particle size and increased surface area leads to enhanced dissolution rate which helps in rapid absorption of a drug.  This further increases the bioavailabilityof the drug.  Due to these factors (metastability, decreased particle size etc) potency of the Bhasmas increases resulting in decrease in their dose which eventually leads to reduction in dose related side effects. This could be the probable explanation for the Rasashastriya Bhasma being quicker in action and more potent even at lesser dose. 
|Table 5: Results of particle size distribution analysis of Tamra Bhasma sample |
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|Figure 6: X-ray diffraction image of Tamra Bhasma showing prominent peaks of CuS|
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One of the ten points' protocol suggested for the preparation of standard Bhasma suggests the physical standardization and elemental analysis of raw material and finished product.  On this ground ICP -AES carried out for the quantification of the elements present in the TB showed the presence of 56.42 wt % of copper and 23.06 wt% of sulfur. Small amount of iron was also traced in Bhasma [Table 6]. Sulfur was present in large proportion along with copper. This is because of its having been used as a calcination accompaniment to copper. Vyas N et al. also had the same observations in the elemental analysis of TB.  Heavy metals like cadmium, selenium were not detected. Arsenic, lead and mercury were present in traces. All this elemental composition makes the TB a blend of different macro and micro nutrients. The recent studies reported that the metallic Bhasmaare biologically produced nanoparticles and remain as multi-elemental cocktail. ,,,
| Conclusions|| |
All the classical parameters for the Bhasma have scientific background. Dadhi Pariksha is the simpler chemical method to check the genuineness of Tamra Bhasma. Chemically Tamra Bhasma is the sulfide form of copper (CuS) containing more amount of copper than sulfur along with other elements in traces. PSD analysis and SEM images show reduced particle size of the Bhasma which may facilitate absorption and assimilation of the drug into the body system. The observations in this study could be specified as the quality control parameters for Tamra Bhasma conforming to all the classical tests under the Bhasma Pariksha.
| Acknowledgements|| |
The authors would like to acknowledge SICART, VallabhVidyanagar for carrying out SEM and PSD analysis; and RSIC, IIT Bombay, Powai for carrying out ICP-AES.
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[Table 6], [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]