Journal of Ayurveda and Integrated Medical Sciences

Introduction

Svarnamakshika Bhasma (SMB) is an Ayurvedic medicinal preparation widely used by Ayurvedic practitioners. Svarnamakshika is defined as a Copper ore containing Chalcopyrite (CuFeS2) mineral in Ayurvedic Pharmacopeia of India (API) Part I, Vol VII.^[1] Chalcopyrite is a Copper Iron Sulfide, the most abundant Copper ore. Copper, Iron and Sulphur are the three major elements found in Chaclopyrite. API prescribes 5%, 20% and 12% as minimum contents of Copper, Iron and Sulphur respectively, in Svarnamakshika (chalcopyrite) as quality standard.^[1]

A processed Svarnamakshika (chalcopyrite) referred as Sandrita Svarnamakshika (Copper concentrate), defined as fine powder of Copper concentrate, in which minimum content Copper 12%, Iron 23% and Sulphur 28% has been set in API.^[2]

Sandrcta Svarnamakshika (Copper concentrate) retains overall minerology and other properties after processing the source mineral Svarnamakshika (chalcopyrite). The only difference is increase in its Copper content to more than 12%. Both Svarnamakshika (chalcopyrite) and Svarnamakshika Sandrita (Copper concentrate) can be used to prepare Svarnamakshika Bhasma (SMB) as per API. However, many research scholars have reported much higher content of Copper, Iron and Sulphur in Chalcopyrite found in mines across the globe. According to Haldar SK^[3] Chalcopyrite is a Copper-Iron Sulfide mineral which in the purest form contains 34.5% Cu, 30.5% Fe, and 35.0% S. Shuming Wen et al^[4] have reported high purity Chalcopyrite from Copper mine in China. On analysis, it was found to contain Copper 33.24%, Iron 27.22% and Sulphur 34.81%.

Three samples of Chalcopyrite obtained from Chambishi Copper Mine of Zambia, Hunan Province ofChina and Guangxi Province of China, were analysed by Hongbo Zhao et al.^[5] XRD analysis of these three samples indicated Copper content as 35.8%, 31.9% and 30.1% respectively. Whereas, Iron content was 27.3%, 26.9% and 26.7%. Their Sulphur content was 29.4%, 28.6% and 27.6% respectively. Copper, Iron and Sulphur content in purest form of Chalcopyrite as reported by different research scholars as against their content prescribed in API is shown in Table 1.

Materials and Methods

Seven samples of Svaranamakshika Bhasma comprising five marketed and two prepared by research scholars, were collected for this study. In addition, two samples claimed to be Svarnamakshika used by the researchers to prepare Svarnamakshika Bhasma were also collected. All the samples were subjected to XRF and XRD analysis with an object of assessing product uniformity of Svarnamakshika Bhasma with respect to chemical composition.

X Ray Fluorescence Analyser

Vanta handheld X Ray Fluorescence Analyzer was used for XRF analysis in this study. It is an energy dispersive X-ray fluorescence spectrophotometer used to perform identification and analysis of elements contained in the test sample. This method identifies the elements in a substance and quantifies them. An element is defined by its characteristic X-ray emission energy (E). The amount of element present is determined by measuring the intensity of its characteristic line. In XRF spectrometry, primary X-ray photons are emitted from a (source) X-ray tube and strike the sample. These primary photons knock electrons out of the innermost orbitals vacating a space. An electron from outer orbital moving into this vacant space in the inner orbit, emits an energy known as secondary X-ray photon. The secondary X-ray photon is characteristic of a specific element.

Method

The sample powder filled in the sleeved sample cup covered with film was subjected to XRF analysis using Vanta XRF analyser. Positioning the measurement window of the analyser directly over the surface of the film, the test was initiated. The results displayed on the analyser screen were recorded at the completion of the test.

X Ray Diffraction

XRD analysis is a non-destructive analytical technique. A monochromatic X-ray beam is used to irradiate a sample in this technique.The X-ray source and detector are positioned at variable angles around the sample, which is usually flat.X-ray diffractogram obtained in the analysis is used to identify the crystallographic structure and chemical composition of the sample.

XRD Analysis

Figure 1: X- Ray Diffractograms of seven samples of Svarnamakhika Bhasma (SMB)

Elements detected in XRF analysis were used as the basis for finding out presence of their compounds in the XRD analysis. Complex compounds especially Oxides and Sulfates of Iron, Copper and light elements like Sodium, Potassium and Calcium were detected in almost all samples of Svarnamakshika Bhasma (SMB). (Fig 1 and Table 3 to 6).

Oxides

Iron oxide Fe2O3 was observed to be the principal compound in all the samples of Svarnamakshika Bhasma (SMB) except in SMB-BDT. However, Iron Oxide Acetate Hydroxide Hydrate Fe2 O6! C2 H6 H2 O was detected in it (Figure 1, Table 4). Other variants of oxide of Iron like Gamma Iron oxide (Fe21.333 O32) and Iron oxide Hydroxide (Fe H O2) were detected respectively in SMB-KNG (Figure 1 Table 4) and SMB-ADT (Figure 1, Table 6). Presence of Calcium Iron Oxide (Ca2 Fe O3.5) was observed in SMB – DTP. (Figure 2, Table 5).

Sulfates

Sulphur is a major content of Svarnamakshika (chalcopyrite). Sulfates of Iron like Iron Sulfate Hydrate (Fe SO4 (H2 O)), Fe2 (SO4 )3 (H2O)9 and Iron Hydrogen Sulfate Hydrate (Fe2 H6 O18 S4) were found present in SMB-BDT (Table 4).

Raw Svarnamakshika and Svarnamakshika Bhasma

Table 7: Element content in Raw Svarnamakshika (RSM) and Svarnamakshika Bhasma (SMB)

XRD Analysis of Raw Svarnamakshika

Figure 2: X Ray Diffractogram of Raw Svarnamakshika (RSM- BTR ) and Svarnamakshika Bhasma (SMB- BTR)

Figure 3: Compounds detected in XRD of Raw Svarnamakshika RSM- ADT and Svarnamakshika Bhasma (SMB- ADT)

Two samples of raw Svarnamakshika were analysed in this study. Both these samples were collected from the research scholars. None of the two complied with the API prescribed quality standard of Copper and Sulphur content. RSM-ADT contained 3.844% copper. Whereas Copper content in RSM-BTR was a meagre 349 ppm.

Iron, Copper and Sulphur are the three major elements present in Svarnamakshika (chalcopyrite). Minimum quantities of these three elements necessary to be present in the Svarnamakshika (chalcopyrite), are prescribed as Pharmacopeial quality standard in the API monograph.^[1] Interestingly, the minimum content of Copper, Iron and Sulphur in Svarnamakshika (chalcopyrite), prescribed in API is much lower as compared to the contents of these elements in high purity chalcopyrite as reported by various research scholars^[3.4.5] (Table 1). The present study was designed to determine the quantities of these three elements in the Svarnamakshika used to prepare the Svarnamakshika Bhasma (SMB).

XRF Analysis

Iron content in the two samples of raw Svaranamakshika (RSM) collected from the research scholars was 41% (RSM -BTR) and 33.21% (RSM- ADT) (Table 7). In this regard, both these samples comply with prescribed API pharmacopeial standard of not less than 20% (Table 7). However, the two samples failed to comply with Copper content of not less than 5% as prescribed by API. Copper content of RSM- ADT was 3.844%. Whereas, Copper was almost absent (140 ppm) in Svarnamakshika (RSM-BTR) (Table 7). It clearly indicates that RSM-BTR is not the Svarnamakshika (chalcopyrite) as defined in the monograph in API. The sample RSM-ADT also failed to qualify the standard of Sulphur content. Thus, although RSM-ADT did contain Iron, Copper and Sulphur, the Copper and Sulphur content in it was much below the requirement of API standard.

The XRF analysis of Svarnamakshika Bhasma (SMB) showed that Copper is present in only one marketed sample (SMB-DTP- 16.08%.) (Table 2) and in one sample collected from research scholar (SMB-ADT – 3.521%) (Table 7). Copper content in other samples of SMB was in ppm measure. The observation indicates that only one marketed sample of Svarnamakshika Bhasma - SMB- DTP was likely to be prepared from Svarnamakshika (chalcopyrite) complying with the API prescribed pharmacopeial standard with respect to Copper content. Whereas no other marketed samples tested in the present study appeared prepared from Svarnamakshika (chalcopyrite) as defined in the API monograph. Wide variation in Iron content in the samples of Svarnamakshika Bhasma (SMB) was observed in this study.

Apart from these elements, Aluminium (Al), Calcium (Ca) and Silica (Si) were also detected in minor quantities in almost all the samples of SMB. (Table 2). The study indicates that although highly pure Chalcopyrite is rich in Copper and Iron content, it is not used by any manufacturer to prepare Svarnamakhsika Bhasma.

Use of Chalcopyrite much lower in Copper and Iron content is permitted by API, a legal document mandatory to be followed by manufacturers of Ayurvedic Medicine in India. Basically Svarnamakshika (chalcopyrite) being a mineral, is composed of complex compounds.

The major element Copper, along with Sodium, Potassium, Calcium, and Ammonium combining with Sulphur form their complex Sulfides and Sulfates as a result of speciation. Such complex compounds are also found in Svarnamakshika Bhasma.

XRD Analysis

XRD analysis is the most important analysis in determining the chemical composition of Bhasma preparations. In the present study, XRD analysis revealed the complex chemical composition of Svarnamakshika Bhasma, which differed widely from sample to sample. Iron oxide (Fe2O3) was observed present in all the samples of Svarnamakshika Bhasma except in one sample (SMB- BDT). Presence of Fe2O3 in Svarnamakshika Bhasma has been reported by different workers in the past. Nair RR et al^[10] have reported Fe2O3- 75.54% during XRF analysis in their study. Bharadwaj R et al^[7] and Mohapatra and Jha^[8] also report presence of Fe2O3 in Svarnamakshika Bhasma analysed by them.

Apart from Fe2O3 other forms of oxides of Iron have been detected in Svarnamakshika Bhasma in the present study. In SMB-ADT Iron oxide hydroxide (Fe2O6 C2H6 H2O) (Table 6) was found present. In SMB-DTP along with Iron oxide, Calcium Iron oxide (Ca2 FeO3.5) was also detected (Table 5).

In addition to oxides, various Sulfate compounds like Sulfate of Iron, Iron and Potassium, Iron and Sodium, and Iron and Copper; were detected in different tested samples of Svarnamakshika Bhasma. Iron Sulfate Hydrate (FeSO4 (H2O)4) and Iron Hydrogen Sulfate Hydrate (Fe2 H6 O18 S4) were found present in one sample SMB-BDT (Table 4).

XRD analysis of the samples analysed in this study indicates that Svarnamakshika, a mineral, is composed of complex chemical compounds made of Iron, and when present of Copper as well. Both these metals form various compounds combining with Calcium, Potassium, Sodium, Ammonium, the elements found naturally mixed with almost all the minerals due to speciation. Copper compounds could be detected in only one marketed sample SMB-DTP in this study. Whereas, Iron oxide (Fe2O3) was found present in all the samples. The observation indicates that with exception of one manufacturer all other manufacturers whose Svarnamakhsika Bhasma was analysed in this study, do not use Svarnamakshika (chaclopyrite) as prescribed by API for manufacturing Svarnamakshika Bhasma. It is observed in this study that Ayurvedic Bhasma preparations are neither single chemical entities nor simple chemical compounds. They are all mixtures of complex chemical compounds. Apart from the chemical compounds of the main source metal, compounds of elements like Calcium, Sodium, Potassium, naturally found in minerals are also present in the Bhasma preparations.

This study has also raised a question regarding the quality of Ayurvedic Bhasma preparations sold in the market. The five marketed samples of Svarnamakshika Bhasma analysed in this study varied widely from each other in their chemical composition. Pharmacological action of a drug is closely dependent on its chemical composition. Uniformity in chemical composition of drug products produced in multiple batches is essential to ensure uniformity in their pharmacological action. Such uniformity appears completely missing in the five marketed samples of Svarnamakshika Bhasma analysed in this study. Absence of this uniformity is observed as a result of use raw Svarnamakshika not complying with pharmacopeial standards prescribed by API.

Conclusion

Overall study indicates absence of uniformity in the marketed samples of Svarnamakhika Bhasma analysed in this study. Wide variation in chemical composition in the samples of Svarnamakshika Bhasma tested in this study with respect to individual elements and chemical compounds, was observed.

5. Zhao H, Yang C, Zhang X, Zhang Y, Qiu G. Dissolution and passivation mechanism of chalcopyrite in bioleaching. In: Biohydrometallurgy of Chalcopyrite. 2021: 125-156. Available at: https://doi.org/10.1016/B978-0-12-821880-8.00006-3

6. Drugs and Cosmetics Rules 1945. Govt. of India, Ministry of Health & Family Welfare, Dept of Health, as amended up to 31st December 2016.

7. Bhardwaj R, Johar S, Kapila A, Sharma A. Physicochemical Study and Quantitative Analysis of Swarnamakshika Bhasma. Int J Pharm Biol Sci Archive (IJPBA). 2021;9(1):7-15. DOI: https://doi.org/10.32553/ijpba.v9i1.172

8. Mohapatra S, Jha CB. Analytical study of raw Swarna Makshika (Chalcopyrite) and its Bhasma through TEM and EDAX. AYU. 2013;34(2):204-208. DOI: 10.4103/0974-8520.119682

9. Nambiar S, Kadibagil VR, Hussain G. Physicochemical Analysis of Swarnamakshika Bhasma Prepared by Two Different Methods. Annals of Ayurvedic Medicine. 2019;8(3-4):94-103.

10. Nair RR, Lakshmi ST. Preparation and Physicochemical Characterisation of Swarna Makshika Bhasma. Int J Ayurveda Pharma Res. 2018;6(11):48-54.