Introduction
Most biological processes require various minerals. Roughly more than 21 chemical elements are required for all processes that occur in the human biological system in varying quantities. In any of the essential minerals are deficient, different symptoms and body complications may arise, these include muscle defects, nervous system collapse and metabolic anomalies. In contrast, elements with poisonous properties are injurious to the body even at very low levels. Hence, it is very important to determine the concentration of various elements present in different drugs or food materials before releasing to the public. This is where elemental analysis becomes important.
The ingredients used in the manufacture of ayurdevic drugs are organic metallic compounds and biological materials that are removed from plants. There are diverse techniques that can be used to establish the makeup of compounds derived from plants. The techniques include “total reflection X-ray fluorescence spectrometry (TXRF), atomic absorption spectrometry (AAS), neutron activation analysis (NAA), and inductively coupled plasma mass spectrometry (ICP–MS)” (Al-Omari 2010). In addition, the application of a combination of radionuclide materials with energy dispersive X-ray fluorescence (EDXRF) illustrates a consistent identification of some elements.
For this study, improved detection limits were acquired using X-ray tubes. The objective of the experiment was to determine the elemental concentrations of ten ayurdevic drugs obtained from the neighboring markets. The drugs are used to remedy various diseases, however, these drugs may contain certain harmful elements or contain them at levels that can harm the human body. For this experiment, the determination of elemental levels was determined using the EXDRF technique (Al-Omari 2010).
The introductory part of the report is not exhaustive, especially in the techniques that can be used to determine the types of elements present in a compound. Other methods include the relatively recent Aerosol Mass Spectroscopy (AMS), atomic mass spectroscopy, chromatographic mass spectroscopy, and ion-mobility spectroscopy. besides, the author does not offer an explanation on the criteria for using the EDXRF procedure when there are many techniques that he could have used Rollins et al 2010).
Materials and Methods
The drug samples were then washed using distilled water and dried at room temperature. The final drying procedure was done in an oven at temperatures of 600 Celsius for approximately 20 hours before the analytic procedure began. Although the drying procedure took long, it was very important at ensuring that the elements present in the drugs were not destroyed. This stems from the fact that a faster drying procedure would have used high temperatures that could have caused the elements in the compound to react with other elements through processes such as oxidation, hydration or reduction. The long duration of the drying procedure also ensured that the samples became loose and very easy to crush (Al-Omari 2010).
After the 20-hour drying procedure, the samples were crushed to a fine powder and then sieved through a 75 µm mesh. The process was vital to achieving uniformity of samples since it is common knowledge that sample size affects the excitation volume. For the current experiment, roughly 5g of the dried samples were weighed and crushed to give small disc-shaped pellets with an average thickness and 27mm diameter. This process ensured that uniform samples were obtained.
The next procedure was sample irradiation and system calibration. The disc-shaped pellets were irradiated using an EDXRF analyzer to determine the distinguishing X-ray spectra. The spectrometer is fully automated and connected to a PC through the Minipal software. The Minipal analytical software was set to operate under different conditions before the analytical procedure begins. The samples were irradiated under three different conditions. The first one was set at a tube voltage of 4.09 kV, current set at 1000 µA, and devoid of the beam filter, this setting is suitable for the detection of elements with low atomic mass, such as Chlorine and Sodium. The second one was set at a tube voltage of 15kV using an aluminum filter. This is important for determining the elemental quantities from Calcium to Copper using K-lines and from Barium to Strontium using L-lines. The third condition was set at a tube voltage of 30kV and a current of 1mA. This final setting was important in determining elemental quantities from Calcium to Molybdenum using K-lines and elements through Barium to Uranium through the L-lines (Al-Omari 2010).
For the three conditions, standard peak graphs were used to detect the presence of Aluminum and Copper and were used to calibrate the machine. Since the accuracy of this calibration procedure was vital towards the success of the experiment, it was confirmed by the method of standard samples. The concentration of an element was determined using calibration equations to the total intensity of the suitable analyte. The Minipal software was used to obtain the XRF spectra of the samples. This was followed by a qualitative analysis to determine the identity of the elements present in the ten ayurdevic drug samples. The findings were found to be accurate by an analysis of the reference material. The results prove the accuracy of the procedure albeit with relative errors of ≤10%.
Results and Discussion
From the findings of the experiment, it was found out that the samples contained 19 different elements at varying concentrations. A comparison of these concentrations with the documented figure showed good accuracy and conformed to the standard rabge of ±10% with few exemptions. The accuracy of the procedure is attributed to the EDXRF analyzer’s ability to perform analyses at different settings, hence determining all the elements present at the various peak lines. However, the findings can be improved by performing more than one analysis on the same sample, and then finding the average of the concentration. This process could also help in detecting errors and eliminating outliers within data sets of a similar sample (Seinfield et at 2010).
From the findings, it was observed that certain drugs contained all the 19 elements at varying concentrations. However, Pottasium, Calcium, Iron, and Strontium were detected in all the samples and this was attributed to the fact the elements contain one or more medicinal components. It was also observed that the disparity in elemental concentrations of Silicon, Chlorine, Potassium, and Sulfur was much larger among the samples than other elements. The author does not provide an explanation for this anomaly, but it could have due to the fact that the elements had a single medicinal component, hence, certain elements had low levels of certain medicinal components while some had higher concentrations, this affected the levels of the components.
Elemental Analysis
Iron was discovered in all drug samples. Drug S5 had the highest concentration while S6 had the lowest level. The recommended daily intake of Iron is 10-18 mg. Accordingly, for drug S5, a DALLA quantity of 1.6-3 g is permissible. Because the daily dosage of S5 is 130-250 mg, the drug was taken to be safe for human use. Using a similar procedure, drug samples S4 and S2 were also found safe. Instructions on respective packages show that drugs S5, 54, and S3 are used to treat anemic conditions and this is evidenced by their higher concentrations of Iron which are in conformity with the RDA daily intake recommendations. For S5 drug, the authors conclude that the high Iron concentrations is attributed to its natural presence in the compounds used in the manufacture of the drugs, rather than an additive, or ingredient.
The author’s assumption that Iron originated from the materials used to manufacture the drugs could have been a misleading notion as manufacturers can add Iron to the drug samples in order to attain the minimum levels for the concentration of Iron.
Calcium was also found to be present in high concentrations in drug samples S1, S2 and S9: the concentration was higher than 10,000ng/kg. The high concentrations of Calcium was attributed to the element’s neuromuscular systemic improvement characteristics. Calcium also aids in bone development, cardiac roles, hormonal response, and blood clotting. The high concentrations of the element in S2 was linked to the treatment of constipation and anemia, for which it was said to treat. Chromium was detected in high concentrations in sample S2, and an analysis similar to that of Iron showed that its concentrations were safe for human use. The rest of the samples had little or no concentrations of Cr. Manganese was not present in all samples except sample S4, and this was attributed to its toxicity at high levels, therefore, care should be taken while using the drug. Trace concentrations of the element is vital in carbohydrate metabolism and bone growth.
The rest of the elements were found to be present in the samples at varying concentrations, and all of these concentrations were found to be safe for human use.
Conclusion
The concentration of 19 elements was determined in ayurdevic drugs using a technique using the EDXRF technique. The disparity in concentrations was found to differ among all the samples, from 0- 149827 mg/kg. An association was observed between the concentrations of Iron and Calcium, this can be attributed that both elements are important in several biological processes in the human body, and a deficiency of any of any of the compounds can adversely affect one’s health. The concentration of Mercury was found to be low, owing to its toxicity. The accuracy of the experiment is commendable as the findings corresponded with the documented element concentrations. This shows that the EDXRF technique is accurate for analysis of elements present in small or high concentrations. In order to improve the accuracy of findings, future studies should use other techniques to prevent method errors. Besides, the samples used should be handled in a clean environment since even the least concentration of elements in water used to clean the samples can cause substantial errors.
References
Al-Omari, S. (2010). Determination of essential and toxic trace elements in ten herbalmedicines using energy-dispersive XRF analysis. X-Ray Spectrom, 40, 31–36.
Rollins, A. W. et al. (2010). Elemental analysis of aerosol organic nitrates with electron ionization high-resolution mass spectrometry. Atmospheric Measurement Techniques, 3, 301–310.
Seinfield, J. H. et al. (2010). Elemental analysis of chamber organic aerosol using an aerodyne high-resolution aerosol mass spectrometer. Atmos. Chem. Phys., 10, 4111–4131.