Y. Serfor-Armah

MULTIELEMENTAL ANALYSIS OF SOME TRADITIONAL PLANT MEDICINES USED IN GHANA

ABSTRACT The essential elements in six traditional Ghanaian plant medicines used at the Center for Scientific Research into Plant Medicine (CSRPM), Mampong-Akwapim, Ghana, for the management and cure of various diseases were determined by Instrumental Neutron Activation Analysis (INAA), using thermal neutrons at a flux of 5 E 11 ns−1 cm−2. The plant medicines were: Ninga powder, Lippia tea, Ritchiea powder, Momordica powder, Kenken powder and Fefe powder. The samples were analysed without any chemical treatment. A total of seventeen elements namely Al, Br, Ca, Cl, Co, Cu, Cr, K, Mn, Mg, Na, Rb, Sb, Sc, Ta, V and Zn have been determined. Of these Sb and Sc were found to be present at the trace level, Br, Co, Cu, Cr, Mn, Rb, Ta, V and Zn at the minor level, while Al, Ca, Cl, K, Mg and Na were generally at the major level. The differences in the concentration of the elements may be attributed mainly to soil composition and the climate in which the plants grow. The method was validated by analysing the NIST Standard Reference Material (SRM-1571) and it was found that the elemental concentrations measured in the SRM-1571 were within ± 10%.

Application of instrumental neutron activation analysis to plant medicines in Ghana: A review

Some essential elements in eleven plant medicines used at the Center for Scientific Research into Plant Medicine (CSRPM), Mampong-Akwapim, Ghana, for the management and cure of various diseases were determined by instrumental neutron activation analysis (INAA), using thermal neutrons at a flux of 5.1011 n.s-1.cm-2. The plant medicines were: Sirappac powder-E, Tina-A powder, Blighia powder, Aphrodisiac powder, Ninga powder and Lippia tea. The others are Olax powder, Ritchiea powder, Momordica powder, Kenken and Fefe powder. Concentrations of seventeen elements namely Al, Br, Ca, Cl, Co, Cu, Cr, K, Mn, Mg, Na, Rb, Sb, Sc, Ta, V, and Zn have been determined by short, medium and long irradiation times. Of these elements Co, Sb, and Sc are found to be present at the trace level, Br, Cu, Cr, Mn, Rb, Ta, V and Zn at the minor level, while Al, Ca, Cl, K, Mg and Na were generally at major level. The differences in the concentration of the elements are attributed mainly to soil composition and climate in which the plants grow. Standard reference material NIST SRM-1571 (Orchard Leaf) was analyzed simultaneously with the samples. The precision and accuracy of the method were evaluated using real samples and the standard reference material. It was found that the elemental concentrations measured in the NIST SRM-1571 were within ±10% of the reported values. The importance of these elements as related to human health and nutrition has been discussed.

Simultaneous use of neutron transmission and reflection techniques for the classification of crude oil samples

Neutron attenuation and reflection characteristics of three crude mineral oil samples from West Africa were determined using 37 GBq 241Am-Be source in a single set-up and compared with those of paraffin (oil) and benzene, an aromatic compound. Based on the trends of measured data which are similar to those exhibited by paraffin but different from those associated with benzene, the crude oil samples could be classified as paraffinic. The total hydrogen content and weight ratios (O+C)/H and C/H determined for the crude oil samples using the transmission and reflection techniques are not only independent of the technique but are also consistent with literature values of thermal reflection technique.

Application of NAA standardization methods using a low power research reactor

Two widely used neutron activation analysis (NAA) standardization methods (relative and k0) have been validated at the Ghana Research Reactor-1 (GHARR-1) Centre using environmental and biological standard reference materials (SRMs). The samples were IAEA Soil-7 as an environmental sample, and NIST Orchard Leaves 1571 as a biological sample. The qualitative and quantitative analyses were done using a high resolution Canberra N-type high purity germanium (HPGe) detector. The accuracy and precision were evaluated for the elements analysed. The concentrations of most of the elements were found to be within 10% of the certified values. Precision was calculated from six replicate measurements and was found to be within 15%.

Epiboron instrumental neutron activation analysis for the determination of iodine in various salt samples

Epiboron instrumental neutron activation analysis (EINAA) using flexible boron as thermal neutron filter, has been used to analyze several salt samples obtained from various markets in Ghana for iodine. The method involves the irradiation of samples in boron carbide-lined polyethylene vials at the outer irradiation site of the Ghana Research Reactor-1 (GHARR-1). The samples were then counted directly without any pre-treatment on a Canberra N-type HPGe detector. The qualitative and quantitative analyses were done using the 443 keV photopeak of 128I. The precision and accuracy of the method have been evaluated and the detection limits of the various samples were calculated. The values of iodine determined in the iodized salt range between 10.0 and 210 ppm. For non-iodinated salts, iodine levels were below 500 ppb. The values obtained show great variations among the salt samples, sample collection time and from market to market. This results show that the method can be successfully applied in the determination of trace amount of iodine in salt samples without any chemical separation.

Predicting the yield of 177Lu radionuclide produced by the cyclic irradiation technique

The feasibility study on the production of (177)Lu radioisotope using a low power research reactor has been conducted. A reliable method for predicting the yield of (177)Lu produced using the cyclic activation technique based on the Westcott formalism has been established. A specific activity of 243.24 mCi/g was obtained when a (176)Lu(2)O(3) of natural abundance was irradiated for 4 h and decayed for 20 h for four cycles at GHARR-1 with a neutron flux of 5.0×10(11) ncm(-2)s(-1).

An alternative method for the measurement of thermal neutron flux (modified cadmium ratio method)

An alternative method of approach has been developed for the measurement of thermal neutron flux. The method depends only on the activity of the bare foil if the cadmium ratio at the irradiation position is known. The method has been tested on the GHARR-1 facility at the Ghana Atomic Energy Commission using gold and indium foils for the measurement of the thermal neutron flux in the flux range of 1010–1012 n·cm−2·s−1 and the results compare very well with those obtained using the conventional method (cadmium separation method).

Routine Monitoring of Market Infant Foods by Neutron Activation Analysis with a Low-Power Reactor

Abstract Instrumental neutron activation analysis technique with thermal and epithermal neutrons from a 30 kW research reactor has been used to determine the concentration of some essential elements in market infant foods. The elements Ca, Cl, Fe, Mn, Mg, K, Na, V, Zn, Br, and I were found in various proportions in four infant foods widely sold in Nigeria. A comparison of the measured results and producers quoted values indicates that the adopted experimental procedure can be used routinely for control and monitoring purposes.