Silver doped hydroxyapatite coatings by sacrificial anode deposition under magnetic field.

Uniform distribution of silver (Ag) in the hydroxyapatite (HA) coated Ti surface has been a concern for which an attempt has been made to dope Ag in HA coating with and without magnetic field. Cathodic deposition technique was employed to coat Ag incorporated hydroxyapatite coating using a sacrificial silver anode method by using NdFeB bar magnets producing 12 Tesla magnetic field. While uniform deposition of Ag was observed in the coatings under magnetic field, dense coating was evident in the coating without magnetic field conditions. Uniformly distributed Ag incorporated HA in the present study has potential to fight microorganism while providing osseoconduction properties of the composite coating.

ED-XRF spectrometric analysis of comparative elemental composition of in vivo and in vitro roots of Andrographis paniculata (Burm.f.) Wall. ex Nees--a multi-medicinal herb.

The multi-elemental composition of in vitro--proliferated root tissues of Andrographis paniculata (Burm.f.) Wall. ex Nees was compared with that of the naturally grown in vivo plants. Trace elements namely Cr, Mn, Fe, Co, Ni, Cu, Zn, Se, Rb, Sr and Pb in addition to two macro-elements K and Ca were identified and quantified in root tissues of both sources using the energy dispersive X-ray fluorescence (ED-XRF) technique. ED-XRF analysis was performed using Mo K X-rays generated from a secondary molybdenum target. The elemental content of in vitro roots was found to be at par with that of naturally grown plants of the same species. This opens up a possibility of exploiting in vitro root cultures as a viable, alternative and renewable source of phytochemicals of relevance, besides providing a means for conservation of the valuable natural resources.

Trace element-based food value evaluation in soft and hard shelled mud crabs.

Concentrations of 10 elements were studied from the pre-moult hard shelled and newly moulted (soft shelled) crabs (Scylla serrata) by the (Energy Dispersive X-ray Fluorescence) EDXRF technique. The study evaluated the composition of all 10 elements from the body tissues and the exuvium of soft shelled and the carapace of pre-moulted hard-shelled crabs in order to evaluate the food value from nutritional and safety point of view for human consumption. The essential elements like K, Ca, Mn, Cu, etc., get reabsorbed from the carapace to the body tissues in order to meet the further requirement in the soft shelled crabs and are also utilized to some extent during the formation of new carapace, toxic element like Pb gets excreted during exuviation and element like Zn gets regulated, as and when become higher in bioavailable form. This study gives evidence that, the freshly moulted soft shelled crabs are more safe and nutritious than the hard-shelled crabs.

Elemental composition in mud crab Scylla serrata from Mahanadi estuary, India: in situ irradiation analysis by external PIXE.

During the present study concentration of nine elements (K, Ca, Mn, Fe, Cu, Zn, Se, Br and Pb) in different tissues of mud crab Scylla serrata from Mahanadi estuary, India were determined by the external PIXE set up at Institute of Physics, Bhubaneswar, India. The study demonstrates the effectiveness of the technique in analyzing both soft and hard tissue samples from marine organisms and opens the door for non-destructive, multi-elemental analysis of tissue samples with a very little sample preparation by direct irradiation. This technique can be well utilized for analyzing the tissue samples for environmental, toxicological and nutritional purposes. The study also demonstrates the elemental concentrations from tissue samples of any crustaceans from Mahanadi estuary for the first time. Sex based difference in the elemental concentration of the mud crabs were marked, which may be related to the growth rate and other biological activities. No significant difference in the concentration of elements (Ca, Mn, Fe, Cu and Zn) in the tissues of juveniles and adults of respective sex is observed, which indicated the active regulation of these elements by S. serrata.

Elemental analysis of aerosol samples collected from an industrial and a non-industrial town of Punjab (India) using PIXE technique.

Chemical composition of the aerosols is an important aspect of aerosol monitoring. The adverse effects on human heath due to different elements in aerosols depend on their concentrations. A comparative study of aerosol concentration and composition from an industrial town Mandi-Gobindgarh and a nearby (25 km away) non-industrial and comparatively less polluted town Morinda, in state Punjab (India) was carried out. Aerosol samples were analyzed by Particle Induced X-ray Emission (PIXE) technique at the Institute of Physics, Bhubaneshwar. Elemental concentrations were found to be much higher in Mandi-Gobindgarh as compared to Morinda. However, the large deviations from the mean concentrations, particularly in Mandi-Gobindgarh is suggestive of highly varying day to day industrial activity and changing weather conditions. Elements such as S, Br and Pb were found higher in the PM2.5 (particulate matter with = 2.5 microm aerodynamic diameter), which are related to burning of coal and oil in furnaces in Mandi-Gobindgarh. The elements related to natural dust such as K, Ca, Ti, Mn, and Fe are mainly distributed in PMcf (particulate matter with aerodynamic diameter between 2.5 and 10 microm) fraction in both the towns. High concentrations of Ti, Cr, Mn, Fe and Zn in the PMcf fraction from Mandi-Gobindgarh are likely due to the industrial activity of Steel rolling mills.