Green Chemistry Synthesis of Nanostructured Zinc Oxide Powder Using Azadirachta indica Extract for Latent Fingermark Development

@#Introduction: Application of nano-engineered fingerprint dusting powders has been a recent trend to achieve latent fingermark development with superior ridge clarity. As such, efforts have been made to utilise natural resources to increase the sustainability of these emerging nano-engineered powders. Lithium-doped zinc oxide, primarily used as white pigments, have been previously applied to latent fingermarks with success. In the current study, nanostructured zinc oxide, synthesised using neem extract as the reducing agent, was evaluated for fingermark development on non-porous surfaces. Methods: The reduction of zinc nitrate hexahydrate was facilitated by neem extract, prepared by boiling neem leaves in distilled water. The thick yellow paste recovered was calcined in the furnace to produce a light yellow powder. Physicochemical composition of the powder was determined using microscopic and spectroscopic instruments. The effectiveness of the powder was tested on natural fingermark deposited on several non-porous surfaces. Results: Nanostructured zinc oxide with particle size ranging in between 1 to 3 µm consisting of highly aggregated spherical particle with less than 100 nm dimensions were synthesised. Developed fingermarks revealed excellent ridge details and contrast on dark coloured surfaces. Studying the fingermark closely under scanning electron microscope displayed selective distribution of particle on the ridges of the fingermark residue and very minimal deposition on the fingermark valleys. Conclusion: Nanostructured zinc oxide fabricated using green chemistry approach can be applied for the development of fingermark. Nevertheless, future works can be undertaken to enhance particle dispersity and to confer strong photoluminescence to the zinc oxide nanoparticles.

Morphological and Compositional Changes Exhibited by Rice Husk When Subjected to Synergistic Thermochemical Treatments

@#Introduction: Rice husk has portrayed great potential in becoming a sustainable biomass source in producing silica, cellulose and carbon materials, which garnered widespread interest among researchers. The objective of the current study is to determine the morphological and compositional changes in rice husk due to the synergistic effects of thermochemical treatment. Methods: Washed and dried rice husk was blended into a fine powder and then subjected to step-wise heat treatment and acid digestion to produce white ash. The intermittent products, as well as the original rice husk and the final ash product, were characterised using analytical instruments to document the morphological and chemical composition changes. Results: This report highlights the production of pure rice husk ash using a step-wise treatment using a combination of thermochemical treatment and carbonisation. The results showed that a partial breakdown of the lignocellulose components was achieved using directed thermal treatment at low temperature. The ionic impurities were leached out in subsequent heated acid treatment. Thereafter, the carbonaceous organic matter was completely converted to carbon during the carbonisation of the sample and the remaining carbon residue was removed during calcination. High purity ash contained agglomerated and nanostructured silica in the dimensions of 20 to 50 nm in the amorphous form. Conclusion: The step-wise treatment allowed systematic removal of each compound while maintaining the amorphous mineral phase of silica and avoiding carbon fixation. Understanding the effect of each treatment offers insight to produce purer silica from rice husk.

Detection methods of avian influenza - current and novel approaches

@# Avian influenza (AI), caused by the avian strain of influenza A virus (AIV) is one of the significant health concerns globally. Human infections with AI viruses were reported sporadically and often exhibited high mortality and morbidity rate. AI outbreaks also influenced the safety of the food supply and caused significant economic losses. Immediate control measures are required during AI outbreaks in poultry to prevent further viruses spreading. Hence, accurate, sensitive, and rapid detection methods are pivotal for decision making. Traditional methods of detection, such as virus isolation in embryonated chicken eggs, immuno-based methods, and nucleic acid amplification method, pose different limitations. These always grab the attention of researchers to improve existing methods or invent novel diagnostic approaches to compensate for the shortcoming of current methods applied. However, the method of choice is highly dependent on the availability of facilities and resources. Among the detection methods, reverse transcription-polymerase chain reaction (RT-PCR) is the most favourable method used for detecting AIV. However, a constant review of the virus genome is crucial to maintain the assay’s sensitivity. More comprehensive research and evaluation study are needed for new diagnostic approaches.