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A rapid immuno strip test was developed to provide visual detection of pork adulteration in processed meats. Gold nanoparticles was prepared and conjugated with anti-Swine IgG polyclonal antibody. A lateral flow immunosensor was developed, and then were used to test pork adulterated in processed meats, i.e. beef meatball samples. The simulated samples consisted of pork-in-beef meatball at the ratio of 0–100 (%w/w) adulteration levels that were extracted in phosphate-buffered solution. Pure beef meatball without pork was included as controls. The response time was completed in 5min, after incubation time. Detection limit of the immunosensor strip was 0.1% (w/w). This immunosensor tests can be applied to detect low levels of pork adulteration in beef meatballs. The reliability of the assay was further investigated by comparing the results to those of commercially available ELISA kits. It was obtained that the correlation of two methods was excellent. Thus, the strip could provide a simple approach to detect pork adulteration in processed meats samples with high reliability.

Spectrophotometric determination of hydroxymethylfurfural (HMF) based on p-toluidine as a reagent has been studied. The absorption intensities were measured at a wavelength range of 250 to 500 nm to record the absorption spectra before and after reaction with the HMF. The solution response was obtained at pH 3. The concentration of HMF was 5 × 10-3 M, whereas for p-toluidine was 8 × 10-3 M .The relative standard deviation (R.S.D.) of reproducibility was 3.33% when concentration of p-toluidine 3 × 10-3 M was used .The photostability was found to be good with 1.9 %. M was used . The photostability was found to be good with 1.9 %.

In Malaysia, more than 50,000 tons of used automobile tyres are stockpiled annually. This subsequently causes a major threat to the environment. This article focus on the durability of mortar with treated crumb rubber (TCR) as partial replacement for fine aggregate (FA) and addition of oil palm fruit fibre (OPFF) in the mix. For every 0.5% OPFF additions, there were 10% TCR replacements up to 30%, resulting in 16 different mixes with constant water cement ratio. The specimens were cured either by water ponding or water sprinkling for 28 days, after which they were preconditioned and subsequent carbonation depth measurement was made. The results showed that the carbonation depth lies between 2.5mm to 6.7mm. These confirmed that rubberised fibre mortar achieved carbonation depth of less than 15mm, the tolerable limit.

The use of chemometrics to analyse near infrared (NIR) spectra to determine pork adulteration in beef meatball was developed. Since, the adulteration of pork in beef meatball is frequently occurring. This study was aimed to develop a fast and simple technique for the determination and quantification of pork adulteration in beef meatball using NIR spectra and chemometrics. Both partial least-squares (PLS) calibration and linear discriminant analysis (LDA) model were developed to determine pork adulteration in beef meatballs. The models using the first derivative spectra, accurately classified 100 % of the pork adulterated beef meatballs samples using training set and test set. The PLS and LDA models were subsequently used for the determination of pork adulteration in real beef meatball samples. The results showed that the PLS and LDA models developed were in good agreement with the immunochromatographic method. Therefore, the potential of NIR spectra and chemometrics as a rapid method for halal authentication and identification of pork adulteration in beef meatball have been successfully developed.

This paper reports the results for the quantitative determination of ammonia (NH3) in aqueous solution by a UV-vis spectrophotometric method and artificial neural network (ANN) intelligence tool. Quantitation of NH3was based on the chemical reaction of NH3with cobalt(ii) (Co2+) ions in basic medium to form a blue hexamminecobaltate(ii) ([Co(NH3)6]2+) complex. Characterizations of Co2+ion in solution included photostability, pH effect, response time, Co2+ion concentration effect, dynamic linear range and reproducibility, which were performed using a UV-vis spectrophotometer. The pink cobalt species gradually changed to blue with increasing NH3concentration. The absorption calibration curve was linear over the NH3concentration range of 0.6–3.5 mM at optimum pH 8 with a reproducibility relative standard deviation (RSD) of <4.0%. The interference effect was found to be negligible for a number of foreign ions present in the reaction medium during NH3determination in an aqueous environment. A set of absorbance data for the [Co(NH3)6]2+complex at selected wavelengths was input for ANN training using a back-propagation algorithm. The trained network with 22 hidden neurons, a 28 500 epoch number and 0.001% learning rate has extended the dynamic NH3concentration range to 0.6–5.9 mM with a calibration error as low as 0.0649 × 10−3. The proposed ANN electronic sensor shows promise for NH3estimation in unknown water samples based on pattern recognition.

1,2-bis-(N’-benzoylthioureido)cyclohexane (BTCH), C22H24N4O2S2, was successfully synthesized, characterized by infrared and NMR spectroscopic techniques and supported by X-ray structural studies. The compound was tested for the fabrication of a potentiometric sensor for Hg2+metal ions. The sensor based on photocurable self-plasticizing poly(n–butylacrylate) membrane with immobilized BTCH as ionophore exhibits linear response in a Nernstian manner within the concentration range of 10-5- 0.1M mercury ions. The sensor displays low detection limit with response time between 50 - 100seconds. The electrode reveals a good selectivity for mercury ion over several other tested cations.

Electrochemical biosensors for phenolic compound determination were developed by immobilization of tyrosinase enzyme in a series of methacrylic-acrylic based biosensor membranes deposited directly using a photocuring method. By modifying the hydrophilicity of the membranes using different proportions of 2-hydroxyethyl methacrylate (HEMA) and butyl acrylate (nBA), we developed biosensor membranes of different hydrophilic characters. The differences in hydrophilicity of these membranes led to changes in the sensitivity of the biosensors towards different phenolic compounds. In general biosensors constructed from the methacrylic-acrylic based membranes showed the poorest response to catechol relative to other phenolic compounds, which is in contrast to many other biosensors based on tyrosinase. The decrease in hydrophilicity of the membrane also allowed better selectivity towards chlorophenols. However, phenol biosensors constructed from the more hydrophilic membrane materials demonstrated better analytical performance towards phenol compared with those made from less hydrophilic ones. For the detection of phenols, these biosensors with different membranes gave detection limits of 0.13 – 0.25 μM and linear response range from 6.2 – 54.2 μM phenol. The phenol biosensors also showed good phenol recovery from landfill leachate samples (82 – 117%).