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Surface plasmon resonance (SPR) based biosensor is a gold standard optical sensor for biological protein interaction in life science. In this paper, we firstly discuss how the SPR based sensor can give unique advantages over other sensing techniques for food safety and food quality control in food industry. We discuss the differences in sample preparation process for the SPR system and other screening methods and point out that the SPR can reduce the food screen quality control cost and time. A brief review of food analysis that has been tested under SPR system. Key requirements for building up a surface plasmon resonance based sensor for food industry especially in Thailand are highlighted. An SPR based sensor has been recently developed and constructed based on the requirements. We also discuss practical issues and how to possibly get around them.

Hydrazine hydrate is a highly toxic chemical widely used in agricultural and pharmaceutical industries. Exposure to hydrazine can induce an irritation of respiratory tract, blindness, damage of the DNA and central nervous system. In this paper, we will show the hydrazine hydrate (N2H4) detection using fluorescence carbon nanodots synthesized from mandarin rind, the so-called R-CNDs. Highly sensitive detection can be seen by naked eyes in a fluorescence red-shifting and by analyzing absorption spectra in case of micromolar concentrations of hydrazine hydrate solution.

The dielectric permittivity (ε) of Y2NiMnO6 ceramics prepared by sintering at 1400 °C over 6 to 24 hours was investigated. The response of the ceramics was measured from 1 kHz to 3 MHz, with the influence of a fixed dc bias from 0 to 1.5 V and temperature from 40 °C to -60 oC. Increasing dc bias was found to reduce ε' at low frequencies, while at higher frequencies the dc bias had less influence on ε'. At 40 °C a sharp transition from high to low ε' occurred starting at ~100 kHz, as the temperature of the ceramic was lowered, the transition shifted to lower frequencies. This behaviour is attributed to the charge ordering of Ni2+ and Mn4+ ions and the thermal effect on the ions energy.

Microscope add-on toolkits for smartphone and tablet have become more widely available in the market. Although, these are sufficient to meet the demand and requirements of standard users, e.g. educational usage, these devices, in fact, do not meet the medical and biological requirements where fluorescence imaging plays a crucial role. In this paper, we introduce our innovative design in compact fluorescence microscope for smartphone and tablet. The device enables users to take fluorescent images at several excitation wavelengths using compact sources and filters.