Array of MIP-Based Sensor for Fruit Maturity Assessment

Traditionally, fruits are harvested through conventional methods which are based on smell, texture and harvesting time. This analytical technique has many disadvantages in terms of objectivity and subjectivity. By determining various fruits volatile released during pre-matured until matured period, one can actually selectively establish the exact time of a fruit to ripe. The aromatic volatile compounds emitted by Harumanis mango were analyzed using GCMS and found that terpenes hydrocarbon e.g. limonene, α-pinene, β-pinene, α-terpinene, γ-terpinene and 3-carene are the major volatiles that released by the ripe mango. In this work, MIP (Molecularly Imprint Polymer) based sensor array were fabricated and tuned to mango aroma volatiles. HyperChem software simulation is used to obtain key information such as the Binding Energy (ΔE) between the template and the functional monomer that lead to the stable MIP. Designing the MIP using HyperChem is an advantage into saving time and cost compare to trial and error experimental methods. Array of different MIPs template e.g. limonene, α-pinene and β-pinene were synthesis and coated onto the surface of QCMs (Quartz Crystal Microbalance) followed by polymerization and removal of templates molecules that will leave the cavity of selective templates. These QCM arrays are able to distinguish between different terpenes gases released by maturity and ripeness mango due to its selectivity and sensitivity properties of sensor response. The findings of this study is a great breakthrough for the agricultural sector as volatile sensing of chemical markers could determine the optimal harvest time of the local fruits and ensuring the quality and standards.