Non-Invasive Oxygen Determination in Intelligent Packaging Using a Smartphone

Abstract

Here, we present a technique for the determination AQ:1 AQ:2 1 of the gaseous oxygen concentration inside packed food. It is 2 based on the use of a luminescent membrane sensitive to O 2 that 3 is optically excited and read by a smartphone. The flash of the 4 smartphone along with an optical filter is used as the light source 5 for the optical stimulation of the membrane. The luminescence 6 generated, which is quenched by the surrounding gaseous oxygen, 7 is registered by the rear camera of the same device. The response 8 parameter is defined by combining the registered intensities at 9 two different wavelength ranges corresponding to the emission 10 and the absorption peaks of the sensitive membrane. Thanks to 11 this novel response parameter, the sensitivity is increased and, 12 more importantly, the thermal dependence of the membrane 13 is significantly reduced. This approach allows the use of a 14 luminescent O 2-sensitive membrane for intelligent packaging 15 with no need of any associated electronics for its excitation 16 and reading. This means that an oxygen sensor is developed, 17 where a luminescent compound acts as an indicator, therefore 18 combining the advantages of both schemes, that is, the simplicity 19 and reduced cost of indicators with the high sensitivity and 20 accuracy of selective sensors.

Sensing Exposure Time to Oxygen by Applying a Percolation-Induced Principle

“…Carbon dioxide, although released in ripening processes, is used as a replacement gas since it inhibits microbial growth (in e.g., fresh meat, fish, cheese) [18,19]. Monitoring the freshness of the food in the package is crucial and has been investigated extensively [13,17,[21][22][23][24][25][26][27][28][29][30][31]. In some approaches, food spoilage is indicated by released volatiles [28][29][30][31][32] (e.g., NH 3 for meat [30], CO 2 for grain [31] or C 2 H 4 for fruits [32]).…”

“…In some approaches, food spoilage is indicated by released volatiles [28][29][30][31][32] (e.g., NH 3 for meat [30], CO 2 for grain [31] or C 2 H 4 for fruits [32]). While sensing volatiles is rather specific for a given food, sensing oxygen is a more general approach [13,17,[21][22][23][24][25][26][27].…”

Flexible Strain and Temperature Sensing NFC Tag for Smart Food Packaging Applications

“…In most food packages, the presence of undesired gases could indicate the loss of quality and shelf-life of the food, as they originate from the oxidation of the content or the microbial growth [31]. While spoilage can take many forms, inflated or swollen food packages serve as the beacon of microbial contamination.…”

A review of smartphone point‐of‐care adapter design

“…Biological objects such as bacteria, 123 viruses, 124 and parasites 125 are in the micrometer to submicrometer range; therefore, magnification is mandatory for visual inspection of these objects. Smartphone adapters are employed here for visual inspection, measurement, recognition, 126 sensing, 127 and disease diagnosis [128][129][130] for conditions such as diabetes, cancer, 131 and malaria. 132,133 On the other hand, chemical agents, such as hormones, [134][135][136] biomarkers, 137,138 and reagents, 139 are essential for biochemical processes; therefore, smartphone adapters were neatly designed for sensing, measuring, and monitoring these agents, as shown in Figure 5.…”