Smart Tags Research Articles

Molecular Spies in Action: Genetically Encoded Fluorescent Biosensors Light up Cellular Signals.

Cellular function is controlled through intricate networks of signals, which lead to the myriad pathways governing cell fate. Fluorescent biosensors have enabled the study of these signaling pathways in living systems across temporal and spatial scales. Over the years there has been an explosion in the number of fluorescent biosensors, as they have become available for numerous targets, utilized across spectral space, and suited for various imaging techniques. To guide users through this extensive biosensor landscape, we discuss critical aspects of fluorescent proteins for consideration in biosensor development, smart tagging strategies, and the historical and recent biosensors of various types, grouped by target, and with a focus on the design and recent applications of these sensors in living systems.

Starch-pectin smart tag containing purple carrot peel anthocyanins as a potential indicator of analogous meat freshness

Smart films of starch/pectin and purple carrot peel (PCP) containing anthocyanins were developed, characterized, and used as pH-responsive tags to monitor plant-based chicken analogous. This study innovates by incorporating PCP in the film solution both as an extract and as a powder, and the resulting tags were applied to a plant-based food. PCP powder <100-mesh was directly incorporated into the film-forming suspension. For powder >100-mesh, two extracts were tested: an aqueous solution and a 1 % NADES solution added to the film-forming suspension. Quantification of PCP anthocyanins by HPLC showed a higher extraction under acidic conditions (1664 mg C3G equivalents 100 g−1). Films with PCP presented greater light protection. Films with 15 % and 25 % PCP and those with added extract showed better tensile strength (3.0–3.6 MPa), elongation at break (16–20 %) and a water contact angle of 52°. All films responded to pH variations (1 to 14) and ammonia vapor and showed ΔE* values >5. After 3 days, films used as smart tags monitoring chicken analogous presented noticeable color differences for PCPNADES (55 ± 8) and 15%PCP (40 ± 1). PCP showed strong potential as a pigmenting agent in films, especially as an aqueous extract with NADES for use as pH-responsive tags in chicken analogous.

An overview of technological challenges in implementing the digital product passport in the textile and clothing industry

Abstract The textile and clothing industry is undergoing a shift towards a circular business model, driven by new European Commission regulations, which mandates that by 2030, textile products available on the European Union (EU) market must be recyclable and sustainable. To facilitate data collection, storage, and sharing throughout the entire product lifecycle and ensure product traceability and sustainability, the use of Digital Product Passports (DPPs) will be required. This article presents an analysis of the most commonly known digital data technologies from the perspective of their use in digital garment labelling, describing their advantages and limitations. The analysis is complemented by practical insights gathered from semi-structured interviews with garment producers in the Baltic Sea region. The survey revealed that producers prioritise sustainability and are prepared to digitise product information but are awaiting EU’s clear guidance. Despite the challenges posed by DPP implementation from the global, producer, and customer perspectives, upcoming regulations are seen as providing new competitive opportunities for products and services. Both the technology analysis and the expert survey indicate that QR (quick response)-based smart tags are potentially the most straightforward solution for the initial phase of DPP implementation.

A Highly CO2-Sensitive Wood-Based Smart Tag for Strawberry Freshness Monitoring.

Smart tags are used for monitoring the freshness of foods. However, they often lack significant color changes, and their accuracy needs to be improved. In this study, a poplar veneer with a natural pore structure was selected as a matrix to prepare a smart tag with high pH sensitivity for tracking the freshness of strawberries. The delignified veneer was modified using 2,3-epoxypropyltrimethylammonium chloride (EPTAC) to be given positive charges to adsorb bromothymol blue (BTB) through electrostatic interactions. The adsorption capacity of the veneer reached 7.0 mg/g at 50 °C for 4 h, and the veneer showed an obvious blue color. The smart tags exhibited distinct color changes at different pHs and showed quick color changes in response to acetic acid. As the freshness of strawberries decreased, the color of the smart tags changed from blue to yellow-green, which indicated that the accuracy was high. In this study, an effective method was fabricated to prepare a highly sensitive tag, promoting popular application to ensure food quality.

Novel copper-based metal–organic skeleton smart tags that respond to ammonia for real-time visual freshness monitoring of shrimp

In recent years, an amount of attention has been paid to natural pigment-based pH/ammonia-responsive colorimetric smart labels in the field of real-time visual food freshness monitoring. However, the drawbacks of natural pigments, such as complicated extraction processes, poor photostability, and easy inactivation, have severely limited their application in smart packaging. In this research, natural pigments were replaced with copper-based metal–organic frameworks (Cu-MOF) to serve as ammonia-responsive indicators. It attained the benefits of excellent mechanical qualities, high photostability, and greenness. The changes of ΔE values of the smart label composite films of starch/polyvinyl alcohol (PVA)/Cu-MOF were less than 4.8 after being placed in a constant temperature and humidity environment for 40 d, indicating that they have excellent color stability. Within an atmosphere of 0.8 mM ammonia, the composite film can produce a significant color change from teal green to deep blue in 1 min, indicating that the film has ammonia sensitivity. The composite film, in addition, successfully monitored the changes in shrimp freshness at temperatures of 4 °C and 28 °C, effectively prolonging the shelf life of the shrimp. Therefore, starch/ PVA/Cu-MOF composite films have good prospects for smart and active packaging applications.

Organelle-like water-borne curcumin nanoparticles with smart fluorescence for anti-counterfeiting and food quality monitoring

Current fluorescent labels are often expensive and environmentally unfriendly and tend to lose their fluorescence when combined with dry and hydrophilic substrates because of their hydrophobic nature. Thus, the development of environmentally friendly, low-cost, and scalable fluorescent materials is still highly desirable but significantly challenging, especially for anti-counterfeiting and food quality monitoring. In this study, highly fluorescent nanoparticles were prepared by mimicking organelles and using natural and sustainable curcumin as a fluorescent component. The preparation process was easily scalable via traditional seeded emulsion polymerization methods and green without using additional organic solvents. The resulting curcumin-based fluorescent nanoparticles (CFNs) were well dispersed in water, offering smart fluorescence in water-based environments or a dried polymer coating. In particular, CFNs-based coatings could be used for effective smart anti-counterfeiting and food quality monitoring. The proposed strategies may inspire the design of novel, green, and sustainable smart fluorescent materials/coatings for applications in anti-counterfeiting, smart food tags and labels, and visual sensing systems.

Analyzing Cattle Activity Patterns with Ear Tag Accelerometer Data.

In this study, we equip two breeds of cattle located in tropical and temperate climates with smart ear tags containing triaxial accelerometers to measure their activity levels across different time periods. We produce activity profiles when measured by each of four statistical features, the mean, median, standard deviation, and median absolute deviation of the Euclidean norm of either unfiltered or high-pass-filtered accelerometer readings over five-minute windows. We then aggregate the values from the 5 min windows into hourly or daily (24 h) totals to produce activity profiles for animals kept in each of the test environments. To gain a better understanding of the variation between the peak and nadir activity levels within a 24 h period, we divide each day into multiple equal-length intervals, which can range from 2 to 96 intervals. We then calculate a statistical measure, called daily differential activity (DDA), by computing the differences in feature values for each interval pair. Our findings demonstrate that patterns within the activity profile are more clearly visualised from readings that have been subject to high-pass filtering and that the median of the acceleration vector norm is the most reliable feature for characterising activity and calculating the DDA measure. The underlying causes for these differences remain elusive and is likely attributable to environmental factors, cattle breeds, or management practices. Activity profiles produced from the standard deviation (a feature routinely applied to the quantification of activity level) showed less uniformity between animals and larger variation in values overall. Assessing activity using ear tag accelerometers holds promise for monitoring animal health and welfare. However, optimal results may only be attainable when true diurnal patterns are detected and accounted for.

Liquid Crystalline Network Microstructures for Stimuli Responsive Labels with Multi-Level Encryption.

Two-photon direct laser writing enables the fabrication of shape-changing microstructures that can be exploited in stimuli responsive micro-robotics and photonics. The use of Liquid Crystalline Networks (LCN) allows to realize 3D micrometric objects that can contract along a specific direction in response to stimuli, such as temperature or light. In this paper, the fabrication of free-standing LCN microstructures is demonstrated as graphical units of a smart tag for simple physical and optical encryption. Using an array of identical pixels, information can be hidden to the observer and revealed only upon application of a specific stimulus. The reading mechanism is based on the shape-change of each pixel under stimuli and their color that combinetogether in a two-level encryption label. Once the stimulus is removed, the pixels recover their original shape and the message remains completely hidden. Therefore, an opto-mechanical equivalent of an "invisible ink" is realized. This new concept paves the way for introducing enhanced functionalities in smart micro-systems within a single lithography step, spanning from storage devices with physical encryption to complex motion actuators.

Durable and sustainable smart tags for identity management and condition monitoring: Case study for reusable packaging and recyclable data carriers

AbstractReusable packaging has been used as a case study for development of durable and sustainable smart tags that can provide both identity management and potentially also condition monitoring capabilities. Four different smart tag technologies have been investigated, including laser engraved 2D bar codes, printed 2D bar codes with combined temperature indicator, printed NFC (Near‐Field Communication) tags and RFID (Radio Frequency Identification) tags as labels. All technologies showed excellent durability towards repeated washing and heating when protective layers were used. SWOT analysis was also carried out to weight the advantages and disadvantages of the different technologies summarizing the choice of the technology per use and end‐of‐life requirements. Sustainability of the investigated technologies is discussed from the smart tag recyclability perspective and the challenges that can be seen related to the use of electronic functionalities and/or plastic‐based protective layers.

Farm Crime and Security: Evaluating Smart Tag Technology for Preventing, Tracking and Recovering Stolen Livestock

This research study evaluates the efficacy of Ceres Tag, a livestock information platform that utilises a unique smart tag, in improving farm security by preventing, interrupting, and reducing livestock theft – a prevalent issue among farmers and landholders in countries like Australia. The Ceres Tag is equipped with an accelerometer and global navigation satellite system (GNSS) technology to collect data on animal health, welfare, movement, and traceability. It was hypothesised that the Ceres Tag could combat livestock theft by enabling interventions at three key stages: rapid prevention, tracking of stolen livestock, and recovery of stolen livestock. To assess this, a mock theft of livestock was staged, accompanied by a coordinated law enforcement response. Key findings include: (1) the Ceres Tag issued a ‘high activity alert’ to farmers, indicating significant livestock agitation, within 12 minutes of the mock theft initiation; (2) utilising the data, the New South Wales (NSW) Police were able to track and interrupt the livestock theft within 25 minutes; (3) the data enabled the NSW Police to repeatedly track and interrupt the theft on three separate occasions over a 110 kilometre distance and 90-minute period; and (4) following the thieves' arrival at their destination, the NSW Police, aided by the data, recovered the stolen livestock within 20 minutes. The Ceres Tag system increases the risk of criminal behaviour in often riskless rural settings, effectively ‘hardening’ livestock as targets through technological innovation. Furthermore, the platform provides farmers with tangible evidence of a crime, substantially expediting the crime reporting process. This timely reporting, coupled with the data provided by Ceres Tag, positions police for rapid and effective intervention, thereby enhancing their capacity to investigate and resolve incidents of livestock theft. Overall, the results suggest that the Ceres Tag offers a promising technological tool for farmers and law enforcement officers alike, aimed at fortifying farm security and minimizing livestock theft.

Electrochromism and Electrofluorochromism based on Viologen Derivative with 1,10‐Phenanthroline Moiety for Multicolor Large‐Area and Patterned Display

AbstractViologens, a typical group of electrochromic materials, show rich color changes under the external electrical stimulus. Recently, some of the viologen derivatives are reported to exhibit good luminescent performance. However, their luminescence colors are difficult to adjust owing to the strong electron‐accepting properties of viologens, which seriously hinders their applications in smart light‐emitting devices. In this work, the color/emission dual‐switchable viologen derivative Phen‐vio is designed and synthesized by introducing fluorophore 1,10‐phenanthroline into 4,4′‐bipyridine, for multicolor large‐area and patterned electrochromic/electrofluorochromic devices. Under voltage driving of −2.3 and −2.8 V, the devices exhibited reversible color and fluorescence color changes from light yellow to dark orange to dark blue, and from yellow to orange to green, respectively. Moreover, the devices displayed a high color contrast ratio of up to 77% at 600 nm. More importantly, the driving voltages of the devices do not vary with the change of the device area, which is huge application potential in smart windows and tags.

Reusable Shape‐Memory Photonic Crystal Paper for Pin‐Printing and High‐Resolution Press Printing

Rewritable photonic crystal (PC) paper has the potential to significantly reduce the consumption of forest resources in the printing industry, while also being environmentally friendly and efficient. However, traditional PC papers based on solvent or photothermal responses can lead to diffusion, which can hinder printing accuracy. In this study, a novel rewritable PC paper compatible with pin‐printing is presented based on a pressure‐responsive shape‐memory PC paper. High‐resolution printing can be realized by both computer‐programmed 3D‐printed seals and pin‐printing techniques. The information written on this PC rewritable paper can be erased by water, enabling the paper to be rewritten and reused at least 8 times without any change in performance. Furthermore, the information stored on the PC paper is stable and can be stored in ordinary environments for at least 6 months without fading. The PC paper has the capability of multicolor printing with a precision finer than 100 μm and has potential in office papers, smart price tags, and anti‐counterfeiting labels.

Behavioral patterns as indicators of resilience after parturition in dairy cows

During the transition phase, dairy cows are susceptible to develop postpartum diseases. Cows that stay healthy or recover rapidly can be considered to be more resilient in comparison to those that develop postpartum diseases. An indication of loss of resilience will allow for early intervention with preventive and supportive measures before the onset of disease. We investigated which quantitative behavioral characteristics during the dry period could be used as indicators of reduced resilience after calving, using noninvasive Smart Tag neck and Smart Tag leg sensors in dairy cows (Nedap N.V.). We followed 180 cows during 2 wk before until 6 wk after parturition at 4 farms in the Netherlands. Serving as proxy for loss of resilience, as defined by the duration and severity of disease, a clinical assessment was performed twice weekly and blood samples were taken in the first and fifth week after parturition. For each cow, clinical and serum value deviations were aggregated into a total deficit score (TDS total). We also calculated TDS values relating to inflammation, locomotion, or metabolic problems, which were further divided into macro-mineral and liver-related deviations. Smart Tag neck and leg sensors provided continuous behavioral activity signals of which we calculated the average, variance, and autocorrelation during the dry period. Diurnal patterns in the behavioral activity signals were derived by fast Fourier transformation and the calculation of the nonperiodicity. To select significant predictors of resilience, we first performed a univariate analysis with TDS as dependent variable and the behavioral characteristics that were measured during the dry period, as potential predictors with cow as experimental unit. We included parity group as fixed effect and farm as random effect. Next, we performed multivariable analysis with only significant predictors, followed by a variable selection procedure to obtain a final linear mixed model with an optimal subset of predictors with parity group as fixed effect and farm as random effect. The TDS total was best predicted by average inactive time, nonperiodicity ruminating, nonperiodicity of bouts standing up and fast Fourier transformation stand still. Average inactive time was negatively correlated with average eating time, and these 2 predictors could be exchanged with only little difference in model performance. Our best performing model predicted TDS total at a cutoff level of 60 points, with a sensitivity of 79.5% and a specificity of 73.2% with a positive predicted value of 0.69 and a negative predicted value of 0.83. The models to predict the other TDS categories showed a lower predictive performance as compared with the TDS total model, which could be related to the limited sample size and therefore, low occurrence of problems within a specific TDS category. Furthermore, more resilient dairy cows are characterized by high averages of eating time with high regularity in rumination and low averages of inactive time. They reveal high regularity in standing time and transitions from lying to standing, in the dry period. These behaviors can be used as indicators of resilience and allow for preventive intervention during the dry period in vulnerable dairy cattle. However, further examination is still required to find clues for adequate intervention strategies.

A pH-indicating smart tag based on porous hydrogel as food freshness sensors

Hypothesis: The pH-indicating smart packaging and tags are identified within the general research and pH colorimetric smart tags are effective, non-invasive methods for indicating food freshness on a real-time basis, but their sensitivity is limited.Experiments: In Herin, we developed a porous hydrogel with high sensitivity, water content, modulus, and safety. Hydrogels were prepared with gellan gum, starch, and anthocyanin. The phase separations provide an adjustable porous structure, which can enhance the capture and transformation of gas from food spoilage, hence improving the sensitivity. Hydrogel is physically crosslinked by the entanglement of chains through freeze-thawing cycles, and porosity can be adjusted by the addition of starch, so avoiding the use of toxicity crosslinkers and porogen.Findings: Our study demonstrates that the gel undergoes an obvious color shift during the spoilage of milk and shrimp, revealing its potential application as a smart tag signaling food freshness.

Sugarcane-derived Bio‐Amine‐Responsive Colorimetric Films for real-time visual monitoring of the seafood freshness

A new type of bio-amine-response colorimetric film with excellent flexibility and biodegradability was fabricated by the main components of sugarcane, including sugarcane skin anthocyanin (SSA), bagasse cellulose fibers (CF), and cellulose nanofibers (CNF). Benefiting from the rich hydroxyl groups and large specific surface area of CNF, the sample of adding 10 wt% CNF in CF (CF/CNF10/SSA) presented good mechanical properties (33 Mpa), reusability (10 cycles), excellent color change (ΔE＞5), and excellent antioxidant properties (the free radical scavenging rate of ABTS: 86%). Furthermore, the film had good water resistance (water contact angle only decreases about 20° after 60 s), color stability up to 28 days, and rapid response to ammonia (1–2 s). Thus, CF/CNF10/SSA was successfully used as a low-cost, inoxidizable, and pH/NH3 responsive smart tag to monitor the freshness of seafood in real-time, achieving the high-value utilization of sugarcane waste components.

Smart tag packaging technologies: A qualitative investigation of consumers' needs and expectations

AbstractIn this paper, we attempt to better understand concerns, needs and expectations of European consumers towards the use of intelligent packaging technologies as this topic appears to need further investigation from a marketing point of view. Thus, this study contributes to the currently limited body of research on the application of smart tag technologies on food packaging by exploring information benefits to consumers and by providing insights for marketers on how these technologies could be further employed to create value for consumers, manufacturers and regulatory bodies.A qualitative user‐centred approach was employed to get insights about consumers' shared views on future packaging solutions that could be introduced by European stakeholders of the food industry using different smart labels. Focus group discussions (FGDs) were conducted online in five European countries: United Kingdom, Finland, Spain, Poland and Iceland.Respondents indicated that food safety and quality were the most important issues connected to the food value chain. Participants also identified and expressed their preferences for information that stakeholders of the food industry should deliver with smart tag labels. Smart tag labels should inform consumers about ingredients, food storage, food preparation, shelf life, health, real‐time freshness, recycling and personalised deals. In terms of preferences for different smart labels, participants indicated quick response (QR) codes and freshness indicators to be the technologies of the future for stakeholders of the food industry.

Electrostatic Induction Nanogenerator Boosted by One‐Dimensional Metastructure: Application to Energy and Information Transmitting Smart Tag System (Adv. Sci. 11/2023)

Energy and Information-Transmitting Smart Tag System An energy and information-transmitting smart tag system is designed and demonstrated based on the electrostatic induction nanogenerator. The acoustic one-dimensional metastructure showing resonant behavior boosts the performance of nanogenerators, which is enough to transfer the electrical energy and signal simultaneously in free space. More details can be found in article number 2205141 by Geon-Ju Choi, Sang-Hyun Sohn, and Il-Kyu Park.

Grocery omnichannel perishable inventories: performance measures and influencing factors

PurposePerishable inventory management for the grocery sector has become more challenging with extended omnichannel activities and emerging consumer expectations. This paper aims to identify and formalize key performance measures of omnichannel perishable inventory management (OCPI) and explore the influence of operational and market-related factors on these measures.Design/methodology/approachThe inductive approach of this research synthesizes three performance measures (product waste, lost sales and freshness) and four influencing factors (channel effect, demand variability, product perishability and shelf life visibility) for OCPI, through industry investigation, expert interviews and a systematic literature review. Treating OCPI as a complex adaptive system and considering its transaction costs, this paper formalizes the OCPI performance measures and their influencing factors in two statements and four propositions, which are then tested through numerical analysis with simulation.FindingsProduct waste, lost sales and freshness are identified as distinctive OCPI performance measures, which are influenced by product perishability, shelf life visibility, demand variability and channel effects. The OCPI sensitivity to those influencing factors is diverse, whereas those factors are found to moderate each other's effects.Practical implicationsTo manage perishables more effectively, with less waste and lost sales for the business and fresher products for the consumer, omnichannel firms need to consider store and online channel requirements and strive to reduce demand variability, extend product shelf life and facilitate item-level shelf life visibility. While flexible logistics capacity and dynamic pricing can mitigate demand variability, the product shelf life extension needs modifications in product design, production, or storage conditions. OCPI executives can also increase the product shelf life visibility through advanced stock monitoring/tracking technologies (e.g. smart tags or more comprehensive barcodes), particularly for the online channel which demands fresher products.Originality/valueThis paper provides a novel theoretical view on perishables in omnichannel systems. It specifies the OCPI performance, beyond typical inventory policies for cost minimization, while discussing its sensitivity to operations and market factors.

Electrostatic Induction Nanogenerator Boosted by One-Dimensional Metastructure: Application to Energy and Information Transmitting Smart Tag System.

The recent application of the internet of things demands the ubiquitous utilization of data and electrical power. Even with the development of a wide variety of energy-harvesting technologies, few studies have reported a device transporting electrical energy and data simultaneously. This paper reports an electrostatic induction nanogenerator (ESING) consisting of a one-dimensional metastructure that can modulate the output voltage based on the resonance of ultrasound waves to transmit energy and data simultaneously. The ESING device is fabricated using electronegative poly(vinylidene fluoride) (PVDF) membrane using a phase inversion process. The output voltage from the ESING device exhibits periodic resonant peaks as the gap between the PVDF membrane and the Al electrode changes, showing an up to 35-fold difference between the maximum and minimum output voltages depending on the resonance state. The energy and electrical signal can be transmitted simultaneously in free space because the ESING converts energy from high-frequency ultrasound waves. This paper provides proof of concept for a data and energy-transferable smart tag device based on ESING devices exhibiting resonant and non-resonant states. A device consisting of four ESINGs for a 4-bit signal is implemented to demonstrate 16 signals.

Enhancing Smart Sensor Tag Sensing Performance-Based on Modified Plasma-Assisted Electrochemical Exfoliated Graphite Nanosheet

Water that penetrates through cracks in concrete can corrode steel bars. There is a need for reliable and practical seepage sensing technology to prevent failure and determine the necessary maintenance for a concrete structure. Therefore, we propose a modified plasma-assisted electrochemical exfoliated graphite (MPGE) nanosheet smart tag. We conducted a comparative study of standard and modified RFID smart tags with sensor technology for seepage detection in concrete. The performance of both smart tags was tested and verified for seepage sensing in concrete, characterized by sensor code and frequency values. Seepage was simulated by cracking the concrete samples, immersing them for a designated time, and repeating the immersing phase with increasing durations. The test showed that the modified smart tag with 3% MPGE and an additional crosslinking agent provided the best sensitivity compared with the other nanosheet compositions. The presence of 3D segregated structures on the smart tag's sensing area successfully enhanced the sensitivity performance of seepage detection in concrete structures and is expected to benefit structural health monitoring as a novel non-destructive test method.