A Single Magnetic Particle with Nearly Unlimited Encoding Options

Abstract

Communicating objects are demanded for product security and the concepts of a circular economy or the Internet of Nano Things. Smart additives in the form of particles can be the key to equip objects with the desired materials intelligence as their miniaturized size improves applicability and security. Beyond their proposed identification by optical signals, magnetic signals deriving from magnetic particles can hypothetically be used for identification but are to date only resolved roughly. Herein, a magnetic particle‐based toolbox is reported, that provides more than 77 billion (77 × 109) different magnetic codes, adjustable in one single particle, that can be read out unambiguously, easily, and quickly. The key towards achieving the vast code variety is a hierarchical supraparticle design that is inspired by music: similarly to how the line‐up variation of a musical ensemble yields distinguishable overtones, the variation of the supraparticle composition alters their magnetic overtones. By minimizing magnetic interactions, customizable signals are spectrally decoded by the simple method of magnetic particle spectroscopy. A large number of chemically adjustable magnetic codes and the possibility of their remote, contactless detection from within materials is a breakthrough for unexploited labeling applications and pave the way towards materials intelligence.

Colorful Luminescent Magnetic Supraparticles: Expanding the Applicability, Information Capacity, and Security of Micrometer‐Scaled Identification Taggants by Dual‐Spectral Encoding

“…Although the limits of encoding are not investigated in this paper, a library of several hundreds of unique luminescent codes seems likely, taking the small error bars and the possibility to flexibly change the utilized signal carriers into account. A combination with several ten billions of magnetic codes – as reported recently [ 100 ] – could yield trillions of unique ID signals. However, while synthesizing such an enormous amount of different code‐carrying supraparticles, unseen interaction phenomena could arise that cannot be foreseen in this paper.…”

“…Aiming to provide a taggant that can even be utilized in dark solid objects and not exclusively in liquids, ID taggants with spectral magnetic encoding were recently introduced by our group. [68,100] The ID particles can be identified via magnetic particle spectroscopy (MPS) [101] from within a material, independent of the material's optical absorption properties. [68] Moreover, the spectral nature of the magnetic code signal offers the potential to be read out independently of external factors and most importantly the taggant concentration due to self-referenced signal detection.…”

A Roadmap for Transforming Research to Invent the Batteries of the Future Designed within the European Large Scale Research Initiative BATTERY 2030+

“…In near future, decommissioned batteries will not provide sufficient information about cell chemistry and electrode condition to handle their recycling in an ideal way, which is why fast analytical measures like lithium content determination in cathodes have to be implemented. [ 149 ] The required level of expertise can only be expected if advanced AI development and novel tracer technologies, for example, marker particles with magnetic codes, [ 150 ] complement more traditional recognition means such as labelling and visual observation. The amount of information associated with batteries will increase, first through more and more sophisticated BMS, then possibly at the local level with information from sensors. Processes to handle information from these innovations during the recycling phases will have to be developed and standardized.…”

Ferrofluids and bio-ferrofluids: looking back and stepping forward

“…A detailed presentation of ferrofluid-driven assembly, functionalization procedures, and structural and magnetoresponsive properties of multicore particles is beyond the aim of this paper and we refer in this respect to recently published papers and comprehensive reviews. 43,662,668–675…”

“…A detailed presentation of ferrofluid-driven assembly, functionalization procedures, and structural and magnetoresponsive properties of multicore particles is beyond the aim of this paper and we refer in this respect to recently published papers and comprehensive reviews. 43,662,[668][669][670][671][672][673][674][675] Fig. 39 The magnetorheological effect is attributed to the field-induced large agglomerates of the disperse phase, high saturation magnetization soft (usually multi-domain iron) micrometer size particles, relative to the continuous phase, usually a mineral or synthetic oil, a composition specific to conventional magnetorheological suspensions used in a lot of high-tech devices.…”