Two-Stage Capture Employing Active Transport Enables Sensitive and Fast Biosensors

Abstract

Nanoscale sensors enable the detection of analytes with improved signal-to-noise ratio but suffer from mass transport limitations. Molecular shuttles, assembled from, e.g., antibody-functionalized microtubules and kinesin motor proteins, can selectively capture analytes from solution and deliver the analytes to a sensor patch. This two-stage process can accelerate mass transport to nanoscale biosensors and facilitate the rapid detection of analytes. Here, the possible increase of the signal-to-noise ratio is calculated, and the optimal layout of a system which integrates active transport is determined.

Superhydrophobic Alkanethiol-Coated Microsubmarines for Effective Removal of Oil

“…As common for nanomotor-based cargo pickup, the optimal motor speed will provide a trade-off between sufficient contact time and large contact rate. 31,32 Particularly attractive is the ability to tailor the polarity of the microsubmarine surface via a judicious choice of the chain length of the n-alkanethiol coating and hence their capture and transport properties. Chain length, head groups, preparation time, and other conditions (e.g., temperature) give rise to different SAM packing densities, configurations, and polarity.…”

Engineering Applications of Biomolecular Motors

“…The lessons may stimulate new approaches to classic problems in biomedical engineering, such as protein adsorption (122)(123)(124) or analyte capture (54). They also teach us to integrate biophysical insights obtained using the reductionist approach and appreciate emergent phenomena (81,125).…”

“…A rough estimate shows that the product of transport time and particle diameter has to exceed 1,000 s·nm in order for the average displacement of a cargo particle by a shuttle to exceed the average displacement of the particle by free diffusion (assuming the viscosity of water and the speed of kinesin). However, the directed nature of the transport that can take cargo without detour from location A to location B can provide a major boost to cargo delivery speed, depending on the size of the cargo loading and unloading areas (54).…”

“…Active transport of captured analyte molecules and particles can be exploited to enhance the mass transport to a sensor under specific conditions (54). In particular, advantages can be obtained for sensors of submicrometer size because diffusive transport to such a small target is particularly inefficient.…”

Determination of the persistence length of actin filaments on microcontact printed myosin patterns

“…[12]This ability to control the filaments allow the creation of a molecular motors based nanodevice which can complete a wide variety of complex task, for example biocomputation [14] or biosensing. [15][16][17][18] However, one design parameter that the majority of nanodevice have in common is that the dimensions of the structures are being reduced. This also includes any changes in direction required of the device.…”