Oriented suspension mechanics with applications to flow linear dichrosim spectroscopy and pathogen detection

• DOI: 10.48550/arxiv.1904.01011
• Publication Date: 2019-01-01
• Authors: G. Cupples; David J. Smith; Matthew R. Hicks; Rosemary Dyson
• Keywords: Linear dichroism; Suspension; SIGNAL (programming language)

Flow linear dichroism is a biophysical spectroscopic technique that exploits the shear-induced alignment of elongated particles in suspension. Motivated by broad aim optimising sensitivity this technique, and more specifically handheld synthetic biotechnology prototype for waterborne-pathogen detection, model steady oscillating pressure-driven channel flow orientation dynamics suspension slender microscopic fibres developed. The couples Fokker-Planck equation Brownian suspensions with narrow equations, latter modified to incorporate mechanical anisotropy induced particles. signal estimated through integrating perpendicular components distribution function via an appropriate formula which takes bi-axial nature into account. For specific application pathogen detection binding M13 bacteriophage, it found increases depth are significant improving than width. Increasing $2~$mm pressure gradient $5 \times 10^4~$Pa/m essentially maximises alignment. Oscillating can produce nearly equal at frequencies, has potential practical value analysis small sample volumes.