DOI: 10.5061/dryad.cjsxksng8
title: Attachment force (mN) of bed bugs Cimex lectularius males on Perspex (PMMA) in relation to surface roughness and wettability

description: Insects attach to various surfaces that differ, among others, in roughness
 and wettability. Identifying surface characteristics that allow or prevent
 insects from attaching is an important research avenue of pest control.
 Here we take an experimental approach to analyse the attachment of common
 bed bugs, Cimex lectularius Linnaeus (1758), to Perspex (PMMA) substrates.
 We construct a reliable centrifuge device that allows the measurement of
 attachment forces at substrate roughnesses, Ra, between 0.02 and 1.3 µm
 and at two wettabilities. Our results suggest that bed bug attachment to
 surfaces is minimal at a substrate roughness of 0.2 and 0.4 µm on normal
 PMMA, where the lowest attachment force was 0.8 mN and the safety factor
 15. At lower and higher roughness, attachment forces were higher and the
 safety factor increased to a maximum of 133. On PMMA that was made
 superhydrophobic by spray-coating, the attachment was lowest (0.2 mN) at
 the lowest roughness and continuously increased with increasing roughness,
 reaching 2.5 mN and a safety factor of 46. For every roughness, attachment
 forces were lower on superhydrophobic than on normal PMMA. This knowledge
 may inspire the development of repelling substrates for bed bug control.
description: We designed a custom-made device incorporating a laser,
 phototransistor, and reed switch centrifugal method for measuring the
 attachment force. A bed bug was placed onto the disc,
 more than 10 mm from the centre of the circle. Each of the ten males
 examined was tested on all PMMA surfaces at 22-23 °C and 45 % relative
 humidity. Each bed bug was tested five times consecutively on each surface
 but there were at least 24 hours between each surface testing. We used the
 maximum force of five attachment trials, rather than the mean. In total,
 500 individual tests were carried out and statistically evaluated using
 the SigmaPlot 12.0 software (Systat Software, Inc.).
 The disc constantly accelerated until the bed bug was no longer
 able to adhere. The maximum speed achieved was approximately 1600 rpm. The
 radius, <em>r</em>, of the position of the insect was recorded
 at the point of release. The radius, together with the rotational speed
 (number of rotations per unit time), and the mass, <em>m</em>,
 of the bed bug allowed the calculation of the force that is required for
 it to be displaced from the disk (attachment force
 <em>F</em>). <em>F</em> was determined from the
 angular velocity, <em>ω</em><em> </em>(the rate of
 change of angular displacement per unit of time), at which the bug was
 detached from the disc, its mass, <em>m,</em> and the radius
 (<em>F=m r </em><em>ω
 </em><sup>2</sup>).
description: # Attachment force (mN) of bed bugs *Cimex lectularius* males on Perspex
 (PMMA) in relation to surface roughness and wettability
 [https://doi.org/10.5061/dryad.cjsxksng8](https://doi.org/10.5061/dryad.cjsxksng8) ## Description of the data and file structure Roughness: The strength of the abrasive paper used to create the roughness of the Perspex disc Wettability: The Perspex disc was either used after abrasive treatment as is ("normal") or treated with superhydrophobic spray paint (sh-phob) Attachment force: Attachment force (mN) at which the bed bugs were dislocated from the rotating disc