Evaporative Deposition of Bacteria from a Sessile Drop: Effects of Suspension Aging

Abstract

In this work, we report on the evaporative deposition of bacteria from a drying aqueous drop on mica as a function of the bacterial suspension age. For sufficiently aged bacterial suspensions, residues are small and more filled-in than residues formed from fresh suspensions on similarly aged mica. In addition, the interior deposition pattern transitions from a cellular film characteristic of fresh suspensions to a cracked carpet pattern for aged suspensions. Suspension aging related changes in the residues are attributed to accumulation of organic materials such as DNA, RNA, proteins, and other bacterial components in the suspension. The aging process is also observed to be at least partially dependent on ventilation of the suspension during aging.

Pattern Formation by Staphylococcus epidermidis via Droplet Evaporation on Micropillars Arrays at a Surface

“…This phenomenon has been termed zipping-wetting and it has been observed for submillimetric-structures. 4,5 As well as forming elaborately patterned footprints on surfaces, [36][37][38][39][40] the dried pattern can have profound effect on the distribution and survival rate of bacteria on a substrate. However, little is known about how the presence of bacteria in droplets affects the drying on microstructured surfaces and how the bacterial interaction at the wetting front affects the resulting bacterial deposition over the substrate.…”

Drying of bio-colloidal sessile droplets: Advances, applications, and perspectives

“…Baughman et al [163], in 2010 experimentally studied the bacterial drying droplets deposited on the mica to understand the dependence of their aging process. The patterns formed from a fresh suspension on fresh mica are compared to that of (a) fresh mica but aged bacterial suspension and (b) fresh suspension on aged mica.…”