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Spontaneous electrical charging of droplets by conventional pipetting.

ABSTRACT: We report that a droplet dispensed from a micropipette almost always has a considerable electrical charge of a magnitude dependent on the constituents of the droplet, on atmospheric humidity and on the coating material of pipette tip. We show that this natural electrification of a droplet originates from the charge separation between a droplet and pipette tip surface by contact with water due to the ionization of surface chemical groups. Charge on a droplet can make it difficult to detach the droplet from the pipette tip, can decrease its surface tension, can affect the chemical characteristics of solutions due to interactions with charged molecules, and can influence the combination and localization of charged bio-molecules; in all cases, the charge may affect results of experiments in which any of these factors is important. Thus, these findings reveal experimental parameters that should be controlled in experiments that use micropipettes.

SUBMITTER: Choi D

PROVIDER: S-EPMC3687225 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Spontaneous electrical charging of droplets by conventional pipetting.

Choi Dongwhi D Lee Horim H Im Do Jin DJ Kang In Seok IS Lim Geunbae G Kim Dong Sung DS Kang Kwan Hyoung KH

Scientific reports 20130101

We report that a droplet dispensed from a micropipette almost always has a considerable electrical charge of a magnitude dependent on the constituents of the droplet, on atmospheric humidity and on the coating material of pipette tip. We show that this natural electrification of a droplet originates from the charge separation between a droplet and pipette tip surface by contact with water due to the ionization of surface chemical groups. Charge on a droplet can make it difficult to detach the dr ...[more]

PMID: 23784001

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