title: A peristaltic micro pump driven by a rotating motor with magnetically attracted steel balls.
abstract: In this paper, we present a membrane peristaltic micro pump driven by a rotating motor with magnetically attracted steel balls for lab-on-a-chip applications. The fabrication process is based on standard soft lithography technology and bonding of a PDMS layer with a PMMA substrate. A linear flow rate range ∼490 μL/min was obtained by simply varying the rotation speed of a DC motor, and a maximum back pressure of 592 Pa was achieved at a rotation speed of 43 rpm. The flow rate of the pump can also be adjusted by using steel balls with different diameters or changing the number of balls. Nevertheless, the micro pump can also work in high speed mode. A high back pressure up to 10 kPa was achieved at 500 rpm using a high speed DC motor, and an utmost flow rate up to 5 mL/min was reached.
authors.affiliation: State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instruments and Mechanology, Tsinghua University, Beijing 100084, P.R. China; E-Mails:  dum07@mails.tsinghua.edu.cn  (M.D.);  wuk05@mails.tsinghua.edu.cn  (K.W.);  zhouzy@mail.tsinghua.edu.cn  (Z.Y.Z.).
authors.forename: Min
authors.initials: M
authors.lastname: Du
authors.forename: Xiongying
authors.initials: X
authors.lastname: Ye
authors.forename: Kang
authors.initials: K
authors.lastname: Wu
authors.forename: Zhaoying
authors.initials: Z
authors.lastname: Zhou