**4.3. Microfluidic membrane mimic**

The microfluidic membrane mimic can be defined as a part of the device with pillars or curvature or any designed structured and the tiny gap between the structures that serve as a porous membrane. The design of the microseparator can be changed to mimic the different pore sizes and shapes for the membrane study in a microfluidic device. For instance, Hassanpourfard et al. [59] designed and developed a detailed fabrication protocol for making microfluidic device that mimics the porous media to study the biofilm formation. Bacchin et al. [60] used different shapes of PDMS microseparator to ensure the uniform flow of the suspension over the width of the filtering part and to study the fouling. Derekx et al. [61] investigated the fouling behavior in a PDMS microfluidic mimic membrane by

**Figure 6.** Schematic of microfluidic device with the mimic membrane structure [30]. The dimensions are d = 50 μm, w1 = 60 μm, w<sup>2</sup> = 104 μm and P = 10 μm. The scale bar is 50 μm.

the experiment and computer simulation. The research on microfluidic membrane mimic has been mainly focused on fouling phenomena in porous media. For instance, Marty et al. [34] fabricated microfluidic devices with straight, interconnected and staggered channels to observe the biofouling nature in the microfluidic device due to biofilm. They studied the

phase separation. After making the final structured membrane the silica capillary is placed in the channel of the membrane. The membrane was then placed between two lamination sheets

The microfluidic membrane mimic can be defined as a part of the device with pillars or curvature or any designed structured and the tiny gap between the structures that serve as a porous membrane. The design of the microseparator can be changed to mimic the different pore sizes and shapes for the membrane study in a microfluidic device. For instance, Hassanpourfard et al. [59] designed and developed a detailed fabrication protocol for making microfluidic device that mimics the porous media to study the biofilm formation. Bacchin et al. [60] used different shapes of PDMS microseparator to ensure the uniform flow of the suspension over the width of the filtering part and to study the fouling. Derekx et al. [61] investigated the fouling behavior in a PDMS microfluidic mimic membrane by

**Figure 6.** Schematic of microfluidic device with the mimic membrane structure [30]. The dimensions are d = 50 μm,

w1 = 60 μm, w<sup>2</sup> = 104 μm and P = 10 μm. The scale bar is 50 μm.

to seal the chip.

302 Microfluidics and Nanofluidics

**4.3. Microfluidic membrane mimic**


**Table 2.** Summary of different types of microfluidic membrane device fabrication.

effect of different pore sizes and dead-end and pseudo cross-flow filtration modes on the biofouling during filtration. In subsequent work, they also reported that pore tortuosity and secondary flows have a significant impact on biofouling formation in the mimic system [33]. In the pseudo filtration mode, they did not work on the effect of pressure difference on the biofouling formation during filtration.

**Author details**

Edmonton, AB, Canada

2010;**47**(5):26-28

(Basel). 2012;**2**(4):804-840

on a Chip. 2012;**12**(24):5133

and Nanofluidics;**14**(5):895-902

Review of Microbiology. 2000;**54**:49-79

1997;**113**(2):215-255

, Aloke Kumar<sup>2</sup>

\*Address all correspondence to: sadrzade@ualberta.ca

and Mohtada Sadrzadeh<sup>1</sup>

1 Department of Mechanical Engineering, 10-367 Donadeo Innovation Center for Engineering, Advanced Water Research Lab (AWRL), University of Alberta,

2 Department of Mechanical Engineering, Indian Institute of Science, Bangalore, India

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\*

Microfluidic Membrane Filtration Systems to Study Biofouling

http://dx.doi.org/10.5772/intechopen.75006

305

Ishita Biswas1

**References**

Biswas et al. [30] designed a microfluidic membrane mimic by using photolithography technique to investigate the biofouling under different flow condition. The minimum pore size considered was 10 μm and the micropillars were distributed in a staggered pattern. **Figure 6** shows the schematic of their microfluidic device with the mimic membrane structure [30]. Transparent PDMS microsystem is used to mimic the membrane to study the bacteria transfer in the porous interface. The diameter and depth (in z-direction) of the micropillars are 50 μm. Their primary focus was to study the deformation mechanism of bacterial streamer that occur at the downstream location of the membrane during filtration process. They did not focus on the effect of pressure on the biofouling formation. **Table 2** shows a summary of different microfluidic membrane fabrication techniques with pore information and their application.
