138
A. S. Cerda-Kipper and S. Hosseini
forces in the flow channel between the detection zone and the loading zone allowed
the enzyme reactions’ steps to be carried out in a small-sized, single-layer cloth
device. The results showed that the prepared CCGTS could offer sensitive, rapid,
and quantitative biorecognition of glucose. The proposed method detected glucose
over the range of 0.1–100 mM with the limit of detection (LOD) of 0.0948 mM,
under optimal conditions, while the assay process was achieved in less than 5.5 min.
The CCGTSs demonstrate great potentials for biochemical and medical applications,
showing great promises for POCT and EPOCT (Li et al. 2017).
6.4 Recent Advances of Chemiluminescence Detection
in Microfluidic BioMEMS
Over the past few decades, microfluidic devices have attracted a great deal of attention
in various medical and biomedical fields including analytical chemistry, biochemistry, biodiagnosis, and POC. For miniaturized platforms, optical sensing methods
are desirable, specifically, when coupled with smart devices (Nagl 2015). Such
combinations of strategies simplifies the analysis process and facilitate multiplexing
(Henares et al. 2008). While integration of microfluidic systems with fluorescence
and colorimetry detection methods is common, CL can remarkably decrease the
need of integrated optical instrumentation since it does not require any external
light resources (Novo et al. 2013). Some of the latest examples of the microfluidics
BioMEMS used for CL detection are as reviewed here.
6.4.1 Recent Advances of Chemiluminescence Detection
in Lab-On-Chip (LOC) Devices
Novo et al. (2014) developed a novel two-channel U-shaped microfluidic for indirect competitive enzyme-linked immunosorbent assay (icELISA) system aimed at
detection and quantification of ochratoxin A (OTA) (Table 6.1). A thin film of a-Si:H
photodiode arrays was microfabricated on a glass substrate. The aluminum/titanium
tungsten (Al/TiW) bottom contacts were deposited by magnetron sputtering and
patterned by photolithography. Initially, TiW was etched by reactive ion etching
(RIE) followed by Al wet etching. The n-i-p a-Si:H photodiodes were deposited
by plasma-enhanced chemical vapor deposition (PECVD). Doped p-type and n-type
films were developed through addition of phosphine and diborane gases to pure silane,
respectively during film growth. Each of the devices were patterned and etched via
RIE. The sidewalls of the device were insulated by the use of silicon nitride (aSiN x ), deposited through PECVD. Sputtering was used to perform the deposition of
a transparent top contact made of ITO enabling electrical contact to the photodiode
p-layer whilst transmitting light. Lastly, a 100 nm thick passivation layer of a-SiN x
A. S. Cerda-Kipper and S. Hosseini
forces in the flow channel between the detection zone and the loading zone allowed
the enzyme reactions’ steps to be carried out in a small-sized, single-layer cloth
device. The results showed that the prepared CCGTS could offer sensitive, rapid,
and quantitative biorecognition of glucose. The proposed method detected glucose
over the range of 0.1–100 mM with the limit of detection (LOD) of 0.0948 mM,
under optimal conditions, while the assay process was achieved in less than 5.5 min.
The CCGTSs demonstrate great potentials for biochemical and medical applications,
showing great promises for POCT and EPOCT (Li et al. 2017).
6.4 Recent Advances of Chemiluminescence Detection
in Microfluidic BioMEMS
Over the past few decades, microfluidic devices have attracted a great deal of attention
in various medical and biomedical fields including analytical chemistry, biochemistry, biodiagnosis, and POC. For miniaturized platforms, optical sensing methods
are desirable, specifically, when coupled with smart devices (Nagl 2015). Such
combinations of strategies simplifies the analysis process and facilitate multiplexing
(Henares et al. 2008). While integration of microfluidic systems with fluorescence
and colorimetry detection methods is common, CL can remarkably decrease the
need of integrated optical instrumentation since it does not require any external
light resources (Novo et al. 2013). Some of the latest examples of the microfluidics
BioMEMS used for CL detection are as reviewed here.
6.4.1 Recent Advances of Chemiluminescence Detection
in Lab-On-Chip (LOC) Devices
Novo et al. (2014) developed a novel two-channel U-shaped microfluidic for indirect competitive enzyme-linked immunosorbent assay (icELISA) system aimed at
detection and quantification of ochratoxin A (OTA) (Table 6.1). A thin film of a-Si:H
photodiode arrays was microfabricated on a glass substrate. The aluminum/titanium
tungsten (Al/TiW) bottom contacts were deposited by magnetron sputtering and
patterned by photolithography. Initially, TiW was etched by reactive ion etching
(RIE) followed by Al wet etching. The n-i-p a-Si:H photodiodes were deposited
by plasma-enhanced chemical vapor deposition (PECVD). Doped p-type and n-type
films were developed through addition of phosphine and diborane gases to pure silane,
respectively during film growth. Each of the devices were patterned and etched via
RIE. The sidewalls of the device were insulated by the use of silicon nitride (aSiN x ), deposited through PECVD. Sputtering was used to perform the deposition of
a transparent top contact made of ITO enabling electrical contact to the photodiode
p-layer whilst transmitting light. Lastly, a 100 nm thick passivation layer of a-SiN x