1.4 Factors for Developing ICS
Performance of ICS depends on the following factors:
• Reaction time—rapid reaction time is better than slower reaction time.
• Flow rate—reaction rate and flow rate are inversely proportional to each other.
• Pore size—when pore size of membrane increases there appears to be a decrease
in the amount of bounded protein.
These factors should be optimized for the development of ICS with desired
performance. In addition, color intensity at the control and test line, better sensitivity towards the analyte and low consumption of immunoreagent are also very
important for the development of ICS [22].
2 Format of ICA
Various formats used in ICA are briefly described below.
2.1 Sandwich ICA
Earlier, it was mainly used for testing HIV, luteinizing hormone and human
chorionic gonadotropin (hCG) hormone. However recently, water pollutants are
also being detected by this assay. A general structure of sandwich ICS is shown in
Fig. 3. Three types of antibodies are being used in this assay: (i) Antibody 1, also
known as reaction antibody, will migrate to test and control lines. (ii) Antibody 2,
also known as detection antibody or primary antibody, is highly specific for antigen
immobilized on the test line. (iii) Antibody 3 is the specific anti-immunoglobulin
Fig. 3 Format of antibody based sandwich ICS. Reproduced from Ref. [23], copyright 2015,
Elsevier
Immunochromatographic Strip Based Sensor for the Detection …
237
Performance of ICS depends on the following factors:
• Reaction time—rapid reaction time is better than slower reaction time.
• Flow rate—reaction rate and flow rate are inversely proportional to each other.
• Pore size—when pore size of membrane increases there appears to be a decrease
in the amount of bounded protein.
These factors should be optimized for the development of ICS with desired
performance. In addition, color intensity at the control and test line, better sensitivity towards the analyte and low consumption of immunoreagent are also very
important for the development of ICS [22].
2 Format of ICA
Various formats used in ICA are briefly described below.
2.1 Sandwich ICA
Earlier, it was mainly used for testing HIV, luteinizing hormone and human
chorionic gonadotropin (hCG) hormone. However recently, water pollutants are
also being detected by this assay. A general structure of sandwich ICS is shown in
Fig. 3. Three types of antibodies are being used in this assay: (i) Antibody 1, also
known as reaction antibody, will migrate to test and control lines. (ii) Antibody 2,
also known as detection antibody or primary antibody, is highly specific for antigen
immobilized on the test line. (iii) Antibody 3 is the specific anti-immunoglobulin
Fig. 3 Format of antibody based sandwich ICS. Reproduced from Ref. [23], copyright 2015,
Elsevier
Immunochromatographic Strip Based Sensor for the Detection …
237