3. Results and discussion
3.1. The design principle of tree-shaped and Y-shaped patterns
The main aim of designing tree-shaped or Y-shaped pattern is to
integrate a self-calibration on the test strip. The pattern of the test
sheet can be flexibly designed according to the need and requirement
of the determination of the analyte. For detecting multiplex
concentration of standard glucose solutions, tree-shaped strip has
the advantages because it can assure the uniformity of microflows
in different branches and the sample information can be collected
at the same time. In our work, the main purpose of tree-shaped strip
was to obtain the calibration curves. The greatest advantage of selfcalibration
is that the affects of environmental conditions including
temperature, humidity, pressure, or etc. can be minimized to a large
extent. In this situation, no consideration of different conditions
is necessary to be included and systematic errors can be avoided,
the semiquantitative assay can also be achieved rapidly. Thus, the
paper-based sensor provides a rapid, point-of-care testing of glucose
in resource limited areas and developing countries. However,
Y-shaped strip should be chosen for detecting single component.
The color intensity in both the standard solution with the normal
concentration and the unknown concentration in blood serum can
be collected at the same time. Y-shaped strip can semiquantitatively
judge whether the concentration in blood serum is low level,
normal level or high level, and directly provide a result of “Yes or
No”.