Holographic Glucose Sensors - Holographic Sensors - page 101

The need for minimally invasive, easy to use glucose sensors has motivated
investigation of ophthalmic glucose sensors, allowing the detection of glucose in
ocular

fluid such as tears [ 22 ]. The feasibility of non-invasive monitoring of the
concentration of glucose was investigated by incorporating a 3-APB-based holo-
graphic sensor into a contact lens [ 23 , 24 ]. Another experiment was conducted
through implanting the hologram subcutaneously just below the eye of a rabbit,
followed by xylazine-containing anaesthetic, which increased the concentration of
glucose in blood [ 25 ]. In

fl

3 min, the Bragg peak shifted by 25 nm, which was
correlated with simultaneous measurement of glucose (

*

10 mg%) in the blood.
Such a sensor can also be fabricated to semi-quantitatively measure the concen-
tration of glucose by displaying different colours or images [ 26 ]. However,

*

Table 5.1 The compositions of holographic glucose sensors and their Bragg peak shifts
Ligand (mol%) pH Concentration (mM)

[Bragg peak shift (nm)]

References

3-APB (12) 7.4 2 (20), 11 (70) [ 13 ]

3-APB (20) 7.4 2 (50), 11 (220) [ 13 ]

3-APB (25) 7.4 2 (40), 7.4 (120) [ 8 ]

3-APB (12) 7.4 2 (20), 11 (70) [ 8 ]

3-APB (20) 7.4 2 (60), 11 (220) [ 8 ]

5-F 2MAPB (15) 7.4 2 (30), 11 (120) [ 8 ]

2-APB (20) 7.1 2 (0), 12 (0) [ 17 ]

2 ( − 5), 12 ( − 23)

2-APB (20) 5.8 [ 17 ]

2-APB (20) 6.5 2 ( − 5), 12 ( − 23) [ 17 ]

2-APB (20) 7.0 2 ( − 5), 12 ( − 23) [ 17 ]

2-APB (20) 7.8 2 ( − 5), 12 ( − 23) [ 17 ]

3-APB (12) 5.8 2 ( − 3), 12 ( − 6) [ 17 ]

3-APB (12) 6.5 2 ( − 5), 12 ( − 12) [ 17 ]

3-APB (12) 7.0 2 ( − 15), 12 ( − 35) [ 17 ]

3-APB (12) 7.4 2 ( − 17), 12 ( − 45) [ 17 ]

3-APB (12) 7.8 2 ( − 10), 12 ( − 25) [ 17 ]

3-APB (12) 7.4 2 (20), 9 (70) [ 18 ]

3-APB (12) + DAPA (16) 7.4 2 ( − 30), 11 ( − 60) [ 18 ]

3-APB (12) + ATMA (12) a

7.4 4.9 ( − 60), 8.9 ( − 70) [ 20 ]

2-APB (20) + ATMA (3) 7.4 2 (8), 9 (30) [ 28 ]

2-APB (20) + PEG (3) 7.4 2 (6), 9 (20) [ 28 ]

2-APB (20) + AETA (3) 7.4 2 (4), 9 (17) [ 28 ]

2-APB (20) 7.4 2 (3), 9 (15) [ 28 ]

2-APB (20) + ATMA (9) 6.5 2 ( − 4), 11 ( − 7) [ 28 ]

2-APB (20) + ATMA (9) 7.0 2 ( − 4), 11 ( − 7) [ 28 ]

2-APB (20) + ATMA (9) 7.4 2 ( − 4), 11 ( − 7) [ 28 ]

2-APB (20) + ATMA (9) 7.8 2 ( − 4), 11 ( − 7) [ 28 ]

IS of 150 mM at 30 - 37 ° C
a

blood glucose