MEDICAL DEVICES 600 0
Reference blood glucose (mmol/L) 10
20 30 Risk level -30 Extreme
High 400 -20 Moderate 200 -10 Slight
0 0 200
applicator. While the systems have algorithms inbuilt to predict trends, generally there is a 15-minute delay in the actual blood level of glucose, which is shown on the device. Also, the sensors are still invasive, albeit minimally. There remains, therefore, a need for a truly non-invasive approach to the measurement of blood glucose. A number of approaches are currently in
development, all using novel and innovative approaches. One technique of photoacoustic spectroscopy uses a mid-infrared laser beam, which produces a thermal expansion-generating acoustic wave that is aff ected by the samples coeffi cient, as well as the physical properties of the propagation medium. In one study of 30 volunteers, it showed that
a MARD of 11.78 + 11.97% could be achieved; however, this study was undertaken with limited sampling times and while showing promise, the methodology is not proved. The correlations shown between tissue glucose measurements are impacted by skin microscopic structures as well as secretions. There has also been reports on a
photoplethysmography device. This device has been used to diagnose respiratory and cardiovascular disease. For the estimation of vital parameters like respiratory and heart rate, diff erent properties of a pulsatile wave need to be analysed. This system requires the utilisation of different sensor techniques like motion
400 Reference blood glucose (mg/dL)
sensors, skin temperature monitoring and diff erent wavelengths of light sources. One study has adapted the technique to measure blood glucose. The study used 200 volunteers who were measured pre- and post-food. These produced a glucose MARD of 5.6–20.8%. This system appears to be in the process of commercialisation.
The way forward The use of microwave technology has been reported by a number of research teams. One study, published in 2015, demonstrated
a characterisation of a microresonator split-ring system that is able to determine blood glucose levels both in vitro and in vivo, indicating that the technology may be able to measure blood glucose using a non-invasive method. Additionally, another study in 2017 independently characterised a microresonator based on an enhanced metal insulator semiconductor capacitor, which facilitated glucose recognition in vitro. This study further indicated that using a microresonator, albeit in an in vitro environment, may be the way forward to monitor and measure glucose levels in vivo. A prototype of this technology has been
developed and initially tested by Dr Chaudhry on 30 blood samples, from ten human subjects, in a study at Royal Liverpool Hospital in 2013. This study demonstrated that, in a controlled environment, the glucose concentration in whole
Outsourcing in Clinical Trials Handbook | 75 600
0
None
Measured blood glucose (mmol/L)
Measured blood glucose (mg/dL)
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120