Experiment design - fizzyf0xy/Raman GitHub Wiki
For measuring glucose concentration in blood by Raman Spectroscopy, we need to ensure that our instruments are into proper condition and they can measure the results correctly.
The experiment design are divided as two sections below
- Glucose concentration in water (distilled water)
- Glucose concentration in blood
Before we do both experiments aboved, we need to measure all of the noises of instrument as a reference to remove background noises in preprocessing process.
The various glucose concentrations in blood are depend on fluctuant in human health conditions and their behaviours. When they eat carbohydrates, their bodies break them down into glucose, which then enters the bloodstream, causing blood sugar levels to rise. This is the comprehensive table of glucose concentration in blood from the National Institute for Clinical Excellence (NICE) Blood Sugar Level Ranges
| Target Levels by Type | Upon waking | Before meals (pre prandial) | At least 90 minutes after meals (post prandial) |
|---|---|---|---|
| Non-diabetic* | - | 4.0 to 5.9 mmol/L | under 7.8 mmol/L |
| Type 2 diabetes | - | 4 to 7 mmol/L | under 8.5 mmol/L |
| Type 1 diabetes | 5 to 7 mmol/L | 4 to 7 mmol/L | 5 to 9 mmol/L |
| Children with type 1 diabetes | 4 to 7 mmol/L | 4 to 7 mmol/L | 5 to 9 mmol/L |
*The non-diabetic figures are provided for information but are not part of NICE guidelines.
1. Glucose concentration in water
This experiment design is based on the paper name Rapid, Sensitive and Selective Optical Glucose Sensing with Stimulated Raman Scattering (SRS)
Glucose concentration preparation
The concentrations were selected to cover a wide range of human blood glucose levels to simulate both normal and unstable conditions. Hypoglycemia was defined as a blood glucose level lower than 3.9 $mol/m^3$ (70 mg/dl), whereas hyperglycemia was identified as above 10 $mol/m^3$ (180 mg/dl)
Reference concentration: 75, 50, 25, 10, 5, 2.5 $mol/m^3$
Converted reference concentration: 13.5 ,9 ,4.5 , 1.8, 0.9 ,0.45 mg/ml
1.1) Prepare glucose concentration
| Glucose concentration (mg/ml) | Preparation |
|---|---|
| 13.5 | We prepare the maximum concentration first |
| weigh glucose 0.135 g. in 13.5 ml of distilled water | |
| 9 | Take 6 ml from the first stock, and dilute with diluent to a final volume of exactly 9 ml. |
| 4.5 | Take 5 ml from the first stock, and dilute with diluent to a final volume of exactly 10 ml. |
| 1.8 | Take 4 ml from the first stock, and dilute with diluent to a final volume of exactly 10 ml. |
| 0.9 | Take 5 ml from the first stock, and dilute with diluent to a final volume of exactly 10 ml. |
| 0.45 | Take 5 ml from the first stock, and dilute with diluent to a final volume of exactly 10 ml. |
We measure each concentration by our instrument but it's not same as actual condition of the reference paper, (They recorded a linear calibration curve for glucose concentrations below 100 mol/m^3 with a theoretical limit of detection (LOD) of 3.5 $mol/m^3$ in a 0.6 s integration time.)
1.2) Prepare instrument condition
After we prepared all of glucose concentration, we'll set the first parameters of our instrument
| Parameters | Value |
|---|---|
| Laser | 785 nm |
| Grating | 600 nm |
| Accumulation time | TBA |
| Exposure time | TBA |
1.3) Measure all of glucose concentration
Then we collect three measurements on every sample for improving accuracy
2. Glucose concentration in blood
-- TBA --