Table of Contents

How to design a blood Glucometer?

How to design a blood Glucometer? Diabetes Mellitus is a condition that causes the blood glucose level to rise. The reason for this rise is that the body is not capable to produce sufficient amounts of insulin. If not controlled, Diabetes Mellitus can lead to serious illnesses such as cardiovascular diseases, renal failure, visual loss etc. The risks associated with Diabetes can be significantly reduced by properly monitoring and controlling the blood glucose level. Unfortunately, nowadays, the commonly used blood sugar measurement methods use invasive techniques.

These techniques are painful and can cause complications related to skin. So this article demonstrates a possible idea to measure blood glucose level non-invasively. In this report we used infrared based light emitting diode as transmitter over which the finger is placed for the measurement of blood glucose. The intensity of the received light depends on the glucose concentration present in the blood.

This received signal is then fed into Arduino where it is processed and a digital blood glucose value is displayed on a Liquefied Crystal Display (LCD). This report will let the Diabetic patients to measure their blood glucose level without pain, with an accuracy that is in the acceptable range.

Diabetes is a kind of illness in which the blood glucose level in human body increases radically from its typical level. This is either because of reasons like deficient creation of insulin in platelets or because of improper reaction of body cells to the insulin or both. This can prompt real inconveniences like heart failure and individuals end up daze in serious cases.

Diabetes is a condition of body in which it cannot generate adequate amount of insulin required to keep up level of blood glucose. The quantity of diabetic individuals is expanding over the world because of population growth, unfortunate eating routine, corpulence and absence of physical action.
According to World Health Organization (WHO), the estimated number of diabetic people is more than 200 million and about 35 million people die every year due to the diabetic illness. In 2030, diabetes is projected to be the 7th lead reason of the death in the world.

In the report of International Diabetes Federation (IDF), in 2013, it is around about 382 million people that suffered from diabetes and in 2035 it is expected that this amount reached to 592 million. India is named as “Diabetes Capital” of the world because about 65 million people suffered from diabetes. The countries suffering from diabetes include China, India and USA. Recent research has shown that the health hazards related to diabetes are minimized when the blood sugar level is properly maintained by a monitoring device.

A continuous monitoring of blood sugar level is highly required for efficient management of diabetes illness. Now a days method named “Finger Piercing” is practically used for continuous measurement of blood sugar level but it is painful and sometimes discourages the patient. As the technology becomes immense and it involves the non-invasive methods, which allows us, frequent, efficient and constant measurement of blood sugar level without giving pain and bleeding to the patient finger and it will also courage the patient in future.

Today, none of the accessible and approachable method can fix diabetes totally. By keeping the blood glucose level in normal range, it is possible to manage problems associated with the diabetic patient. Standard glucose observing, diet plan, insulin shots and oral meds are the establishment of diabetes treatment. These methods are the main step in productive administration of diabetes to control blood glucose. The majority of industrially accessible glucose estimation gadgets are intrusive. Diabetic patients need to screen their blood glucose level a few times on every day. The intrusive techniques are irritating and have peril of spreading infectious diseases.

A Glucometer is an apparatus whose purpose is to measure the glucose intensity in blood. This is frequently done by taking a blood sample from the subject. Diabetes which involves lowering the blood glucose level and other risk factors that damage blood vessels can be treated with the help of glucometer. Retinopathy and kidney diseases can also be treated with the help of glucometer. People have to control the level of blood glucose in order to lessen the possibility of hyperglycemia. The essential part of managing diabetes is to check the glucose level daily.

The technologies available in the market for measurement of blood glucose level are invasive. Invasive methods are painful, time consuming, and expensive. There is also a potential risk of spreading diseases like Hepatitis & HIV when using invasive methods. This makes the process of continuous blood glucose monitoring a tedious one. Blood glucose monitoring is to measure the amount of glucose in blood, for the patients with symptoms of abnormally high or low blood glucose levels in the body. The patients with low glucose level have to take appropriate insulin doses on time. Now a day’s home-use glucometers are available, which helps in the continuous monitoring process and improves the quality of life of diabetic patients. However, such monitors require new expensive test-strips.

Non-invasive blood glucose methods are without pain, convenient and cost-effective to diabetic patients. The method which is used for continuous monitoring of glucose levels in human body for both Type I and Type II diabetic patients is called Non-invasive blood glucose measurement. Improving glucose measurement techniques to make the measurement simple and reliable, and it gained a lot of consideration from both academic and industrial researchers. Measurement of blood glucose in a painless and non-invasive manner involves passing a selected beam of wavelength of near-infrared light through the human tissue. For the accuracy of blood glucose values, the viable spectral regions are studied.

Non-obtrusive methodologies are all the more appealing and extraordinary substitutes to these contraptions. These glucose estimation strategies got a great deal of consideration for scholastic and mechanical scientists. People are more relaxed and feel comfortable when they used non-invasive approached for testing their blood glucose level. In this manner, non-invasive glucose monitoring technique should be built. The main advantage of this method is relief from finger piercing. It also reduces the cost of healthcare. A great deal of research work is done on non-obtrusive blood glucose estimation in the course of the most recent decade. Different optical techniques are used for this purpose which are described below:

Raman Spectroscopy:

It relies on the utilization of a laser light to invigorate wavering and turn in particles. Subsequent outflow of scattered light impacted by this atom vibration, depends on the gathering of the glucose particle. This is prudent as a result of the use of settled wavelength lasers that moderately costs low. This strategy experiences the changeability of the laser wavelength and quality, and long ghostly anchoring conditions.

Fluorescent spectroscopy:

This method analyzes the fluorescence from the model. It has additionally been demonstrated that fluorescence intensity relies upon the glucose absorption in the solution. Light in the observable range can be utilized and more adequate for examining the fluorescence of tissues. The expansion of fluorescent materials in tissues prompts solid dispersing.

Polarization change:

A first non-invasive technique for the measurement of blood glucose level in human body is polarization change. This make use of visible region of light. The major drawback of this method is the scattering property of tissues because light is depolarizing due to the scattering.

Mid Infrared spectroscopy:

It is based on light in the 2400–10,000nm spectrums. The physical principle of this technique is the same as of Near Infrared Region (NIR). When compared to the NIR, mid infrared emits decreasing dispersion and increasing absorption due to the higher wavelength. Mid-infrared compared to NIR produces sharper. But the penetration depth is poor.

Near infrared spectroscopy (NIR):

The light centered around the body is in part consumed and scattered, because of its excitation of atomic vibration inside the tissue. Glucose focus can be evaluated by shifting light force and transferred through a glucose holding tissues and reflected by the tissues itself. The infiltration profundity is high. But the measured signal is very weak.
Near Infrared region: The following three regions are generally accessible.

The mix district: 2.0 to 2.5 microns
The principal hint district: 1.54 to 1.82 microns
The short wavelength near infrared (SW-NIR) district: 0.7-1.33 microns

Glucose has its ingestion in both blend and first suggestion place. The whole close infrared area of the electromagnetic range incorporates light with wavelength extending from 0.7 to 2.5 microns. Close infrared spectroscopic data relates to harmonics of hints and mix section of principal vibrational changes all the more every now and again connected with mid-infrared spectroscopy. NIR’s suggestions and mix retentions depend on CH, OH and NH atomic sets.
Non-invasive techniques are superior as compared to the invasive techniques. There are many approaches to build a non-invasive glucose meter because it is highly demanded by the society. One approaches which is used to design a non-invasive glucose meter is using an infrared technique in which the patient put a finger on the sensor of the device and device shows the glucose level on the liquid crystal display. The glucose level is measured on the basis of scattering and absorption of light through the blood.
Therefore, it is necessary to develop a non-invasive technique because it would be easy and convenient for the patient. The main advantage if the non-invasive technique is that the patient will get a relief from the finger piercing which is painful to the patient and it reduces the healthcare cost.

Block Diagram of Blood Glucose Estimation Using Optical Technique

In previous work, the non-invasive type blood glucose prototype was designed. Light was exposed on the region of interest through an optical source with the human intervention. The transmitted light from the optical source was detected using an equivalent photodiode. The analog signal from photodiode was converted and amplified by the signal conditioning unit of microprocessor and the corresponding blood glucose value was identified and displayed on LCD.

Here the Non-invasive blood glucose device is developed using the optical techniques. The optical technique used in this research paper was Near-Infrared. NIR was used due to its high penetration in skin. The circuit was designed with NIR LED having wavelength of 940nm with equivalent photo detector. In this device, the near infrared light was impinged on the area under measurement. The transmittance of NIR light depends on the amount of glucose molecules in the path of light. The photodetector voltage was mapped with the database to obtain the current glucose value.

Basic Block Diagram of Glucose Monitoring System

Firstly, the most significant and basic task towards the completion of the system was to design a sensor mounted in a probe that consists of infrared LED and phototransistor. Here IR LED acts as a transmitter and phototransistor as a receiver. Secondly, to get rid of noises, the output of the phototransistor was passed through a low pass filter. Thirdly, output obtained after filtering was directed to the microcontroller. Microcontroller converts the analog output into digital form. After conversion, output was processed using calibration and mathematical model to calculate blood glucose level. Finally, value of glucose in the blood was displayed on LCD.