Blood Glucose Meters: Types, Operation, and Considerations

1. Classification Based on Testing Technology

Blood glucose meters can be categorized into two main types based on their testing technology: electrochemical (electrode-type) and reflectance technology (photoelectric-type). Photoelectric blood glucose meters, similar to CD players, feature a photoelectric head. They utilize a detector to measure the intensity of reflected light from the test strip's reflective surface. This intensity, modulated by the intermediate product (a colored substance) generated from the reaction between the enzyme and glucose, is converted into glucose concentration. Their advantages include relatively low prices, but drawbacks like susceptibility to airborne contamination affecting test results, an error range of ±0.8, and a shorter lifespan (accurate for approximately two years before requiring recalibration at a service center).

Electrode-based testing, on the other hand, is more scientifically sound. It employs a current-counting device to read the number of electrons produced by the reaction between the enzyme and glucose, which is then converted into glucose concentration readings. With electrodes concealed within, these meters avoid contamination. They offer a precision of ±0.2, require no calibration under normal use, and have a longer lifespan.

2. Blood Sampling Methods

Blood glucose meters also differ in their blood sampling methods: smear-type and suction-type. Smear-type meters typically require larger blood samples, causing more pain for patients. Excessive or insufficient blood volumes can impact test results or lead to failed operations, respectively, often wasting test strips. These meters are predominantly photoelectric. In contrast, suction-type meters control blood sample measurements via the test strip, ensuring accurate results regardless of blood volume and facilitating easy operation by simply applying a blood droplet to the strip.

3. Innovative Pain-Free Blood Glucose Monitors

Patients using the new pain-free blood glucose monitors need only place the detector on the epidermis of their forearm, upper arm, or base of the palm's thumb, pressing a button for the device to automatically extract blood, apply it to the test strip, and measure glucose levels. Each test consumes just 2 microliters of blood, causing minimal sensation. These detectors can store 450 date-and-time results, displaying patients' average glucose levels over one, two, and four weeks. However, they tend to be more expensive.

4. Brands and Prices

The majority of blood glucose meters available on the market are produced abroad, such as Roche, Abbott, and Johnson & Johnson, with relatively fewer domestic products. Prices range from approximately 500 to 2000 yuan, with domestic models being cheaper and imported ones often exceeding 1000 yuan. It's crucial to note that each meter is compatible only with its specific test strips and cannot be used interchangeably. A pack of 50 test strips typically costs around 200 yuan.