How to choose a biochemical analyzer?
A biochemical analyzer, also called a clinical chemistry analyzer, is used to measure metabolites in biological samples such as blood or urine. Research on these fluids can diagnose many diseases. An example of the use of this analyzer is the measurement of urine creatinine to assess the filtration capacity of the kidneys.
When choosing a biochemical analyzer, it is important to consider whether analysis automation is required, the specificity of the reagents and the accuracy level of the measurement. It is also important to consider the detection volume (the maximum number of samples analyzed at the same time).
1. Classification of biochemical analyzers
According to the degree of automation, biochemical analyzers can be divided into 2 categories
Semi-automatic biochemical analyzer: Some operations in the analysis process (such as sample addition, heat preservation, inhalation colorimetry, result recording, etc.) need to be completed manually, while other operations can be completed automatically by the instrument.
Fully automatic biochemical analyzer: The entire process from adding samples to the results is completely automatically completed by the instrument. The operator only needs to put the sample on the reagent placement position of the analyzer, select the program to start the instrument and wait for the test report to be obtained, fully automated The biochemical analyzer has a high degree of automation and has calibration and automatic correction functions, so the errors are relatively small, the results are more accurate, and the use is more convenient.
According to the structure of the reaction device, automatic analyzers can be divided into the following categories:
(1) Flow type: (pipe type) The first generation of automatic biochemical analyzer mainly adopts the flow type. The flow type refers to the process in which the chemical reaction of each sample to be tested and reagents with the same measurement item is mixed in the same pipeline. Finish.
(2) Discrete type: refers to the chemical reaction of each sample to be tested and reagents mixed in their respective reaction cups
At present, most of the automatic biochemical analyzers used in clinical laboratories are discrete, which have the advantages of simple structure and fast detection speed.
(3) Centrifugal: It means that each sample to be tested is mixed with reagents in its own reaction tank under the action of centrifugal force to complete the chemical reaction and measure.
shortcoming:
The same centrifuge disk can generally only analyze one item at the same time; the reaction disk has no automatic cleaning function; the analysis speed is slow.
(4) The solid-phase reagent self-calibration biochemical analyzer (also known as the dry chemical automatic analyzer) is to put the reagent in the solid phase on a carrier such as film or filter paper, and each sample to be tested is dripped on the corresponding test strip for reaction and Determination. Dry chemical analyzer has the advantages of fast operation and easy to carry
(5) Bag type: refers to the use of reagent bags instead of reaction cups and cuvettes, and each sample to be tested is reacted and measured in its own reagent bag.
2. What factors need to be considered when choosing a biochemical analyzer?
(1). Accuracy
The problem that everyone pays most attention to when choosing a biochemical analyzer is undoubtedly the problem of accuracy. The result is not accurate, and the whole lot of bells and whistles are useless.
The level of accuracy is closely related to the core technology behind the instrument. There are "dry" and "wet" biochemical methods. As we have mentioned before, the dry method uses the liquid in the test sample as the reaction medium, and the test object is directly A detection method that reacts with the dry powder reagent solidified on the carrier.
Wet biochemistry means that all reactions are carried out in liquid, and "dry" is relative to "wet".
So what is the difference between dry and wet?
Dry biochemical | Wet biochemical | |
Accuracy | √ | √ |
Price | Relatively more expensive | cheaper |
Test items | 14-16 items | generally more than 30 items |
Test time | Fast | slower |
(2). The sample size should be as small as possible
Whether it is medical diagnosis or pet diagnosis, there is the problem of difficulty in blood collection. Medical diagnosis may encounter the problem of difficulty in blood collection for infants and young children and patients with anemia.
In terms of pet diagnosis, it is difficult for some exotic pets to collect blood. The shoveling officer will feel distressed when he sees that his owner collects too much blood.
Therefore, it is undoubtedly an advantage that the sample size required by the biochemical analyzer is as small as possible.
(3). The operation should be as simple as possible:
The operation steps should be controlled within 3 steps as much as possible, and the operation can be started without professional training as much as possible to reduce the cost of manual training.
(4). Less maintenance
Generally, the quality control and maintenance of large-scale instruments are more complicated. When the accuracy of the instrument detection can be guaranteed, the maintenance cost should be minimized. Instruments with less maintenance or maintenance-free are the first choice.
