At present, there are many kinds of biochemical reagents, how to use correctly and reasonably, and fully improve the accuracy of the test results, so that the better for clinical diagnostic services.
1, high-quality equipment water
High quality equipment water is a very important part of the use of good test reagents. Because of the determination of the ion type of projects: such as copper, iron, zinc, calcium, Mg, phosphorus. These projects in the use of process, the quality of water apparatus is very important, although now general hospital of biochemical analyzer with water system, but water system are basically preparing deionized water, ion exchange resin in use after a period of time exchange capacity decreased significantly, scheduled for replacement is required, otherwise the business were prepared by aqueous ion content, conductivity is high. The use of excessive water washing apparatus, a direct impact on the test results. Another example is the blood ammonia and carbon dioxide project, if the water quality is not good, water apparatus itself containing ammonia and carbon dioxide is high, detection results of the project will be seriously affected. And if the serum contains GLDH, while the presence of ammonia water equipment, the consumption of NADH, so that the use of NADH continuous monitoring of the results of the high enzyme. Solution: regular monitoring of water quality, when the instrument water resistance is less than 1.0MQ to replace the ion exchange resin or activated carbon.
2, the samples of the timely separation and determination
The timely separation and determination of the samples is the most important part of the test reagent because of the change of the NADH into the NAD+ change rate to detect the substance content of the test are more or less affected by the blood storage time. The reason is that the longer the whole blood storage, red blood cells in the serum of glucose for anaerobic fermentation to produce pyruvate, pyruvate to NAD+ into NADH, so that the results of false increase. Solution: prepare and clinical communication, the researchers took blood and specimen delivery personnel (staff transfer) training; II in serum was separated and detected in a timely manner; (3) can also be full automatic biochemical analyzer on the delay time is set greater than 60 seconds, this reagent during the delay period to eliminate pyruvate interference, completely avoid the emergence of false positive results.
3, cross contamination
3.1 the cross contamination caused by the cleaning problem of the biochemical analyzer is in the use of the automatic biochemical analyzer, the cross contamination of the instrument is one of the reasons that cause the deviation of the experimental results. Due to full automatic biochemical analyzer reagents needles need to be in contact with various reagents, generally difficult to clean thoroughly, so easy to cause analysis project carry pollution. And biochemistry determination often requires only a few microliters of sample, reagent often need to several hundred microliters, especially in no automatic flushing procedure of flow cell type biochemical analyzer, due to the former with the phenomenon of the existence, if a sample for high values of the sample, is connected to the first low value samples results should be carefully report. Not only no flushing procedure of biochemical analysis instrument of this phenomenon is automatic flushing procedure of automatic biochemical analyzer and cross contamination, such as Beckman automatic biochemistry analyzer CX4 and its reagent ceiling needle (probe), sample aspiration needle and the reaction stirring rod is benefit with high-pressure washing liquid, and then use high-pressure compressed air dryer, sometimes due to fluid pressure and compressed air pressure low, the reagent suction needle, absorb the sample needle and the reaction mixing rod is not washed clean, blow dry, resulting in reaction tank between pollution, reagent for cross contamination, so that the test results to deviate from. Another noteworthy problem is many biochemical instruments due to the frequent use of the sample probe and reagent plus needle syringe wear aggravated or syringes "TEFLON" suction head not timely replacement, sucking needle like or reagent needle sealing layer increases, resulting in leakage phenomenon is caused by one of the important reasons for between sample and reagent between pollution. Reagent sampling or sample suction is not accurate, usually lead to the use of rate test of the specimen system is low or high. It is well known that rate method calculation factor is the volume of sample and reagent is involved in determining the, if the sample volume or adding reagent volume are not allowed, resulting in real rate calculation factor and theoretical calculation factor deviating from, so that the test result is not accurate. Solution: 1. Regular equipment maintenance; according to the requirements of the timely replacement of parts; (3) on a regular basis to calibrate the instrument; (4) automatic biochemical analysis of sample and reagent consumption, a small amount of residual will affect the test results, every day using anhydrous alcohol scrub and the regular replacement of dry stick to ensure color cup cleaning without leaving residue, to avoid cross contamination color cup.
Cross contamination between 3.2 inspection items in full automatic biochemical analyzer using, we find that influence followed by subsequent projects test results, caused by the impact of one of the reasons is a reagent containing another test of the determination of material directly interfere with the test results of a project. The two reason is that the test result is interfered by the substance which changes the reaction condition of the other test or the substance of the reaction process. For example: in the TP reagent contains a large number of CuSO4, if the Cu on the back of the TP project detection, will make the test results on the high side or repeatability is poor. Another example (P) in the presence of phosphate, behind the project, TBA in containing cholate project behind will make the detection result is high or poor reproducibility. GLU placed behind the CK and CK-MB projects may cause the test results to be high or poor reproducibility. LDH placed behind the ALT and AST projects may cause the test results to be high or poor reproducibility. Mg placed in the ALP and other items containing magnesium ions may cause the detection result is high or poor reproducibility. Ca on the back of the a-Amy project may cause the test results to be high or poor reproducibility. Mg reagent (CALMAGITE method) contains EGTA, will interfere with the results of the determination of Ca. In addition, we found that the pH value of the adjacent two items is too large or reaction to PH