ELISA setting negative, positive, blank control experiment results validity

What is "Validity"? To obtain an accurate "Validity" evaluation of the test result, it will be related to: Why are the three indispensable controls such as "negative, positive and blank" set up? What kind of The substance serves as a "negative, positive and blank control (product)"? How to set up the "three controls", need to set a few wells? How to "approval, trade-off and calculation" of the obtained measured value? What is the difference between the mean value (PCx) and the negative control mean value (NCx) (PN, or NP) to make a final decision on the "validity of the test results"?… And so on The ELISA reagent "Instruction Manual" has detailed and detailed instructions. There are both theoretical key points and specific and detailed explanations. It is a pity that when the ELISA detection boom started in China around 90 years, in the voice of "foreign reagent instructions are too detailed, too complicated, not easy to understand, ..." and so on, it just caters to domestic businesses. "Will". Since then, the instructions for domestic ELISA reagents have become increasingly simple. There are two "benefits" among merchants: one of the benefits is to use A4, or B5, or even a piece of paper smaller than B5, instead of several pages of "instructions" for international reagents (equivalent to a "Manual"), can save a large amount of printing costs every year; the second advantage is that, as the international reagent instructions explain to the users the detailed content indicating the quality of this reagent, the so-called "instructions" for domestic reagents can be " "Delete, avoid, reject" to inform and promise users. It is a pity that I have collected the original manuals of the relevant reagents such as <美> Abbott, <French> Pasteur, <Dutch> Aksu, etc. that I collected around 90 years ago. Recently, a friend of the Hangzhou Quarantine Bureau sent a Chinese version of "Human Immunodeficiency Virus Antigen Antibody Diagnostic Kit (Enzyme-linked Immunoassay) User's Manual" in Chinese. After comparing and reading, I deeply feel that this is a real "User's Manual"! I can find answers to several "concepts and questions" mentioned below. I now refer to the relevant content of my 1993 "Hepatitis ELISA Reagent Quality and Test Results Effectiveness Evaluation" conference presentation, and express the following understanding and discussion on "Three Controls and Test Results Effectiveness". 2. Three control requirements and use ELISA test, according to the requirements of the reagent instructions, each test, each plate must be set up the following three control and use:

1. Blank control: only use the diluent instead of the test sample to observe the "background" color of the final reaction, and use it to eliminate and deduct the "background" of the microplate reader, that is: read with the background as "zero" Absorbance values ​​of positive and negative control wells and sample detection wells (A); or, subtract the background absorbance of the blank control when calculating the negative control mean (NCx), positive control mean (PCx), and S / CO value of the sample reading value. The microplate reader in the early years did not automatically deduct the reading of the blank control well. This kind of enzyme labeling is no longer used. The meaning of this paragraph is to supplement the purpose of setting the blank control. How to read the blank hole according to the instructions. For example, the Chinese version of the "Human Immunodeficiency Virus Antigen and Antibody Diagnostic Kit (Enzyme-linked Immunoassay) User's Manual" in the Chinese version of BioMerieux China Co., Ltd. prompts: read blanks in air (without placing racks and slats) at Single wavelength), or 450nm and 620-700mn (substrate is TMB) reference wavelength for reading.

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