ELISA sample collection and pre-preparation.

. ELISA sample collection and pre-preparation samples commonly used for clinical testing using ELISA generally include blood (refers to blood, intravenous blood), urine, feces, cerebrospinal fluid, thoracic abdominal fluid, prostate fluid, semen, vaginal secretions, etc., these samples are collected at a certain time, method and preservation have certain requirements.(i) Collection of clinical samples A, blood samples
some physiological factors, such as smoking, eating, exercise, mood swings, pregnancy, position, etc. can affect changes in certain components of the blood, some even day and night changes. Therefore, the collection of blood samples should try to avoid physiological factors interference, in the case of consistent conditions, if not avoidable, should be noted on the specimen of this factor.
1. Outer blood
generally choose the left ring finger inside blood, the site should be free of frostbite, inflammation, edema, damage. If the part does not meet the requirements, replace it with another finger part. For burn patients, blood can be selected at the complete skin. Because some of the blood routine tests (e.g. white blood cell count, classification, etc.) are affected by physiological factors fluctuate too much, it is appropriate to make the conditions as consistent as possible. When it comes to testing for out-of-body and clotting functions (e.g. plate plate count, bleeding time or clotting time, etc.), it is important to note whether the patient has used anticoagulant and coagulation drugs in order to reduce or avoid interference factors.
2. Intravenous blood
in addition to involving a variety of hemostotting and thrombosis testing and other items need to use anticoagulant venous plasma, the vast majority of the current testing project analysis and testing can directly use venous blood
serum
. In serum testing projects, some (e.g. blood sugar, blood lipids, etc.) are more affected by diet and circadian factors, generally to the early morning fasting blood samples, some in the blood decay faster (serum enzyme activity determination such as ACP activity, etc.), 0 to 4 degrees C storage survival is also reduced, the detection of these items must be timely and rapid, some (such as creatrolase, etc.) affected by sports and other factors. It is also important to avoid the occurrence of hemolysis when pumping blood, especially in the determination of potassium blood, LDH, etc.. B, urine samples
like blood samples, urine samples by diet, exercise, drug volume and other factors are also greater, especially the impact of diet, so in general morning urine is better than random urine. Morning urine refers to the first urine specimen after getting up in the morning, more concentrated and acidified, there are formation points (e.g. blood cells, endocrine cells, tube-shaped) relatively concentrated for easy observation. Random urine is a random urine, easy to retain, but by diet, exercise, drugs more affected, easy to appear false positive and false negative results, such as dietary proteinuria, dietary glycation, vitamin C interfere with latent blood results.
urine (patient urine collected 2 hours after lunch) is suitable for the examination of urine sugar, urine protein and urinary bilegen, at which point the urine sample increases the sensitivity of the test and detects mild lesions. The 12-hour urine cell count, or Addis count (all urine retained until 8 a.m. the next day after emptying the bladder at 8 p.m.), requires the addition of
preservatives
formaldehyde due to its long time and easy reproduction of bacteria.
The quantification of chemicals in
24-hour urine (all urine retained after emptying the bladder at 8 a.m. on the first day to 8 a.m. the next day), including protein, sugar, urine 17-ketones, 17-serotonin, catechols, Ca2 plus, etc., to detect different substances and select different preservatives for corrosion. Clean mid-section urine is mostly used for urine bacteria
culture
, requires sterile, rinsed after the vulse left samples. All urine samples should be collected in sufficient quantities, at least 12 ml, preferably 50 ml, timed urine must be collected in full, female patients should avoid vaginal secretions, blood contaminated urine samples.
C, fecal samples
stool specimens have important reference value for judging digestive diseases. Collection requires the use of clean bamboo sticks to choose containing mucus, pus and other abnormal diseases into sub-feces, the appearance of non-abnormal feces must be from the surface, depth and feces end of a number of materials. Finding parasites and counting eggs should collect 24 hours of feces. Check dysentery amoeba nourishment should be checked immediately after detocation, from the pus and soft material, insulation sent for examination.
japanese schistosomiasis eggs should take mucus, pus part, hatching hair leave at least 30g feces, and need to be treated as soon as possible. Checkeggs with a transparent film swab at 12 pm or early morning before detobation from thearound the anus and immediately mirror examination. Hidden blood test (chemical method), 3 days before the test fasting meat and animal blood-containing food and banned iron, vitamin C and so on. All fecal specimens should be examined within 1 hour of collection to prevent the formation of digestive enzymes and pH damage.. D, cerebrospinal fluid samples
cerebrospinal fluid samples are sent for examination immediately after collection, placed too long will affect the test results: such as cell degeneration, destruction, resulting in counting and classification is not correct; After cerebrospinal fluid extraction is generally divided into three sterile tubes, the first tube for bacterial culture, the second tube for chemical analysis and
immunology
examination, the third tube for general form and
smicron
examination, the order of the three tubes should not be reversed. Because the collection of specimens is difficult, all the inspection and testing process should pay attention to safety.. E, chest abdominal water samples
the same as cerebrospinal fluid specimens, after collection of specimens pay attention to safety, timely delivery for examination. Generally also divided into three tubes, one tube for routine cytological examination, one tube biochemical examination, one tube of bacterial culture, the order is the same as cerebrospinal fluid.. F, prostate fluid samples
prostate fluid samples collected by prostate massage, when the amount of liquid directly drip on the slide timely delivery inspection, attention should be paid to prevent the specimen from steaming dry, the amount of time collected in the clean
drying
test tube. If the massage does not produce prostate fluid, you can check the urine residue after the massage.. G, semen samples
semen specimens should be abstinence 3 to 7 days before collection, after draining urine can be masturbating or other methods to drain semen directly into a clean container, insulation and timely delivery. Due to the large changes in sperm production during the day, 2 to 3 examinations (1 to 2 weeks each interval) should generally be examined before diagnosis can be made.. H, vaginal secretion samples
24 hours before the collection of vaginal specimens should be prohibited room, bath, vaginal examination, vaginal irrigation and local medicine, etc. , the equipment used to obtain materials should be cleaned. Generally soaked with saline cotton swabs from the deep part of the vagina or vaginal dome, cervical tube mouth, etc. , to make physiological saline smears after observation of vaginal secretion specimens, menstrual female patients should not check vaginal secretion specimens.. (ii) ELISA's sample test preparation
must have a complete plan before collecting samples, and it must be clear whether the parts to be tested are stable enough. Samples tested on the day after collection
stored in a timely manner at 4 degrees C. For the samples retested the next day, the timely sub-packing freeze exists at -20 degrees C standby, conditional, preferably -70 degrees C frozen standby. Specimens should avoid repeated freezing and thawing.
liquid specimens: including serum, plasma, urine, chest ascension, cerebrospinal fluid,
cell culture
etc.
1. Serum: . After 10-20 minutes of natural coagulation of blood at room temperature, centrifugation for about 20 minutes (2000-3000 ropm). Carefully collect on the clear. If precipitation is formed during preservation, it should be centrifugated again.
2. Plasma: . EDTA, sodium citrate or heparin should be selected as anticoagulants according to the requirements of the specimen, after 10-20 minutes of mixing, centrifugation for about 20 minutes (2000-3000 g/min). Carefully collect on the clear. If precipitation is formed during preservation, it should be centrifugated again.
3. Urine: . Collected with sterile tubes. Centrifuge for about 20 minutes (2000-3000 ropm). Carefully collect on the clear. If precipitation is formed during preservation, it should be centrifugated again. Chest ascertes and cerebrospinal fluid are carried out by reference here.
4. Cell culture is clear: . When detecting secretive parts, collect them with sterile tubes. Centrifuge for about 20 minutes (2000-3000 ropm). Carefully collect on the clear.
. When cultured cells
detecting the contents of cells, the cell suspension is diluted with PBS (PH7.2-7.4) at a cell concentration of about 1 million/ml. By repeatedly freezing or adding tissue protein extraction
reagents
to destroy and release the cell's in-cells. Centrifuge for about 20 minutes (2000-3000 ropm). Carefully collect on the clear. If precipitation is formed during preservation, it should be centrifugated again.
6. Tissue specimens
weight after cutting the specimens. Add a certain amount of PBS, PH7.4. Quickly freeze and store the backup with liquid nitrogen. The specimen remains at a temperature of 2-8 degrees Celsius after melting. Add a certain amount of PBS (PH7.4), or tissue protein extraction reagents, and homogenize the specimen with a manual or homogenizer. Centrifuge for about 20 minutes (2000-3000 ropm). Carefully collect on the clear. After packing one to be tested, the rest of the frozen spare.
.