How to self-test fetal bovine serum hemoglobin index? Is there a quick detection method?

The test strip approach is the most convenient: purchase urine dry chemistry test strips with a hemoglobin/occult blood module, dilute the serum 20-50 fold before spotting, and read according to the instructions. This can quickly distinguish high, medium, and low levels, but fetal bovine serum has high protein concentration and may cause false positives, so a known low-hemoglobin batch should first be used as a negative reference. If the test strip shows a strong positive, send it to a third party for specific value confirmation. Our company uses this method for initial screening, and abnormal batches are sent out for testing, keeping costs controllable. Note that after opening, test strips must be sealed and stored dry to avoid moisture.

The most practical method in the laboratory is the hemoglobin peroxidase activity colorimetric assay. Dilute a small amount of serum with PBS, add TMB chromogenic solution, measure absorbance using a microplate reader or spectrophotometer, and then use bovine hemoglobin standard to generate a standard curve. If no kit is available, you can also purchase human/bovine hemoglobin standards, prepare 4-6 concentration points, and measure the test samples and blank each time. Note that serum itself is deeply colored, so dilution and background subtraction are required. Alternatively, use a urine occult blood test strip dipped in diluted serum for semi-quantitative reading, but accuracy is limited and it is suitable for rapid screening.

Small companies can use a spectrophotometer to measure the Soret band, and a small sample volume is sufficient. Dilute 100-200 μL of serum 10-20 fold with PBS, measure the absorbance at 415 nm, and also measure at 540 nm and 576 nm to assist in assessing the oxygenation state. If the absorbance at 415 nm is significantly higher than that of the old batch, it indicates elevated hemoglobin. It is best to establish a standard curve using bovine hemoglobin standard, rather than reading a single point. If no standard is available, parallel comparison between old and new batches can be performed first, and internal control limits can be set. This method is low-cost, but requires the spectrophotometer to have accurate wavelength, and it is best to calibrate regularly.