First, gel preparation 1. When the microwave dissolves the agarose, the glue boils and overflows. When the microwave is heated, the glue may violently boil. 1) The total liquid volume should not exceed 50% of the capacity of the triangular flask. 2) 2% or more glue set to heat in medium heat 3) When the glue is boiled vigorously, stop heating, remove the triangular cone bottle, wear heat-proof gloves, carefully shake the triangular cone bottle, then heat again, the glue boils until the glue is clear, to ensure that the agarose is completely dissolved. 2. Agarose electrophoresis image background is blurred If the agarose is not completely dissolved, the background of the electrophoresis image will be blurred. The fully dissolved agarose gel is clear and the inner wall of the flask should not adhere to the agarose particles. 3. After heating, the water will evaporate. If necessary, add hot distilled water to make up the original weight and shake well. Second, electrophoresis 1. DNA bands are blurred, trailing 1) DNA degradation. Avoid nuclease contamination. 2) There is too much DNA loading. Reduce the amount of DNA loaded in the gel. 3) The old electrophoresis buffer: After the electrophoresis buffer is used for many times, the ionic strength is lowered, the pH value is increased, and the buffering capacity is weakened, thereby affecting the electrophoresis effect. It is recommended to change the running buffer frequently. 4) The electrophoresis conditions are not suitable. The voltage should not exceed 20V/cm during electrophoresis, temperature <30 °C, large DNA strand, temperature should be <15 °C, check whether the running buffer used has sufficient buffering capacity. 5) DNA-like salt is too high. Excess salt was removed by ethanol precipitation before swimming. 6) There is protein contamination. Extract the protein before electrophoresis. 7) DNA denaturation. Do not heat before electrophoresis, dilute DNA with 20 mM NaCl buffer. 2. DNA bands are weak or no DNA bands 1) Insufficient sample loading of DNA: Increase the amount of DNA loaded. 2) DNA degradation: avoid nuclease contamination of DNA. 3) DNA out of the gel: shorten the electrophoresis time, reduce the voltage, and enhance the gel concentration. 4) DNA bands with similar molecular sizes are difficult to distinguish. Increase the electrophoresis time and use the correct gel concentration. 5) DNA denaturation: Do not heat the DNA strand at high temperature before electrophoresis, and dilute the DNA with 20 mM NaCl Buffer. 6) The DNA strand is huge and conventional gel electrophoresis is not suitable. Analysis on pulse gel electrophoresis. 3.DNA MARKER strip twist 1) The buffer for the preparation of the gel and the running buffer are not prepared at the same time. Use a buffer that is prepared at the same time. The buffer solution can be 1 - 2mm above the liquid level during electrophoresis. 2) The voltage is too high during electrophoresis. You can use a lower voltage (3V/cm) 15 minutes before electrophoresis, and then adjust the voltage after the strip is taken out. 3) Try to add the sample as slowly as possible, and then add the voltage after the sample has settled naturally. Handheld Glycohemoglobin HbA1c Test Kit A1C Test,Diabetes Management,Glycated Hemoglobin Test,Glycated Hemoglobin Assay Wuxi BioHermes Bio & Medical Technology Co., Ltd. , https://www.biohermesglobal.com