Standards for Water Used in Molecular Biology Experiments

In molecular biology research, seemingly ordinary "water" is actually a core element throughout the entire experimental process. Its purity directly determines the accuracy and reliability of experimental results, serving as an invisible cornerstone of experimental success.

The core requirement for water in molecular biology experiments is the removal of interfering impurities. Ordinary tap water or partially purified water contains contaminants such as ions, organic matter, microorganisms, nucleases, and endotoxins, which can affect experiments through various mechanisms: metal ions inhibit Taq DNA polymerase activity, reducing PCR amplification efficiency; residual organic matter interferes with the detection of quantitative real-time PCR signals, leading to false positives or false negatives; and nucleases directly degrade DNA or RNA samples, rendering gene cloning and sequencing efforts futile. Therefore, selecting water of the appropriate purity based on the type of experiment is fundamental to molecular biology research.

Ultrapure water (Grade I water) utilizes advanced purification technology to efficiently remove nucleases, microorganisms, and endotoxins, making it a standard component for high-precision experiments. In PCR and RT-PCR experiments, nuclease-free ultrapure water prevents primer and template degradation. Gene sequencing demands extremely high water purity, and ultrapure water minimizes interference from impurities on sequencing enzyme activity and signal reading. In cell culture, bacteria- and endotoxin-free ultrapure water is crucial for preparing culture media, providing a clean and safe growth environment for cells.

The UPL series is a laboratory ultrapure water system suitable for molecular biology experiments. It removes endotoxins (<0.001 EU/mL), RNases (<1 pg/mL), DNases (<5 pg/mL), heavy metal ions (≤0.1 ppb), and microorganisms (≤1 CFU/ml).

Furthermore, ultrapure water requires scientific storage and use. It should be prepared and used immediately or stored in dedicated containers. Purity testing is necessary before experiments to avoid hidden substandard levels that could lead to experimental failure.