I. Core Characteristics of the Filter Membrane (The soul of the filter cartridge adapter, distinct from the core of ordinary adapters) 

The filter membrane is the core functional component of the filter cartridge suction head. It is mostly made of polytetrafluoroethylene (PTFE) (specific for molecular detection), and all its characteristics are centered around bidirectional physical barrier, resistance to experimental environments, and non-interference with the experimental design. None of these can be lacking. 

Strong hydrophobic property 

The core basic feature is that the filter membrane does not mix with the liquid phase of water. It only allows air to pass through and can completely prevent the penetration of liquids (containing nucleic acids, enzyme solutions, impurities, etc.), while not adsorbing the sample liquid and avoiding sample loss. This is the key to achieving prevention of backflow and prevention of liquid from entering the gun barrel. 

High-efficiency bidirectional barrier property 

The core performance of the physical barrier can capture trace contaminants such as aerosols, tiny droplets, nucleic acid fragments, and enzyme molecules (particle size ≥ 0.2 μm). It not only prevents sample liquids/aerosols from entering the pipette barrel, but also prevents nucleases and dust in the barrel from falling into the sample, achieving bidirectional anti-contamination. 

Resistant to heat, corrosion and sterilization 

Suitable for the routine handling and operation environment of molecular experiments: Resistant to 121℃ high-pressure steam sterilization (the hydrophobic property and barrier property do not decrease after sterilization, and it can be sterilized repeatedly); Resistant to acids and alkalis (pH 2 - 14), and resistant to most organic solvents (anhydrous ethanol, isopropanol, DMSO, TE buffer solution, etc., all being commonly used reagents for nucleic acid extraction / amplification); Short-term resistant to temperature changes from -80℃ to 100℃, without deformation or leaching. 

No dissolution, no adsorption 

The filter membrane itself is made of inert material and does not release any chemical substances (such as plasticizers, monomers) when in contact with the sample. It also does not adsorb trace experimental substances such as nucleic acids, proteins, primers / probes, thus avoiding changes in sample concentration and the adsorption of experimental components, which could lead to result deviations. 

Seamless fit with the suction head 

The filter membrane and the inner wall of the pipette tip are bonded by a heat fusion / high-pressure bonding process, without any gaps or adhesives. This not only prevents air pressure leakage during pipetting (ensuring pipetting accuracy), but also avoids the release of adhesive causing contamination of the samples, and also prevents the filter membrane from falling off during liquid intake / discharge. 

II. Core Characteristics of the Tip Body (Balancing Precise Liquid Transfer + Basic Anti-contamination) 

The body of the pipette tip is made of polypropylene (PP) (the material used for general precision pipette consumables). It has been upgraded specifically for molecular detection purposes, with its core features focusing on precise pipetting, no contamination by impurities, and compatibility with pipette designs: 

High-purity medical-grade PP material 

Using medical-grade polypropylene without plasticizers or fluorescent agents, the material has strong inertness and does not react with experimental reagents such as nucleic acids, enzymes, and buffers. There is no substance leaching, thus avoiding chemical pollution from the very source. 

Precise dimensional tolerances 

The dimensions of the nozzle, the body of the tube, and the tip of the suction head are all precisely molded using precision molds, with extremely small tolerances: The tail of the suction head is closely fitted to the pipette tip, without any air pressure leakage, ensuring the accuracy of the volume of liquid suctioned / discharged; The tip is fine and smooth, reducing liquid hanging (especially for micro-volume pipetting, such as 1μL, 2μL), improving the thoroughness of liquid discharge, and reducing pipetting errors. 

No RNase/DNase, no pyrogens, no endotoxins 

The core technical indicators of the dedicated filter tip for molecular detection. The production process undergoes special cleaning (such as enzyme-free cleaning, ultra-pure water rinsing), is carried out in a dust-free workshop, and is verified by a third-party test. It is free of nucleases (RNase/DNase), endotoxins, and proteases, thereby avoiding degradation of nucleic acids, false positives/falsely negative results in cell culture/molecular experiments. 

Antistatic treatment 

Apply an anti-static coating / process on the surface to prevent the pipette tip from being adsorbed by dust, aerosols, and nucleic acid fragments in the air due to static electricity. At the same time, it also prevents the sample liquid from adhering to the pipette tip due to static electricity, thereby reducing the risk of contamination and improving the accuracy of pipetting.