National Nano Center made new progress in the direction of intelligent anti-tumor nano drugs

[ Instrument R&D of Instrumentation Network ] On June 22, a team of researchers Nie Guangjun and Wu Yan from the National Nanoscience Center and academician Zhao Yuliang from the Chinese Academy of Sciences published a research paper online in the journal Nature Biomedical Engineering. Through intelligent nano-drugs loaded with procoagulant factors and chemotherapeutic drugs, we can achieve specific targeted embolization of tumor blood vessels and promote the simultaneous enrichment of chemotherapeutic drugs to the tumor marginal area without blood supply or blood vessel growth, effectively improving the effectiveness of vascular embolization therapy treatment effect. The research provides new ideas for the development of new anti-tumor vascular drugs, and at the same time has a guiding significance for improving the clinical design of existing embolization therapy.

Tumor vascular embolization therapy is a treatment method that forms blood clots in the formed tumor blood vessels, blocks the tumor blood supply, and makes tumor cells starve and die due to lack of nutrition and oxygen. For the majority of clinical cancer patients, anti-tumor therapy targets mostly already vascularized tumors. Therefore, tumor vascular embolization therapy presents a broad-spectrum and highly effective clinical application prospect. However, the search for safe and effective vascular embolization therapy is still a "bottleneck" problem in this research field. Since 2011, Nie Guangjun's team has carried out a series of research work on the regulation of the vascular system in the tumor microenvironment by intelligent nano drugs.

In response to the above scientific challenges, with the support and guidance of Zhao Yuliang, Li Suping, Ding Baoquan, and Nie Guangjun jointly developed a new type of DNA nanorobot, loading thrombin into it, realizing the precise positioning and controllability of thrombin in tumor tissues Exposure, selective induction of tumor vascular embolism, the scientific purpose of effectively "starving" tumors (Nature Biotechnology, 2018, 3, 258-264).

On the other hand, the platelets in the tumor blood vessels protect the integrity of the blood vessels by secreting the particulate content and/or directly adhering to the surface of the blood vessel endothelium. This special function of platelets prevents the penetration of drugs across the endothelium in the tumor, which limits Efficacy. In response to this scientific problem, Nie Guangjun and Li Suping jointly developed a polymer nano-drug targeted to clear local platelets of tumors, targetedly clearing local platelets of tumors, and expanding the vascular endothelial space, thereby improving the intratumoral enrichment of chemotherapy drugs (Nature Biomedical Engineering , 2017, 1, 667-679).

The research team was recently invited to regulate the microvascular environment of tumor vasculature by smart nano drugs in Accounts of Chemical Research (2019, 52, 2703-2712), Medicinal Research Review (2020, 40, 1084-1102) and Trends in Biotechnology (2019, 6, 573-577) and other authors wrote reviews and review articles, systematically summarizing the latest progress and challenges of the tumor microenvironment vasculature.

The above series of research work have received support from the Nanotechnology Special Project of the Ministry of Science and Technology's Key R&D Program, the Strategic Pilot Technology Special Project of the Chinese Academy of Sciences (Category B), the National Natural Science Foundation of China's key projects and innovative groups.

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Types of ion exchange resin:

Cation Exchange Resin:

Strong Acid Cation (SAC) Resins: These resins contain sulfonic acid groups and are used to remove positively charged ions (cations) such as calcium (Ca²âº), magnesium (Mg²âº), and other heavy metals. SAC resins are commonly used in water softening applications.

Weak Acid Cation (WAC) Resins: These resins contain carboxylic acid groups and are effective at removing cations, particularly in applications where water has a high alkalinity.

Anion Exchange Resin:

Strong Base Anion (SBA) Resins: These resins contain quaternary ammonium groups and are used to remove negatively charged ions (anions) such as sulfate (SOâ‚„²â»), nitrate (NO₃⁻), and chloride (Cl⁻). SBA resins are often used in deionization processes.

Weak Base Anion (WBA) Resins: These resins contain tertiary amine groups and are effective at removing anions from solutions with lower pH levels.

Applications of Water Treatment Resins:

1.Water Softening:

Cation exchange resins are commonly used to replace calcium and magnesium ions in hard water with sodium or potassium ions, thus preventing scale buildup in pipes and appliances.

2.Deionization:

Both cation and anion exchange resins are used together in mixed bed or separate bed configurations to remove all ionic species from water, producing highly purified water. This is crucial in applications such as laboratory water, pharmaceuticals, and microelectronics manufacturing.

3.Demineralization:

This process involves using both types of resins to remove dissolved salts from water. It's used in boiler feedwater treatment and other industrial processes where mineral-free water is required.

4.Selective Ion Removal:

Specialized resins can be used to target specific contaminants, such as heavy metals, nitrates, or arsenic, from drinking water and wastewater.

5.Maintenance and Regeneration

Water treatment resins require periodic regeneration to restore their ion exchange capacity. Regeneration involves flushing the resin with a concentrated solution of the ions that the resin initially releases. For example:

SAC resins are regenerated with a salt (sodium chloride) solution.

SBA resins are regenerated with a caustic (sodium hydroxide) solution.

Regular maintenance and proper regeneration are essential to ensure the longevity and efficiency of the resins.

Conclusion

Water treatment resins are a critical component of many water purification systems, providing efficient removal of a variety of contaminants. Their effectiveness and versatility make them suitable for a wide range of applications, from residential water softening to industrial demineralization. Understanding the types and functions of these resins can help in selecting the right one for specific water treatment needs.