Chinese Journal of Magnetic Resonance ›› 2024, Vol. 41 ›› Issue (4): 382-392.doi: 10.11938/cjmr20243101

• Articles • Previous Articles     Next Articles

Design and Research of the dDNP Automated Dissolution System

ZENG Xiangzheng1,2, CHEN Junfei2, HUANG Chongyang2, PI Haiya2,3, CAO Li1, HUANG Zhen1, GUO Wenlong2, FENG Jiwen2,3, LIU Chaoyang2,3,*()   

  1. 1. School of Electrical and Electronic Engineering, Wuhan Polytechnic University, Wuhan 430023, China
    2. State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China
    3. University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2024-03-18 Published:2024-12-05 Online:2024-04-16
  • Contact: * Tel: 027-87199686, E-mail: chyliu@apm.ac.cn.

Abstract:

Dissolution dynamic nuclear polarization (dDNP) involves polarizing the sample under microwave irradiation at a low-temperature and strong-magnetic field, dissolving it by solvent of high-temperature and high-pressure, then injecting it rapidly into an NMR/MRI for detection. The dissolution system serves as a pivotal component in the dissolving and injecting process, with its performance directly affecting the melting and transfer efficiency and the high polarization retention. We present an automated dissolution system using a dual-loop proportional-integral-derivative (PID) control algorithm that can reach the target pressure of ~1.7 MPa after 9 min and control the internal pressure within 1.5%. The system can dissolve a solid sample of -271 ℃ in the self-developed 5 T dDNP polarizer and transfer it to the 7 T NMR system at a distance of 11.2 m for detection in 4 s, yielding a 9050-fold enhancement of 13C NMR signal of sodium [1-13C]-pyruvate at the solvated state. In summary, this work developed an automated dissolution system that simplifies the operation steps, ensures detection consistency, and improves experimental safety.

Key words: dissolution dynamic nuclear polarization, double-loop PID control algorithm, dissolution system, high temperature and high pressure

CLC Number: