In the field of food safety monitoring, the detection of non-intentionally added substances (NIAS) in food contact materials (FCMs) has garnered growing concern, particularly due to the potential nephrotoxicity (kidney damage caused by exposure to toxic agents) and carcinogenicity of chloropropanol contaminants such as 3-monochloropropane-1,2-diol (3-MCPD). Although gas chromatography–mass spectrometry (GC-MS) remains the standard analytical tool, its complex derivatization procedures, lengthy analysis times, and limited adaptability for on-site detection hinder its application in high-throughput or real-time screening.

To address these challenges, Chengrong Qin and Shuangquan Yao, Guangxi University, China, and colleagues developed a Molecularly Imprinted Nanochip Analytical System (MNAS).

This system combines a density functional theory (DFT)-guided molecular recognition interface with a quartz crystal microbalance (QCM), a sensor that detects small mass changes by shifts in vibration frequency. The researchers designed the molecularly imprinted polymer (MIP) interface using pre-organized hydrogen bonding between 3-MCPD and methacrylic acid (MAA), and confirmed the mechanism with variable-temperature Fourier-transform infrared spectroscopy (VT-FTIR) and theoretical modeling.

Unlike conventional methods, the MNAS directly translates molecular binding into distinct frequency shifts, generating precise electrical signals without derivatization. It achieved a detection limit of 0.006 μM—much lower than that of GC-MS (2.2 μM)—and reduced analysis time by more than 75%. This represents the first in situ, derivatization-free, and rapid quantitative analysis of 3-MCPD in paper-based FCMs using a MIP-QCM platform, overcoming long-standing selectivity challenges and providing a scalable tool for monitoring non-intentionally added substances (NIAS) in food packaging safety.

• Functional Nanosensor-Integrated System Based on Molecularly Imprinted Quartz Crystal Microbalance for Rapid In Situ Detection of 3-Chloro-1,2-Propanediol in Paper-Based Food Contact Materials
  Jinwei Zhao, Yi Xie, Haodong Guo, Jiali Pu, Qiuping Wu, Shuangquan Yao, Chen Liang, Shiming Zhang, Baojie Liu, Caoxing Huang, Chengrong Qin
  Aggregate 2025
  https://doi.org/10.1002/agt2.70111