Illegal drug smuggling has long been a global concern and posed a serious threat to human health. Chinese researchers developed a rapid screening of trace volatile and nonvolatile illegal drugs by miniature ion trap mass spectrometry, realizing rapid on-site detection of illegal drugs in mixtures and the minimum detectable quantity reach to 50 picograms for fentanyl.

The study was conducted by a research group led by Prof. LI Haiyang from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences in collaboration with Yunnan Police Officer Academy, and Drug analysis and Drug Control Technology Key Laboratory of the Ministry of Public Security.

The group has been working on rapid detection of illegal drugs. Acetone assisted photoionization was introduced and a temperature-resolved thermal desorption sampling strategy was developed to distinguish illegal drug mixtures in 10 minutes, and 27 kinds of illegal drugs were detected as well.

However, the illegal drugs usually have a distinct boiling point, and nonvolatile illegal drugs have low detection sensitivity while the volatile illegal drugs have a short detection period. In order to faster identify the illegal drug mixtures with big difference of boiling point, flash-thermal-desorption was used to thermal desorb the sample and its focal temperature can reach to 290 ℃ in 2.5 seconds, which could achieve more than 60 times improvement in sensitivity compared with the previously reported miniature ion trap for nonvolatile drugs.

The synchronized purging and ion injection with DAPI could accurately control the time interval along with desorption, gas purging, ionization and ion injection, and the sample utilization ratio increased more than 5 times. Ten kinds of mixing drugs with boiling point difference of 300 ℃ could be simultaneously identified within 3 seconds.

The study entitled "Rapid Screening of Trace Volatile and Nonvolatile Illegal Drugs by Miniature Ion Trap Mass Spectrometry: Synchronized Flash-Thermal-Desorption Purging and Ion Injection" was published in Anal. Chem.

Mass spectrometer applied at a frontier inspection station in Yunnan province. (Image by DICP) 

Schematic diagram of the synchronized flash-thermal-desorption purging and ion injection and the on-site identification of fentanyl capsule. (Image by WANG Weimin)  

During the development process, the mass spectrometer was used in multiple Frontier Inspection Stations in Yunnan provinces, such as Mukang Frontier Inspetion Station in Dehong Autonomous Prefecture, Qinglongchang Frontier Inspection Station in Yuxi city. 37 kinds of illegal drugs’s mass spectrum have been added into the identification database and valuable experience was gained for the study of ion trap mass spectrometry in drug detection.

The above research was supported by the National Natural Science Foundation of China, and it is dedicated for the 70th anniversary of DICP.