Using the shrink-assembled liquid three dimensional (3D) hot spot matrix as a microreactor, a new method for quantitative detection of blood drug concentration by surface-enhanced Raman spectroscopy (SERS) was developed by researchers led by Prof. Yang Liangbao and Prof. Wang Hongzhi from the Hefei Institutes of Physical Science (HFIPS) of the Chinese Academy of Sciences (CAS), with high stability and sensitivity.