Lysine is one of the essential amino acids for human body

and its imbalance is a major cause to anemia

aging process

leukemia cell proliferation and tumor growth. Therefore

its monitoring is dominative to the prevention the disease progress and guidance to the clinical treatment. However

traditional in-hospital detection methods

such as colorimetry and fluorometric

often suffer the disadvantages of high cost and long time-consuming. These drawbacks show a difficulty in the home-in and dairy monitoring for the lysine regulation in body. In this study

we have proposed an ultrasensitive microchip-based portable device to achieve the onsite and precise determination of lysine within only 10 s. This microchip was functionalized through constructing a center-concave nanosheet of core-shell WO

3

@Prussian blue (WO

3

@PB) to remarkably strengthen the generation and transfer of the detection signal. In this special architecture

the core WO

3

nanosheet can be exposed at the center region of this nanocomposite to effectively promote the enzymatic oxidation

while the PB shell enables to strongly reduce the H

2

O

2

produced by the enzymatic reaction. Under above synergetic effects

a handheld device was designed to support the plug-and-play microchip

which performed an outstanding accuracy for the lysine detection in blood.