▎ 摘　　要

NOVELTY - Preparation of magnetic nanocomposite material comprises adding graphene oxide, ferric chloride hexahydrate and ferrous chloride tetrahydrate in alkaline solution to prepare magnetic graphene oxide, and adding graphene oxide and ethyl orthosilicate in ethanol to prepare magnetic solid phase extraction adsorbent silicon dioxide modified magnetic graphene oxide. USE - The method is for preparing magnetic nanocomposite material used for detecting trace heavy metal ion comprising chromium ion (Cr (III)), cobalt ion (Co (II)), nickel on (Ni (II)), copper ion (Cu (II)) cadmium ion (Cd (II)), lead ion (Pb (II)) and/or silver ion (Ag (I)) in environmental water sample comprising bottled mineral water, well water and sewage treatment plant water (claimed). ADVANTAGE - The method optimizes parameters for extraction and desorption, establishes magnetic solid phase extraction-inductively coupled plasma mass spectrometry combined analys, is simple and fast, and has high adsorption capacity, low detection limit, high sensitivity, good linearity, high recovery rate, and small consumption of organic solvent and adsorbent.