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A magnetic separation-based immunosensor for deoxynivalenol assay, coupled with a nano-affinity cleaning up for instrumental confirmation, was developed. Maltose-binding protein with mimic epitope of DON was coupled to CdSe/ZnS quantum dot nanobeads for fluorescent reporter. Graphene oxide was linked with magnetic nanoparticles and protein G for immunomagnetic adsorbent. The magnetic separation of reporter could be inhibited by DON so the fluorescent remained in the solution indicates a good quantitative correlation to DON concentration. The DON separated by immune adsorbent can be cleaned up for instrumental confirmation. The optimized immunosensor showed results as follows: the linear range was in 0.3–3000 ng mL−1. The limits of detection (S/N = 3) were 0.50, 1.0, and 3.0 ng mL−1 in different backgrounds. The recoveries for DON-spiked samples range from 78.7% to 88.5%. Both results of UPLC-MS/MS based on affinity column purification and coupled with nano-affinity cleaning up showed a good agreement with the current immunosensor.

In this work, highly uniform cubic germanium/husk-derived graphene nanocomposites (Ge/GR nanocubes) were synthesized via facile chemical methods. The structure and composition of the prepared Ge/GR nanocubes were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX) etc., confirming a homogeneous distribution of Ge nanocubes (30–90 nm in size) on few-layered graphene nanosheets. Further investigations showed that the prepared novel Ge/GR nanocubes could combine both photocatalytical advantages of Ge nanocubes and graphene nanosheets for Sudan I purification with optimal removal efficiency of 98.1% in wide concentration range (0.25–4.0 mg/mL) at mild conditions. The prepared high active photocatalyst can be used for five consecutive runs. By using husk-derived graphite microcrystalline as the starting material of graphene, the cost of the Ge/GR nanocubes was obvious decreased, which fosters it a high active, low cost and durable candidate for azo dye removal in water.

An efficient separation and purification method by microwave-assisted extraction coupled with counter-current chromatography and preparative liquid chromatography was developed. The extracts obtained from microwave-assisted extraction were rapid separated with counter-current chromatography, and then the fractions were further purified with preparative liquid chromatography. With this method, six furocoumarins including xanthotoxin, bergapten, columbianetin acetate, osthole, isoimperatorin and columbianadin can be obtained from original Angelica Pubescentis Radix samples within total time of 450 min. Their purities were 98%, 98%, 99%, 99%, 99% and 99% respectively, as determined by HPLC. The structures of these compounds were identified by 1H NMR and MS spectroscopy. The proposed method was economic, rapid and effective, and it can be used to prepare and purify targets from natural products.