Heteroatomic Fe-ZSM-5Based Sono-fenton Reaction For Sample Pre-treatment In Analytical System

The traditional sample pretreatment methods remain ‘bottleneck’problems including consumption of harmful reagents, cumbersomeoperating procedure, secondary pollution and so on. However, with theprogress of the public’s living quality and health consciousness, in orderto indicate the human physiological and biochemical status, it is essentialfor clinical analysis of trace metal elements and other targetedcomponents in real metabolitic samples. Therefore, novel samplepretreatment method is in urgent demand with advantages being simple,efficient, green and pollution-free.Heteroatomic Fe-ZSM-5zeolite particles based heterogeneousFenton reaction has the merits of high catalytic decomposition activity,less consumption of reagents, evitable precipitation of free iron ion,reusable and so on. In addition, synergic ultrasonic assistance with Fentonreaction can significantly improve the catalytic reaction speed anddegradation efficiency.Therefore, in this thesis, Fe-ZSM-5zeolite based ultrasonic assistedheterogeneous Fenton reaction technique was firstly developed for a featured “green and efficient” real biological sample pretreatment. Thestudies are mainly as the following aspects:(1) Hydrothermal synthesis of Fe-ZSM-5zeolite in lab and itscatalytic activity: The characterization data such as SEM, XRD, XRF,EPR, etc, demonstrated that MFI type Fe-ZSM-5zeolite have beensuccessfully prepared wih uniform grain, microporous/mesoporous/macroporous structure and6.27%content of Fe dispersed into theframeworks. The OH and O2-were detected in the reaction systemthrough the EPR technique. And the addition of heteroatomic catalystcould obviously increase the generation of free radicals.(2) The feasbility of ultrasonic assisted Fe-ZSM-5Fentonreaction system for biological sample pretreatment: The ultrasonicassisted condition could promote sample pretreatment. SDS-PAGE andCD measurements were used to detect that ultrasound could contributethe expansion of peptide chain of the protein which subsequentlyfacilitate degradation process and the effect of direct ultrasound wasbetter.(3) Optimization of blood sample pretreatment conditionsunder direct ultrasonic assisted Fe-ZSM-5Fenton reaction:3mL3.0×10-5moL/L BSA solution (pH=3) was exposed with H2O2concentration=51.69mmoL/L, the amount of Fe-ZSM-5catalyst=3.33g/L for15min reaction time. The main protein of blood including Hb and FIB included could be degraded under the optimal pretreatmentconditions.(4) The ultrasonic assisted Fe-ZSM-5Fenton pretreatment forreal blood samples collected from clinical patient volunteers for totalarsenic determination: After the blood sample was diluted by20times(v/v), it was pretreated under recommended conditions given in (3). Itwas found that the targeted arsenic was immobilized on the Fe-ZSM-5using the IR spectra. The arsenic could be transferred into the aqueoussolution media and subsequently detected by HG-AFS method. Therelated arsenic recovery was between88.9%~96.7%, RSD <10%.