Metal-Organic Frameworks As Sorbent For The Application And Enrichment Of Disease Biomakers In Breath

Human breath can regarded as the headspace gas blood,and is expelled from the body through alveolar exchange.Thus,human breath can reflect the endogenous metabolism of the human body.In recent years,with the continuous development of non-destructive medical diagnosis,exhaled breath analysis has the potential for early diagnosis and large-scale screening of clinical diseases due to its non-invasiveness,painlessness and convenience.However,the matrix of human exhaled breath is complex,and the concentration of biomarkers in exhaled breath is low(10^-1212 mol·L^-1-10^-99 mol·L^-1),it is difficult to achieve accurate and sensitive detection of biomarkers in exhaled breath.Therefore,the actual sample requires pretreatment to achieve the concentration required for analytical separation.Solid-phase microextraction and thermal desorption as sample pretreatment technologies have the advantages of environmental protection,easy operation,economy and practicality,and are widely used in many fields.The core of these two technologies is the adsorbent used to enrich the target,because the type and nature of the adsorbent determine the sensitivity and selectivity of the method.Metal-Organic Frameworks?MOFs?,as a new type of porous materials,have many unique properties,such as rich variety,post-modification,good stability,adjustable porosity,large specific surface area,etc.Applications in the field of extraction and thermal desorption have many advantages.This article aims to explore the preparation of MOFs and MOFs coatings,and to study the enrichment of biomarkers in exhaled breath of several major diseases by MOFs as adsorbents.The specific research contents are as follows:1.Using three MOF materials?ZIF-7,MOF-5,UiO-66?as adsorbents,in order to compare the adsorption capacity of two biomarkers?acetone and isopropanol?in the exhaled breath from diabetics,and the synthesized three MOF were characterized by scanning electron microscope,X-ray diffraction,Fourier transform infrared spectroscopy,and thermogravimetric analysis.The results show that UiO-66 has the best adsorption effect on acetone and isopropanol,and its adsorption capacity is 2.4-4.2 times better than ZIF-7 and2.2-3.5 times betrer than MOF-5.Finally,we used UiO-66,which has the best adsorption efficiency,as an adsorbent for the enrichment and detection of acetone and isopropanol in the exhaled breath of diabetic patients.The mechanism of adsorption were discussed.2.MIL-101?Cr?was post-amino modified,and prepared MIL-101?Cr?-NH₂ solid phase microextraction coated fiber.The extraction conditions were optimized,and the self-made MIL-101?Cr?-NH₂ extraction fiber was used to enrich biomarkers in the exhaled breath of lung cancer patients.Due to the post-modification of the amino group,MIL-101?Cr?-NH₂ has a porous structure and a higher specific surface area.The experimental results show that the enrichment efficiency of MIL-101?Cr?-NH₂ extraction fiber is higher than MIL-101?Cr?and commercial extractive fibers.3.A polyaminophenyl layer is grafted on a stainless steel wire fiber surface by means of the diazoniuminduced anchoring process,and then the MOF-808 was coated on the stainless steel wire fiber by covalent bonding.It was characterized by scanning electron microscope,X-ray diffraction,Fourier transform infrared spectroscopy,and thermogravimetric analysis.The solid-phase micro-extraction coating prepared by the covalent bonding method has the characteristics of excellent stability and long lifetime.Finally,the prepared MOF-808 coated fiber was successfully used for enrichment of biomarkers in the exhaled breath of breast and gastric cancer patients by solid-phase microextraction,and the adsorption mechanism was discussed initially.