TPED Functionalized Materials Colorimetric Detect Copper Ions In Aqueous Solution

As an important trace element to living organisms,copper ion plays an essential role as cofactor for numerous enzymes that participates in a variety of physiological and pathological events.In low concentration,it is requisite to maintain normal functions of human body.However,it would become highly toxic under overloading condition,leading to illness like chronic disease(such as diabetes,cardiovascular disease and atherosclerosis),neurological disorders(like Alzheimer's disease),and even cancer.Studies also demonstrated that copper is required for oncogenic mitogen-activated protein kinase signaling and tumorigenesis.Given the versatile functions involved in copper metabolism,restricted regulations have been set to limit the concentration of Cu2+by official organizations among the world on account of it toxicity.In drinking water,for instance,the World Health Organization(WHO)has recommended 1.5 mg/L of Cu2+as the maximum acceptable concentration while the maximum allowable level of Cu2+ ion has been set at about 20 ?M by U.S.Environmental Protection Agency(EPA).Up to now,measurement of biological and environmental Cu2+ concentration can be realized using various instrumental techniques,which include stripping voltammetry,atomic absorption spectrometry,inductively coupled plasma mass spectrometry,and so on.Although those methods have been demonstrated with good accuracy,they also involve in inescapable drawbacks like high cost,sophisticated pretreatment,requirement of professional operation,and no accessibility to in-filed analysis.Therefore,a simple,rapid and convenient method for easy measurement of copper ions is of particular importance.As an attractive technology,colorimetric sensors have been widely explored due to merits of easy fabrication,low-cost,ease of operation,convenient data acquisition and portability for in-field detection of analytes including glucose,amino acids,toxic gas and heavy metals.In this thesis,we have fabricated diamine functionalized filter paper and hollow mesoporous silica sphere to absorb copper ion and detected the concentration after adding cupron through colorimetric method.The Thesis includes two parts:(1)A simple,cheap and effective functional paper has been fabricated to absorb and detect Cu2+ with good sensitivity and selectivity.Using commercial cellulose filterpapers as substrate,Magneliphase structure of Ti6O11 wascoated at the surface to serve as intermediate linker to modify N-[3-(Trimethoxysilyl)propyl] ethylenediamine for Cu2+ binding.Under optimized conditions,i.e.at 50 ? with electromagnetic stirring,the functional paper can absorb Cu2+with high-performanceand gave clear color response using cupron aschromogenic agent.The concentration-dependent colorimetric response(?B value)matches well with the exponential linear curve under dynamic absorption conditions,where the linear range was from 33.6nM to 39.8?M and the detection limit was measured to be about 33.6 nM.Measurement of a group of possible interfering ions and spiked real water samples demonstrated the good selectivity of the proposed paper.Furthermore,the performance can be further improved using microwave irradiation,where a lower detection limit of 16.8 nM was achieved within a wider linear range from 16.2 nM to 0.98 mM.The reaction time can be shortened to20 min to reach final equilibrium and the saturated absorption amount of Cu2+ for a single piece of paper(diameter=1.0 cm)was as high as 4.5169 ?g/cm2.The proposed functional papers would offer an effective alternative for potential absorption and determination of copper ions in real applications.(2)An efficient,reliable and recyclable functional material was prepared to absorb and determine Cu2+ using N-[3-(Trimethoxysilyl)propyl] ethylenediamine modified mesoporous hollow shells(HMS-NHs).By stepwise coating with mesoporous silica at highly mono-dispersed PS spheres,successive removal of template materials,and final modification with functional diamine groups,higher absorption capacity of about138.58 mg/g was realized.After optimization of preparing conditions including size of PS templates,thickness of SiO2 layers,and pore size of the shell,and etc,as-prepared HMS-NHs gave clear colorimetric response after color development using cupron solution.Selectively measure Cu2+ in a wide concentration ranges from 0.025 to 49 ??was observed with a detection limit around 25 nM(3?).More importantly,it can also be regenerated by treating with hydrochloric acid and maintain high efficiency upon repeated use for at least 10 times.Extensive investigation demonstrated that the HMS-NHs can be used as not only high-performance absorption materials but also sensitive sensor for Cu2+,which offer a promising alternative for potential removal and detection of copper ions in real applications.