Department of Chemistry
Permanent URI for this communityhttps://repository.cuilahore.edu.pk/handle/123456789/14
Browse
3 results
Search Results
Item Detection of Heavy Metal Ions using a Composite of Graphene Oxide, Iron Oxide and Metal Organic Framework(Library Information Services COMSATS University Islamabad Lahore Campus, 2020-02-19) Farhan Nazir Ahmad; FA18-R06-005; Dr. Sara Riaz; LHR TP 6489Heavy metals are non-biodegradable, tend to accumulate in living organisms and cause serious health problems. Therefore, effective treatment of heavy metal ions in aqueous media is critical for public health. For selective and sensitive detection of Pb+2, Hg+2 and Cu2+, glassy carbon electrode was modified by a composite of Graphene oxide, metal organic framework and iron oxide. GO serves as backbone of MOF and iron oxide. It improves conductivity by enhancing electron transfer rate in matrix. Moreover, there are interactions between hydrophilic groups of GO and metal cations. GO, MOF and composite of GO-iron oxide was characterized by FTIR and XRD. The detection performance of electrode modified by composite of GO-MOF-iron oxide and GO-iron oxide was explored by EIS and CV. On introduction of MOF-5 to composite of GO-iron oxide, MOF-5 blocks active sites of composite and deactivate it, as MOF-5 hinders transfer of electron. While composite of GO-iron oxide shows excellent heavy metal ions adsorption, high capacitive current and better sensitivity as compared to composite of GO-MOF-iron oxide. This is all attributed to better electron transport properties, good electronic conductivity and large surface area of GO-iron oxide which lead to excellent catalytic response towards heavy metal ions.Item Growth of ZnO NanoFlakes on Flexible Carbon Based Transducer Surface for Electrochemical Sensing of Acetone(library Information Services CUI Lahore Campus, 2020-02-16) Seemal Mansoor; FA18-R06-026; LHR TP 5967; Dr. Sara RiazThe present study was concentrated to develop a rapid, electrochemical, selective, cheap and easy to use carbon cloth (CC) based assay for the quantitative and qualitative detection. CC was fabricated with a ZnO nanoparticles first and then with diazonium salt. This modified CC was then applied for the detection of acetone. FTIR, AFM and SEM was used to explore the chemical and physical characteristics of CC of before and after each modification. These results manifested that ZnO-nanoflakes and diazonium salt functionalization could increase the roughness of the CC surface that was advantageous to promote the interaction between CC and analyte to be detected. Linear sweep voltammetry and cyclic voltamogram were used for electrochemical analysis. The proposed electrochemical sensor was analyzed for various concentration of acetone. To validate the concept, the proposed sensor was assessed for higher concentrations of acetone in different ways. Among them, ZnO nanoflakes/ CC which was modified with diazonium salt showed better response (in acetone solution alone) than ZnO nanoflakes /modified CC (in the solution of diazonium salt and variable concentrations of acetone)Item Synthesis and Characterization of Dipyromethanes and Their Metal Complexes for Glucose Detection(library Information Services CUI Lahore Campus, 2020-02-16) Adeel Ahmed; FA18-R06-013; Dr. Sara Riaz; LHR TP 5964Glucose plays an active part in human body such as balancing the body in non-fortified feature, generating energy and improve memory enlargement. Blood glucose concentration is a universal benchmark of a patient’s fitness, particularly for threatening mark related with diabetes mellitus. Due to increased numeral of diabetic patients, various methodologies for glucose determination have been employed to assist precise and uninterrupted glucose detection. In present work, an advanced enzyme free electrochemical device has been proposed for glucose measurements. We intended to synthesize various derivatives of Dipyromethanes (DPM) via microwave assisted synthesis for the detection of Glucose. The synthesis of DPM is generally acid catalyzed reactions that occur in the existence of organic solvent dichloromethane (CH2Cl2). However, the problem of refinement and separation associated with conventional synthetic routs limits their synthesis and utilization in numerous fields. To avoid the lengthy and time consuming process of crystallization and separation we aim to further synthesize their transition metal complexes with Zn. The complexes of DPMs were purified via simple centrifugation. These DPM complexes were further drop casted onto carbon based electrodes (preferably glassy carbon electrodes) to study their electrochemical properties. For this purpose, the electrochemical biosensor was prepared by the modification of a freshly glassy carbon electrode surface with zinc-dipyromethanes complex. The spectral studies were done by UV-visible spectrophotometer and fluorescence spectrophotometer. The surface morphology and structure of the prepared complex were analyzed by AFM, FTIR, and XRD. The electrochemical characteristics of the complex were evaluated by CV and EIS. The results of CV (oxidation peak at 0.33V) indicated that zinc-dipyromethanes complex (Zn-DPM) can efficiently oxidize the glucose without any enzymes assistance and can further be used for glucose detection.