FLOW INJECTION METHODS FOR THE DETERMINATION OF PESTICIDES IN NATURAL WATER SAMPLES USING CHEMILUMINESCENCE / SPECTROPHOTOMETRIC DETECTION BY MUHAMMAD ASGHAR DEPARTMENT OF CHEMISTRY UNIVERSITY OF BALOCHISTAN, QUETTA PAKISTAN 2018 FLOW INJECTION METHODS FOR THE DETERMINATION OF PESTICIDES IN NATURAL WATER SAMPLES USING CHEMILUMINESCENCE / SPECTROPHOTOMETRIC DETECTION Being a thesis submitted for the degree of Doctor of Philosophy In the University of Balochistan By Muhammad Asghar Supervisor: Dr. Mohammad Yaqoob, Professor Co-Supervisor: Dr. Abdul Nabi, Professor DEPARTMENT OF CHEMISTRY UNIVERSITY OF BALOCHISTAN, QUETTA PAKISTAN 2018 January 2018 Author’s Declaration I Muhammad Asghar hereby state that my PhD thesis titled “Flow injection methods for the determination of pesticides in natural water samples using chemiluminescence / spectrophotometric detection” is my own work and has not been submitted previously by me for taking any degree from this university, UNIVERSITY OF BALOCHISTAN, QUETTA or anywhere else in the country/world. At any time if my statement is found to be incorrect even after my graduate the university has the right to withdraw my PhD degree. Name of Student: Muhammad Asghar Date: January 2018 i Plagiarism Undertaking I solemnly declare that research work presented in the thesis titled “Flow injection methods for the determination of pesticides in natural water samples using chemiluminescence / spectrophotometric detection” is solely my research work with no significant contribution from any other person. Small contribution/help wherever taken has been duly acknowledged and that complete thesis has been written by me. I understand the zero-tolerance policy of the HEC and UNIVERSITY OF BALOCHISTAN, QUETTA towards plagiarism. Therefore, I as an author of the above titled thesis declare that no portion of my thesis has been plagiarized and any material used as reference is properly referred/cited. I undertake that if I am found guilty of any formal plagiarism in the above titled thesis even after award of PhD degree and that HEC and the University has the right to publish my name of the HEC/University Website on which names of students are placed who submitted plagiarized thesis. Student / Author Signature: ____________ Name: Muhammad Asghar ii Certificate of Approval This is to certify that the research work presented in this thesis entitled “Flow injection methods for the determination of pesticides in natural water samples using chemiluminescence / spectrophotometric detection” was conducted by Muhammad Asghar under the supervision of Dr. Mohammad Yaqoob, Professor and Co-supervision of Dr. Abdul Nabi, Professor Department of Chemistry, University of Balochistan, Quetta. No part of this thesis has been submitted anywhere else for any other degree. This thesis is submitted to the Department of Chemistry, University of Balochistan, Quetta in partial fulfillment of the requirement for the degree of Doctor of Philosophy in Field of Chemistry (Analytical / Environmental Chemistry), Department of Chemistry, UNIVERSITY OF BALOCHISTAN, QUETTA. Student Name: Muhammad Asghar Signature ________________ Dr. Mohammad Yaqoob, Professor Signature ________________ Supervisor Chairperson Signature ________________ Department of Chemistry University of Balochistan iii UNIVERSITY OF BALOCHISTAN, QUETTA DEPARTMENT OF CHEMISTRY CERTIFICATE This is to certify that Muhammad Asghar was registered for PhD degree program (Registration No. 1998/UB–2014/R–274, dated May 31, 2014) in the Department of Chemistry, University of Balochistan. He has successfully completed 18 and 32-hour credit course work and laboratory/research work respectively on “Flow injection methods for the determination of pesticides in natural water samples using chemiluminescence / spectrophotometric detection”. He may be allowed to submit his thesis on the topic mentioned above to the University of Balochistan for the fulfilment of PhD degree. Dr. Mohammad Yaqoob, Professor Dr. Abdul Nabi, Professor Supervisor Co-Supervisor iv ACKNOWLEDGEMENTS I would like to thank my research supervisor Dr. Mohammad Yaqoob, Professor, and Co-supervisor, Dr. Abdul Nabi, Professor, Department of Chemistry, for their guidance, patience, assistance and encouraging me during my PhD studies at the University of Balochistan and it is real honor for me to work with them. I would like to acknowledge my appreciation to Dr. Manzoor Iqbal Khattak, Professor & Chairperson, and Dr. Masood Ahmed Siddiqui Professor and Dean Faculty of Basic Sciences for their support, interest and providing the facilities at the Department of Chemistry, University of Balochistan, Quetta. I gratefully acknowledge the financial support provided by the Higher Education Commission, Islamabad (Grant number 20–640/R&D/06) for the conduct of this research at the Department of Chemistry, University of Balochistan, Quetta, and the Directorate Higher Education and Technical, Govt. of Balochistan, for study leave and moral support. The author acknowledges Professor Paul J. Worsfold and his research group, School of Geography, Earth and Environmental Sciences, Plymouth University, Plymouth, PL4 8AA, United Kingdom for providing 8-hydroxyquinoline immobilized resin. I am also thankful to all of those mentioned above, encouraging me during the research work and in writing of this thesis and Department of Chemistry, University of Balochistan for awarding me a chance to pursue the PhD degree. v Summary of the Thesis submitted for PhD degree by Muhammad Asghar On Flow injection methods for the determination of pesticides in natural water samples using chemiluminescence / spectrophotometric detection In recent years, the increasing number of pollutants being detected in surface water has raised concern about the contamination of water resources. Pesticides contamination of soil, food and waters has become a serious problem. Pesticides are widely used for the control of insects, fungi, bacteria, weeds, nematodes, rodents and other pests. However, despite their many merits, pesticides are some of the most toxic, environmentally stable and mobile substances in the environment. Their excessive use has deleterious effects on humans and the environment; their presence in food is particularly dangerous. Pesticide exposure can cause a variety of adverse health effects. These effects can range from simple irritation of the skin and eyes to more severe effects such as affecting the nervous system, mimicking hormones causing, reproductive problems and cancer. Strong evidence also exists for other negative outcomes from pesticide exposure including neurological defects, birth defects and neuro–developmental disorder. Pesticides are categorized into four main substituents: i) herbicides, ii) fungicides, iii) insecticides and iv) bactericides. In 2006 and 2008, the world used approximately 5.2 billion pounds of pesticides with herbicides constituting most of the world pesticide use at 40% followed by insecticides and fungicides with totals of 17 and 10% respectively. Therefore, the developments of simple and sensitive methods for the monitoring of pesticides are of great importance for the purpose. Chemiluminescence (CL) is defined as the electromagnetic radiation (ultraviolet, visible, or infrared) produced when a chemical reaction yields an electronically excited intermediate or product. The light intensity is directly related to the analyte concentration, thus allowing precise and sensitive quantitative analysis. The main attractions of CL for vi biochemical analysis show excellent sensitivity over a wide linear range and low limits of detection. There are many inorganic and organic chemical reactions that produce CL in the liquid phase and some of these CL systems are luminol, lucigenin, morphine, codeine, pyrogallol, acridinium esters, acidic potassium permanganate and tris(2,2/-bipyridyl) / Ruthenium(II). Luminol, lucigenin, tris(2,2 –bipyridyl) Ruthenium(II), KMnO4 and cerium(IV) sulfate are the most commonly employed CL reagents and find wide applications in analytical chemistry and chemical analysis. Transition metals in uncommon oxidation states such as silver(III), copper(III) and nickel(IV) have been exploited in the CL systems as oxidizing agents. Flow injection analysis (FIA) is based on the injection of a small volume of liquid sample into a moving non-segmented continuous carrier stream of a suitable liquid. The injected sample becomes a part of a continuously moving stream and forms a zone. The processed sample carrying stream is then finally transported towards a detector that continuously records the absorbance, emission, electrode potential or other physical parameter. This thesis concerns research work in the area of FIA in conjunction with CL and UV-Visible spectrophotometric detectors for the determination of pesticides in natural water samples. The work presented in this thesis is divided in ten chapters. The first chapter is devoted to the knowledge on the pesticides, its classification, toxicology, handling of water samples, luminescence, CL and its reagents with their analytical applications related to pesticides analysis in natural water samples. The FIA with its basic components and analytical applications are also presented in tabulated form. The second chapter describes CL instrumentation including a brief introduction and characteristics of photomultiplier tube (PMT), continuous flow methods, glass spiral flow cells and a test method for the determination of manganese(II) using luminol– diperiodatoargentate(III)