الفهرس 
Introduction and Aim of the workOnly 14 pages are availabe for public view
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Abstract
This thesis was divided into four chapters, each of which can be summarized:
Chapter I: Introduction
The main points of this chapter can be recapitulated as follows:
A) General introduction about pharmaceutical drugs and their effects on the human body. Also, it includes the importance and the main advantages of determination and monitoring of pharmaceutical drugs (RIV, AMI, CP) by different electrochemical techniques. B) Aim of work
Chapter II: Literature Survey
This chapter includes a full literature survey about different electrochemical methods for the determination of various pharmaceutical drugs that depend on imprinting techniques.
The different points that have been concerned in this chapter.
1. The importance, effects, and determination methods of different pharmaceutical drugs (RIV, AMI, CP)
2. Different technologies such as gas chromatography (GC), high-pressure liquid chromatography (HPLC), and capillary electrophoresis (CE) methods have been employed for the recognition and determination of these drugs.
3. Several approaches for the preparation of imprinting polymers include covalent and non-covalent techniques.
4. Different electrochemical techniques for the determination of different drugs.
5. The application of determination and recognition of different pharmaceutical drugs by using electrochemical methods that depend on imprinting techniques.
Chapter III: Experimental
The sources of different chemical reagents and instruments apparatus were stated. These instruments employed for the investigation of imprinted polymers are described including Fourier transform infrared, scanning electron microscope, and energy dispersive X-ray analysis. Moreover, this chapter describes the processing and details of the analytical methods which have been done in this work as follows:
1- Preparation of different solutions such as RIV, AMI, CP, and buffers.
2- Preparation of molecular imprinted polymers for RIV, AMI, and CP as different templates. Methacrylic acid (MAA) and acrylamide (AM) are monomers that were used for the preparation of these polymers in the presence of initiator (potassium persulfate), cross-linker (EGDMA), and template molecules (RIV and/or AMI and/or CP). After that, the template molecules were extracted from the polymeric matrices using methanol/acetic acid (10%). Moreover, non-imprinted polymer (NIP) was obtained using identical processes, but without the template molecules.
3- Fabrication of different voltammetric and potentiometric sensors using glassy carbon electrode (GCE). For voltammetric measurement, the surface of the GCE was modified using the prepared polymers (MIP or NIP) in the presence of graphene oxide (for enhancement the conductivity) by using DROP coating method. While in the different potentiometric sensors, the imprinted polymers were deposited as one layer after embedding in a plasticized polyvinyl chloride membrane on the surface of GCE.
4- Investigation of the different parameters (ex: pH, scan rate, leaching time, incubation time, response time...etc.) for the optimization of determination and recognition of different template molecules.
5- Pre-treatment of pharmaceutical tablets, urine samples, and real blood samples.
Chapter IV: Results and discussion
This chapter is divided into two parts:
Part 1: characterization and electrochemical determination of electro-inactive drugs (RIV)
The characterization of the prepared imprinted polymers for RIV was investigated by using SEM, AFM, EDX, and IR.
• In FT-IR spectra of un-leached MIP a significant band at 1672 cm− 1 was noticed, which was assigned to the stretching vibration of the benzene ring. The appearance of this band confirmed the sufficient immobilization of the RIV template on the polymeric matrix. The spectra of NIP and leached MIP elucidated several comparable bands. These results in the IR spectra not only reveal their similarity of the backbone structures but also emphasize totally leached of RIV molecules from the polymeric network.
• In energy dispersive spectrometer a unique signal for chloride was noticed in the un-leached MIP spectrum, which can be attributed to the presence of RIV.
• SEM and AFM images indicate that the roughness and porosity of the un-leached polymer surface were gradually elevated from 393.7 nm to 533.7 nm after the leaching process, and it’s a good indication for enhancement of the surface area.
Depending on the voltammetric and potentiometric techniques, the MIP was used for modification of the glassy carbon electrode and recognition of the RIV template after examining the different parameters (ex: pH, scan rate, leaching time, incubation time, response time...etc.) that effect on the determination of RIV. The potentiometric sensor showed an excellent linear range from 1.2 × 10− 9mol L− 1 to 1 × 10− 3mol L−1 and a relatively low detection limit (LOD = 2.4 × 10− 10 mol L− 1). Moreover, the Low standard deviation (2.6) was noticed indicating highly precise procedures. For the stability of the proposed potentiometric electrode, the potentiometric signals for this sensor retained 95.8% of its initial potential values after 6 weeks. On the other hand, the voltammetric sensor showed a linear relationship between differential pulse voltammetry signals and the concentration of RIVin in the range from (5.4 × 10− 11–3.1 × 10− 3 molL− 1) with a lower detection limit (2.3 × 10− 12 mol L− 1). Furthermore, it exhibited Repeatability (RSD=2.3%), high stability (4 weeks), and excellent selectivity. Moreover, the proposed sensors were utilized for the determination of RIV from real blood samples, and pharmaceutical tablets, the recovery values were in the range from 99.3% to 100.3% for both sensors.
Part 2: characterization and electrochemical determination of electro-active species (AMI, CP)
The imprinted and non-imprinted polymers of template molecules (AMI/CP) were confirmed by different analyses (FTIR, Elemental analysis, atomic force microscope, and scanning electron microscope). • In FT-IR spectra of un-leached MIP for AMI, significant absorption bands at wavenumbers of 3500, 1700, and 1250 cm-1 were assigned to the COOH, C=O stretching, and bending, respectively. Also, the presence of an absorbance band at 1557cm-1 belongs to pyrimidine. While, in FT-IR spectra of un-leached MIP for CP, significant absorption bands at 1650 cm-1 and 664 cm-1 were assigned to the C=O and C-S. These bands confirm the successful insertion of template molecules (AMI/CP) in the polymer during the polymerization process. Furthermore, there are similarities between the IR spectra of leached MIP and NIP which emphasizes that their backbone structures are the same and the complete removal of the template molecules. • The result of the element analysis showed that the high content of nitrogen in un-leached MIP (For AMI and/or CP) compared with leached MIP revealed the presence of an AMI and/or CP template in the polymeric matrix. • In SEM and AFM images, it was observed that the leached polymers have a relatively rough surface, compared with un-leached MIP, with uniformly distributed pores. The porosity and roughness of the imprinted polymers were sharply elevated after leaching the template molecules (AMI/CP). After modification of the surface of GCE by imprinted polymers, different parameters (ex: pH, scan rate, leaching time, response time...etc.) that affect the determination of template molecules (AMI/CP) were examined by voltammetric and potentiometric techniques. The potentiometric sensor for AMI showed an excellent linear range from 2.6 × 10-9 to 3.1 × 10-3 mol L− 1 and a relatively low detection limit (LOD = 1.4 × 10− 10 mol L− 1). Moreover, the Low standard deviation (3.6) was noticed indicating highly precise procedures. For the stability of the proposed potentiometric electrode, the potentiometric signals for this sensor retained 95.8% of its initial potential values after 5 weeks. While the potentiometric sensor for CP showed an excellent linear range from 2.9×10-9 – 4.2×10-3 mol L− 1 and stabilized quickly for all tested concentrations (< 5s). Moreover, it exhibits good selectivity, high sensitivity (LOD = 1.6 × 10− 10 mol L− 1), and excellent stability (4 weeks). On the other hand, the voltammetric sensor for AMI showed a linear relationship between differential pulse voltammetry signals and the concentration of AMI in the range from (3.7×10-11 - 1×10-3mol L− 1) with a lower detection limit (2.1 × 10− 12 mol L− 1). Furthermore, it exhibited repeatability (RSD=2.1%), high stability (3 weeks), and excellent selectivity. While the voltammetric sensor for CP showed an excellent linear range from 4.1×10-11 – 3.5×10-3 with a lower detection limit (2.5 × 10− 12 mol L− 1). Furthermore, the voltammetric sensor has high repeatability (RSD=2.6%), and excellent stability (5 weeks). Moreover, the proposed sensors were applied for the determination of template molecules (AMI/CP) in pharmaceutical and urine samples with recovery values in the range from 98.2% to 99.6%.