الفهرس 
Characteristics of molecular imprinted polymersOnly 14 pages are availabe for public view
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Abstract
This thesis deals with the preparation of molecular imprinted polymers (MIPs) with high cross-linking containing memory site for cholesterol to be used in cholesterol adsorption from available commercial palm oils and human blood sera. In which the hydrophilic poly (HEMA) interacts with hydrophobic entities like cholesterol in the presence of EGDMA and the polymerizations were initiated by ionizing γ -radiation. All the synthesized MIPs and NIPs were characterized using FTIR, SEM and TGA. Swelling capacities and gel content were evaluated. Bio-applicability of the prepared materials were studied and evaluated from available commercial oils and human blood sera which was the main purpose of this study. Biocompatibility of MIP was verified by testing the in vitro cytotoxicity.
The results obtained in this thesis can be summarized in the following:
A. Preparation of Cholesterol imprinted poly-HEMA (MIPs) and Non- imprinted polymers (NIPs)
1. The polymers that irradiated with low doses of gamma ray (less than20kGy) became liquid like. These polymers lost more than half of their volume during the drying process but the polymers irradiated with doses more than 20kGy became transparent and gel-like. The degree of the collapse and the transparency of the polymers decreased with increasing doses of irradiation.
2. The effect of irradiation dose on the gelation of MIP and NIP at different monomer concentration was investigated. The gel content increased by increasing monomer concentration (HEMA) and the gel content of cholesterol imprinted polymers (MIPs) found to be lower than that of non- imprinted polymers (NIPs).
3. The samples irradiated at 20kGy were later used for cholesterol removal experiments after the percent of gelation to insoluble network increased with increasing irradiation dose, reached approximately at a total dose of 20kGy.
4. The swelling percent of the synthesized polymers at different cross-linker concentration and different monomer concentrations were investigated. Both MIPs and NIPs showed a maximum degree of swelling when the cross-linker concentration was 1wt% .The degree of swelling decreased with the increase of monomer concentration (HEMA) in both MIPs and NIPs.
5. It was found that the swelling degree (EDS) of cholesterol imprinted polymers (MIPs) is higher than that of non- Imprinted polymers (NIPs).
6. It was found that the MIP exhibited a maximum chemical stability toward (chloroform /ethanol/acetic acid) and (methanol/acetic acid).
B. Cholesterol leakage studies
In this part, cholesterol as a template molecule along with the rest of homo-polymers was removed by long term extraction process and the results were summarized as follows:
1. It was found that that (ethanol: chloroform: acetic acid =1:3:1) has the highest eluting and cholesterol release percent (75%).
2. It was found that MIPs with EGDMA (1wt %) possess higher percent of cholesterol releasing capacity compared to the other.
C. Cholesterol binding and Adsorption studies
In this part, Adsorption of cholesterol template on the MIPs and NIPs were carried out using batch-wise adsorption method, where the MIPs and NIPs were placed in aqueous solutions with different concentrations of cholesterol.
The results can be summarized as follows:
1. The adsorption of cholesterol by MIP increases by time to reach its maximum at 5.5 hours.
2. It was very fast at the initial 2 hours then a slight increase was observed until equilibrium was obtained.
D. Characterization
1. The thermal stability of MIPs and NIPs over a wide range of temperature had been confirmed by thermo-gravimetric analysis (TGA) which is suitable for its practical uses.
2. FTIR indicated that cholesterol templates were removed from MIPs, which therefore presents an advantage for the study of cholesterol adsorption.
3. The surface morphology and fundamental physical properties of the synthesized MIPs were investigated by using Scanning Electron Microscope (SEM) which showed that NIPs are inert with no pores, confirmed that cholesterol template deposited and adsorbed by eluted MIPs. A porous structure appears which is an evident that these pores are the regions of cholesterol permeation and interaction sites of cholesterol as a template. The image of MIP after elimination of cholesterol demonstrates the pores which tend to be connected to each other.
E. Selectivity studies
In this part, a range of structural analogues of cholesterol (2mL cholesterol and testosterone) were added individually to MIPs. The samples were shaken at room temperature for 24 hours then the MIPs and NIPs were removed from the solution and the concentration of cholesterol and testosterone in the supernatant was analysed.
The results can be summarized as follows:
1. Cholesterol imprinted polymers (MIPs) have higher binding capacities for cholesterol than for testosterone.
2. MIPs bond cholesterol is more selective than steroid analogues.
F. Adsorption of sterol from commercial samples of palm oils
In this part, MIPs were suspended individually in palm oil solution and human blood sera then they were recovered from the solutions and the amount of adsorbed cholesterol was estimated.
The results can be summarized as follows:
1. MIPs had a higher binding capacity for cholesterol, when added in blood sample.
2. It was found that the cholesterol recovery (%) increased with increasing initial cholesterol concentration in blood sera.
3. It was found that cholesterol from palm oil was adsorbed by eluted MIPs.
G. Biocompatibility tests
In this part, Biocompatibility of verified by testing in vitro cytotoxicity by investigating the possible anti-proliferative property of MIPs against Ehrlich ascites tumor cell line (EAC) through MTT assay and exclusion assay of tyrpan blue.
The data summarized in this part indicates that:
1. The percent of viability of EAC cell decreasing by increasing the incubation time with MIPs after staining with tyrpan blue.
2. 25% of MIP showed less toxicity to EAC cells, however by increasing the concentration of MIP the cytotoxicity increased.