الفهرس 
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Abstract
Nanotechnology is an advanced and unconventional technique that involves the
science, engineering, and technology directed at the nanoscale. It incorporates particles of
the order of 1 billionth of a meter (10− 9 m) or as defined by the National Nanotechnology
Initiative (NNI) at sizes of roughly 1-100 nanometers. This technology has many
applications specifically in the medical field known as nanomedicine. In recent years,
nanomaterials have been the focus of research literature due to their potential impact in
therapy and diagnosis of different diseases, especially cancer, which postulates promising
future for nanotechnology in medical applications.
In cancer therapy, radiotherapy remains a major modality of cancer therapy.
Improvements include the use of megavolt (6–25MV) X-rays to avoid skin damage,
tomotherapy and intensity-modulated radiation therapy (IMRT) to better concentrate the
dose within the shape of the tumor, and better dose fractionation schedules.
In clinical practice, electron beams from linear accelerators have increasingly taken
the place of kilovoltage X-ray beams for skin and subcutaneous tumors because they offer
distinct advantages in terms of dose uniformity in the target volume and in minimizing the
dosage to deeper tissues. Although kilovoltage beams could maximize tumor dose
enhancement, it has technical restrictions. The use of kilovoltage X-rays produces
significant dose heterogeneity inside the target tumor.
Recently years, GNPs have been widely used and analyzed in radiation therapy
because of their extremely small size, good biocompatibility, and ease in chemical
modification. The number of reports on GNP radiosensitization has rapidly increased.
The following thesis aims to study “ The Effect of Gold Nanoparticles as a
Radiosensitizer for Electron Beams in Mice Bearing Ehrlich Ascites Carcinoma”.
The thesis consists of nine Chapters, as follows:
Chapter 1: represents the introduction where it includes notes on nanotechnology
and the applications of nanoparticles in biology, nanomedicine,
nanooncology, with special reference to radiotherapy. In addition to
notes on radiosensitizers and the use of gold nanparticles as
radiosensitizers, and the interaction of x- and gamma rays with gold
nanparticles.
Chapter 2: basic consideration that includes two parts; Part A: concerns with the
classification and types of ionizing and non-ionizing radiation, and the
interaction of ionizing radiation with matter, the radiation units and
measurements. In addition to the types of biological damage from
radiation exposure including acute and chronic radiation damage. Part
B, includes nanomaterials and the methods of processing,
characterization with special reference to gold nanoparticles and their
biomedical applications.
Chapter 3: is the aim of the study which is coincide with the title of the thesis.
Chapter (7) Summary
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Chapter 4: This chapter includes the materials and methods. Divided into sectors
concerning preparation and characterization of gold nanoparticles,
experimental animals and their groups, exposure unit of electron beam
irradiation, in addition to the biochemical methods used throughout
the work.
Chapter 5: The results of the work.
During the study period, treatment with gold nanoparticles injected intratumorally
prior to electron beam irradiation did not cause obvious adverse effects on growth because
no statistically significant differences in body weight gain were observed between the gold
nanoparticle-treated mice and control mice. Furthermore, no abnormal clinical signs or
behavior were detected in either the control or treated groups. However, the exposure to
electron beam irradiation subjected the exposed groups of mice to oxidative stress, whose
level was reduced in the groups of mice injected with GNPs prior to irradiation. Also, the
depression in the white blood counts was lesser on injecting the mice with GNPs prior to
irradiation.