New, complex radiotherapy delivery techniques require dosimeters that are able to measure complex three-dimensional dose distributions accurately and with good spatial resolution. Polymer gel is an emerging new dosimeter being applied to these challenges. The aim of this review is to present a practical overview of polymer gel dosimetry, including gel manufacture, imaging, calibration and appli...

In this paper, we report results obtained from a biosensor comprised of a monolithic silica sol–gel entrapping glucose oxidase (GOD) as sensing element coupled to a fibre-optic transducer element. GOD intrinsic fluorescence spectra were analysed in the UV and visible region in presence of different glucose concentrations, and the corresponding calibration curves were obtained. In addition, time...

A method is described for the separation of the three major classes of human serum lipoproteins by gel filtration on columns of 4 and 6% agarose gel. After calibration of the columns, the elution volumes of the lipoproteins were used to calculate the molecular sizes and molecular weights of these macromolecules. The technique was employed to demonstrate aggregation of low density lipoprotein fo...

Amphoteric azo dyes were used for internal control of pI values in Comparative two-dimensional Fluorescence Gel Electrophoresis (CoFGE) [1]. The 2D-gel images of separated Escherichia coli proteins as well as those of colored amphoteric dyes separated by isoelectric focussing are presented. The latter were used to correct for variation in the first electrophoretic dimension and further improve ...

Background: In this work investigation of the normoxic PAGAT polymer gel dosimeter such as sensitivity, the R2-dose response with post time and the percentage depth dose (PDD) of PAGAT polymer gel dosimeter have been undertaken. Materials and Methods: Using MRI, the formulation to give the maximum change in the transverse relaxation rate R2 was determined to be 4.5% N,N'-methylenbis- ...

There is a need for stable gel materials for phantoms used to validate optical computerized tomography (CT) scanners used in conjunction with radiation-induced polymerizing gel dosimeters. Phantoms based on addition of light-absorbing dyes to gelatine to simulate gel dosimeters have been employed. However, to more accurately simulate polymerizing gels one requires phantoms that employ light-sca...

Some dosimeters require a relationship between detector signal and delivered dose. The relationship (characteristic curve or calibration equation) usually depends on the environment under which the dosimeters are manufactured or stored. To compensate for the difference in radiation response among different batches of dosimeters, the measured dose can be scaled by normalizing the measured dose t...

introduction: polymer gels are modern dosimeters providing three dimensional dose distributions. these dosimeters can be used in brachytherapy in which the tumor dimension is relatively small and the dose gradient is high. in this study, the ability of the magica polymer gel was investigated for assessing the absolute dose values as well as the dose distribution of low dose rate (ldr) ir-192 wi...

The determination of the molecular weight distribution by gel permeation chromatography requires the establishment of a molecular weight calibration and efficient columns in order to minimise chromatogram broadening. The separation process is described in terms of steric exclu— sion, retardation and partial exclusion mechanisms in order to show how the universal calibration method may be influe...

Introduction: According to the literature, optical coherence tomography (OCT) can be used measure radiation absorbed dose. This study was carried out to design a computed tomography system for the calculation of absorbed dose and optimization of dose delivery in radiotherapy using gel dosimeters. Material and Methods: An advanced charge-coupled device based OCT system was developed in laborator...