Evaluation of doses in radiotherapy using solid-state composites based on natural colourless topaz

Area of Science:

• Materials Science
• Radiation Dosimetry
• Solid State Physics

Background:

• Thermoluminescence (TL) is a crucial phenomenon for radiation detection.
• Commercial dosimeters like TLD-100 are widely used but have limitations.
• Developing novel, cost-effective TL dosimeter materials is an ongoing research area.

Purpose of the Study:

• To investigate the thermoluminescent properties of topaz-Teflon and topaz-glass composites.
• To compare these novel composites with the established TLD-100 dosimeter.
• To evaluate the suitability of topaz composites for absorbed dose measurements in radiotherapy.

Main Methods:

• Composites of powdered topaz embedded in Teflon or glass were prepared.
• Thermoluminescent properties (sensitivity, fading, reproducibility, re-usability) were analyzed.
• Absorbed doses were measured using gamma irradiation from a 60Co source (1cGy-2Gy) in simulated radiotherapy setups.

Main Results:

• Topaz composites demonstrated comparable relative sensitivity and TL fading to TLD-100.
• The sample preparation process showed good reproducibility.
• Re-utilization of the topaz dosimeters was feasible.
• Dose profiles obtained in acrylic plates closely mimicked those in equivalent tissues.

Conclusions:

• Natural colourless topaz crystals, when formed into composites, function effectively as TL dosimeters.
• These topaz-based composites offer a viable alternative to commercial dosimeters for radiotherapy applications.
• The study confirms the potential of topaz composites for accurate absorbed dose determination.