Medical/biological study (experimental study)

The influence of low power microwave on the properties of DPPC vesicles med./bio.

By: Mady MM, Allam MA

Published in: Phys Med 2012; 28 (1): 48-53

Aim of study (acc. to author)

To study the effect of low power microwaves (950 MHz) on some structural and functional properties of liposomes which represent a good cell membrane model. The main objective was to eliminate the heat effect, as claimed by many authors to be the only effect of microwaves.

Endpoint

structural and functional properties of liposomes

Exposure

- 950 MHz
- RF
- microwaves
- mobile communications
- mobile phone

Exposure	Parameters
Exposure 1: 950 MHz Exposure duration: continuous for 1 and 2 hours	power density: 2.5 mW/cm²

Exposure 1

Main characteristics

Frequency	950 MHz
Type	electromagnetic field
Exposure duration	continuous for 1 and 2 hours

Exposure setup

Exposure source	horn antenna
Setup	microwave generator with a horn antenna used; no further details given

Parameters

Measurand	Value	Type	Method	Mass	Remarks
power density	2.5 mW/cm²	-	-	-	-

Exposed system:

artifical biological membranes in aqueous solutions (phospholipids; dipalmitoylphosphatidycholine (DPPC))

Methods Endpoint/measurement parameters/methodology

structural properties (FTIR spectroscopy) and functional properties of liposomes (membrane solubilization (via a non-ionic detergent; spectrophotometry), flow activation energy measurements (via viscosity; rheometer))

Investigated system:

artifical biological membranes in aqueous solutions (phospholipids; dipalmitoylphosphatidycholine (DPPC))

Time of investigation:

before exposure
after exposure

Main outcome of study (acc. to author)

The amount of detergent needed to completely solubilize the liposomal membrane was increased after microwave exposure of liposomes, indicating an increased membrane resistance to the detergent and hence a change in the natural membrane permeation properties.
The data of the FTIR spectroscopy showed spectral changes in the exposed liposome preparations probably due to water loss and molecular conformational changes.
The flow activation energy measurements showed, that low power microwave exposure induced changes in the liposomes deformability (liposome fluidity was decreased and liposome rigidity was increased).
The authors conclude that low power microwaves of 950 MHz induced structural and functional changes in liposomes.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

not stated/no funding

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