Fabrication of biodegradable films using <sc>l</sc>-lactate as a chiral material to produce circularly polarized light

Abstract

&lt;abstract&gt; &lt;p&gt;Optical activity and its relation to molecular chirality are significant in the measurement of optical rotation or circular dichroism characteristics to determine the absolute configuration of a chiral molecule. A quarter-wave plate, which is usually made from quartz, can convert linearly polarized light into circularly polarized light. In this study, we suggest using &lt;sc&gt;l&lt;/sc&gt;-lactic acid (&lt;sc&gt;l&lt;/sc&gt;-LA), a chiral material, and a water-based transparent glue to produce biodegradable films. Adjusting the number of thin layers, which are deposited from the mixture of &lt;sc&gt;l&lt;/sc&gt;-LA and polyvinyl alcohol, leads to different phase differences, forming &lt;sc&gt;l&lt;/sc&gt;-LA films. A modified microscope system was used to observe the appearance of the &lt;sc&gt;l&lt;/sc&gt;-LA wave plates. Six layers and 0.8% &lt;sc&gt;l&lt;/sc&gt;-LA solution were the optimal conditions to fabricate an &lt;sc&gt;l&lt;/sc&gt;-LA film. The circular polarization experiment showed that the changes in maximum and minimum light intensity were within 2% compared to the average light intensity at a specific angle of the &lt;sc&gt;l&lt;/sc&gt;-LA film. The performance of the &lt;sc&gt;l&lt;/sc&gt;-LA film was consistent with that of a commercial quarter-wave plate. In conclusion, circularly polarized light was successfully produced using the &lt;sc&gt;l&lt;/sc&gt;-LA film. The biodegradable &lt;sc&gt;l&lt;/sc&gt;-LA film has widespread application in the field of biomedicine. Featured Application: &lt;sc&gt;l&lt;/sc&gt;-Lactic acid film uses biodegradable and biocompatible materials. It can produce circularly polarized light and is beneficial for application in biomedicine.&lt;/p&gt; &lt;/abstract&gt;