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

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 l-lactic acid (l-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 l-LA and polyvinyl alcohol, leads to different phase differences, forming l-LA films. A modified microscope system was used to observe the appearance of the l-LA wave plates. Six layers and 0.8% l-LA solution were the optimal conditions to fabricate an l-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 l-LA film. The performance of the l-LA film was consistent with that of a commercial quarter-wave plate. In conclusion, circularly polarized light was successfully produced using the l-LA film. The biodegradable l-LA film has widespread application in the field of biomedicine. Featured Application: l-Lactic acid film uses biodegradable and biocompatible materials. It can produce circularly polarized light and is beneficial for application in biomedicine.