Poly(D,L-Lactic Acid) (PDLLA) Biodegradable and Biocompatible Polymer Optical Fiber

Abstract

We demonstrate that commercially available poly(D,L-lactic acid) (PDLLA) is a suitable material for the fabrication of biodegradable optical fibers with a standard heat drawing process. To do so we report on the chemical and optical characterization of the material. We address the influence of the polymer processing on the molecular weight and thermal properties of the polymer following the preparation of the polymer preforms and the fiber optic drawing process. We show that cutback measurements of the first optical fibers drawn from PDLLA return an attenuation coefficient as low as 0.11 dB/cm at 772 nm, which is the lowest loss reported this far for optical fibers drawn from bio-resorbable material. We also report on the dispersion characteristics of PDLLA, and we find that the thermo-optic coefficient is in the range of −10 −4°C−1. Finally, we studied the degradation of PDLLA fibers in vitro, revealing that fibers with the largest diameter of 600 µm degrade faster than those with smaller diameters of 300 and 200 µm and feature more than 84% molecular weight loss over a period of 3 months. The evolution of the optical loss of the fibers as a function of time during immersion in phosphate-buffered saline indicates that these devices are potential candidates for use in photodynamic therapy-like application scenarios.

Agarose-based structured optical fibre

“…It must be stressed that the 3.23 dB/cm loss is still high in comparison to glass 2 and polymer fibres 3,11,12 , and fabrication is also restricted by the mould dimensions, so it is not possible to produce kilometres of fibres like in preform drawing towers. Nevertheless, short fibre segments can be coupled to silica launching and collecting www.nature.com/scientificreports www.nature.com/scientificreports/ fibres to be used in laboratory setups for biochemical sensing and light delivery in which the transmission losses do not critically compromise the system response 16,17 .…”

“…As to polymer devices, a citrate-based fibre with improved optical and mechanical properties was developed and successfully tested on imaging and in vivo analyses 3 . In another work, poly(L-lactic acid)-based fibres obtained through preform drawing were conceived as implantable waveguides, exhibiting low attenuation coefficient and excellent biocompatibility 10,11 . Remarkable results were also achieved by microstructured dual-core fibres made of cellulose butyrate.…”

Optical Waveguides and Integrated Optical Devices for Medical Diagnosis, Health Monitoring and Light Therapies

“…In one study, an unclad PDLLA-based optical fiber manufactured by granulate melting and heat drawing has been demonstrated to take two to three months to degrade in the human body [ 33 ]. Particularly, these fibers have an attenuation coefficient of 0.11 dB/cm at 772 nm, which is the lowest loss reported so far for optical polymer fibers.…”

“…In addition, cases regarding the biocompatibility of PDLLA in vivo have been reported, where no clinical signs of foreign body reactions have been discovered. This type of fibers can be used to deliver light in vivo for light sensing applications [ 33 ]. Another type of comb-shaped slab waveguide (see Figure 3 a) is fabricated by using melt pressing, solvent casting, laser cutting and ultraviolet-induced crosslinking techniques, which can be used for long-term light delivery [ 34 ].…”

Latest Achievements in Polymer Optical Fiber Gratings: Fabrication and Applications

“…Different kinds of plastic material with unique advantages can be used for POF fabrication besides polymethyl methacrylate (PMMA), which is the most common material with a low cost [2]. Examples of these materials are low water absorption cyclic olefin copolymers (TOPAS) [3], high glass transition temperature cyclic-olefin polymer (ZEONEX) [4], excellent clarity and impact strength engineering plastic (Polycarbonate) [5], biodegradable and biocompatible poly(D,L-lactic acid) (PDLLA) [6], and low-loss cyclic transparent amorphous fluoropolymers (CYTOP) [7]. In addition to fiber materials, several types of POFs are available in the current market with different core sizes and structures, such as small-diameter step-index (SI) POF, small-diameter microstructure POF, commercial grade-index (GI) POF, and commercial large-diameter PMMA POF, as shown in Table 1.…”