Teqs multimode fo

All the reagents used in this work were of analytical grade (99.99% purity, unless otherwise specified). Ultra-clean deionized water (DIW), purified by a TKA Milli-Q 50 system, was consistently used throughout the experiments. Acetone, sulfuric acid (97% H₂SO₄), D( +)-sucrose, ethanol and aniline (99% C₆H₅NH₂) were supplied by Merk. The nitrogen and oxygen 5.0 purity gas bottles were acquired from Messer. The TEQS multimode FO of 400 μm diameter was provided by Thorlabs. The additional tools used in the aniline polymerization protocol, such as the Pasteur glass pipettes (2 mL capacity, 230 mm length), the double-wall glass (diameter 55 mm, capacity 150 mL, height 85 mm) and the magnetic stir plate were obtained from VWR. The TC120 heated circulating bath was purchased from Grant Instruments.

All the reagents used in this work were of high purity and suitable for analytical applications. During the experiments, ultra-pure deionized water (DIW), purified by the TKA Mili-Q 50 system, was regularly employed. In order to fabricate the optical fiber (FO) sensors, a TEQS multimode FO of 400 $\mathsf{\mu }$ m diameter was acquired from Thorlabs. Acetone, aniline (C ${}_6$ H ${}_5$ NH ${}_2$ ), ammonium persulfate ((NH ${}_4$ ) ${}_2$ S ${}_2$ O ${}_8$ ), toluene, hydrochloric acid (HCl), chitosan, bovine serum albumin (BSA), phosphate-buffered saline (PBS), acetic acid (CH ${}_3$ COOH), zinc chloride (ZnCl ${}_2$ ), cobalt chloride (CoCl ${}_2$ ), and cadmium iodide (CdI ${}_2$ ) were supplied by Merck.