Bioactive Carboxymethyl Cellulose (CMC)-Based Films Modified with Melanin and Silver Nanoparticles (AgNPs)—The Effect of the Degree of CMC Substitution on the In Situ Synthesis of AgNPs and Films’ Functional Properties

Abstract

Green synthesis of nanoparticles for use in food packaging or biomedical applications is attracting increasing interest. In this study, the effect of the degree of substitution (0.7, 0.9 and 1.2) of a carboxymethylcellulose polymer matrix on the synthesis and properties of silver nanoparticles using melanin as a reductant was investigated. For this purpose, the mechanical, UV–Vis barrier, crystallinity, morphology, antioxidant and antimicrobial properties of the films were determined, as well as the color and changes in chemical bonds. The degree of substitution effected noticeable changes in the color of the films (the L* parameter was 2.87 ± 0.76, 5.59 ± 1.30 and 13.45 ± 1.11 for CMC 0.7 + Ag, CMC 0.9 + Ag and CMC 1.2 + Ag samples, respectively), the UV–Vis barrier properties (the transmittance at 280 nm was 4.51 ± 0.58, 7.65 ± 0.84 and 7.98 ± 0.75 for CMC 0.7 + Ag, CMC 0.9 + Ag and CMC 1.2 + Ag, respectively) or the antimicrobial properties of the films (the higher the degree of substitution, the better the antimicrobial properties of the silver nanoparticle-modified films). The differences in the properties of films with silver nanoparticles synthesized in situ might be linked to the increasing dispersion of silver nanoparticles as the degree of CMC substitution increases. Potentially, such films could be used in food packaging or biomedical applications.

The Antimicrobial Activity of Melanin-Mediated Synthesis of Silver Nanoparticles

“…A maximum zone of inhibition was recorded for S. aureus (22mm), as mentioned by Gurme et al (31) . As mentioned by Macieja et al (32) melanin act as a metal salt reducer and further stabilizes the nanoparticles (acting as a capping agent ), and their antimicrobial activity is largely due to the induction of pores in cell membranes, which is attributed to the interaction of silver with sulfurcontaining membrane proteins.…”

“…Sterile cotton swabs were used to transfer and spread the test microorganism onto the agar medium, and then 5 wells were made into the agar using a sterile egel puncture with a diameter of 4 mm. After that, various concentrations (8,16,32,64,128,256, 512 and 1024 µg/ml) of AgNPs, extract melanin, and a combination of both were added to the wells and then incubated for 24 hrs at 37 °C. AgNPs were dissolved by an ultrasonic cleaner device in deionized sterile water.…”

Influence of Carboxymethyl Cellulose on the Green Synthesis of Gold Nanoparticles Using Gliricidia sepium and Petiveria alliacea Extracts: Surface-Enhanced Raman Scattering Effect Evaluation

“…Natural derivatives such as chitosan, hydroxypropylmethylcellulose, and other cellulose derivatives such as ethylcellulose , and carboxymethylcellulose , have also been used. The latter is mentioned as a reducing agent and stabilizer of MNPs , and as a matrix to form metallic films for biomedical applications. , Carboxymethyl cellulose or CMC is a linear-chain macromolecular polymer based on covalent bonds of d -glucopyranoses , due to its hydrosolubility and biocompatibility properties. This research focuses on the use of CMC as a stabilizing and supporting agent for AuNPs and its use for pyridoxine (Pd) (vitamin B6) detection by surface-enhanced Raman scattering (SERS); it also highlights the biocompatibility of the SERS analysis with the green synthesis of MNPs, stimulating the promotion of additional biocompatible mechanisms integrated with this synthesis methodology for the conservation and applicability of colloidal nanoparticles …”

“…Natural derivatives such as chitosan, 22 hydroxypropylmethylcellulose, 23 and other cellulose derivatives such as ethylcellulose 24 , 25 and carboxymethylcellulose 26 , 27 have also been used. The latter is mentioned as a reducing agent and stabilizer of MNPs 26 , 27 and as a matrix to form metallic films 28 for biomedical applications. 29 , 30 Carboxymethyl cellulose or CMC is a linear-chain macromolecular polymer based on covalent bonds of d -glucopyranoses 24 , 31 due to its hydrosolubility and biocompatibility properties.…”

Effect of Melanin on the Stability of Casein Films Exposed to Artificially Accelerated UV Aging

“…Among other things, they influence the improvement of mechanical properties (due to the strong hydrogen interactions of melanin with the polymer matrix), antioxidant, antimicrobial and UV-protective properties [22]. They have been used to improve the performance of films based on such polymer matrices as agar [23], chitosan [24], polyhydroxy butyrate (PHB) [25], carboxymethyl cellulose (CMC) [26,27], alginate [28], gelatin [29], whey protein concentrate/isolate [30], and carrageenan [31], among others.…”