The framework of this work was to develop an emulsion-based edible film based on a chitosan nanoparticle matrix with cellulose nanocrystals (CNCs) as a stabilizer and reinforcement filler. The chitosan nanoparticles were synthesized based on ionic cross-linking with sodium tripolyphosphate and glycerol as a plasticizer. The emulsified film was prepared through a combination system of Pickering emulsification and water evaporation. The oil-in-water emulsion was prepared by dispersing beeswax into an aqueous colloidal suspension of chitosan nanoparticles using high-speed homogenizer at room temperature. Various properties were characterized, including surface morphology, stability, water vapor barrier, mechanical properties, compatibility, and thermal behaviour. Experimental results established that CNCs and glycerol improve the homogeneity and stability of the beeswax dispersed droplets in the emulsion system which promotes the water-resistant properties but deteriorates the film strength at the same time. When incorporating 2.5% w/w CNCs, the tensile strength of the composite film reached the maximum value, 74.9 MPa, which was 32.5% higher than that of the pure chitosan film, while the optimum one was at 62.5 MPa, and was obtained by the addition of 25% w/w beeswax. All film characterizations demonstrated that the interaction between CNCs and chitosan molecules improved their physical and thermal properties.

The isolation of crystalline regions from fibers cellulose via the hydrolysis route generally requires corrosive chemicals, high-energy demands, and long reaction times, resulting in high economic costs and environmental impact. From this basis, this work seeks to develop environment-friendly processes for the production of Bacterial Cellulose Nanocrystals (BC-NC). To overcome the aforementioned issues, this study proposes a fast, highly-efficient and eco-friendly method for the isolation of cellulose nanocrystals from Bacterial Cellulose, BC. A two-step processes is considered: (1) partial depolymerization of Bacterial Cellulose (DP-BC) under ultrasonic conditions; (2) extraction of crystalline regions (BC-NC) by treatment with diluted HCl catalyzed by metal chlorides (MnCl₂ and FeCl₃.6H₂O) under microwave irradiation. The effect of ultrasonic time and reactant and catalyst concentrations on the index crystallinity (CrI), chemical structure, thermal properties, and surface morphology of DP-BC and BC-NC were evaluated. The results indicated that the ultrasonic treatment induced depolymerization of BC characterized by an increase of the CrI. The microwave assisted by MnCl₂-catalyzed mild acid hydrolysis enhanced the removal of the amorphous regions, yielding BC-NC. A chemical structure analysis demonstrated that the chemical structures of DP-BC and BC-NC remained unchanged after the ultrasonic treatment and MnCl₂-catalyzed acid hydrolysis process.

Membrane emulsification entails the use of two immiscible liquids for preparation of oil-in-water or water-in-oil emulsions of well-defined droplet size. In this work, we have developed a novel approach for preparation of polymeric nano-objects of various morphologies based on self-assembly of diblock copolymers in tandem with microporous membrane technology (Shirasu porous glass (SPG) membranes). Diblock copolymers poly(oligoethylene glycol acrylate)-b-poly(styrene) (POEGA-b-PSt) comprising different block lengths were prepared by RAFT polymerization. Self-assembly using SPG membrane technology was subsequently conducted by first dissolving the polymer in tetrahydrofuran, followed by continuous passage of this copolymer solution through the membrane pores into the aqueous phase. The results indicate that it is possible to conveniently tune the nano-object morphology via the process parameters of pressure and pore size for a given formulation. The technique also holds promise with regards to high throughput, in particular in the case of vesicles.

SINTESIS NANOPRTIKEL KITOSAN MELALUI TEKNIK EMULSIFIKASI SIMULTAN DAN SELF-ASSEMBLY NANOPARTICLES SEBAGAI MATERIAL KEMASAN AKTIF

Recently, drug nanoparticles formulation using Poly Lactic Acid-Cellulose nanocrystal (PLA-CNC) have been introduced. PLA-CNC were prepared by emulsion method for antidiabetic drug delivery applications. PLA is one of polymer which potentially used as raw material of drug delivery because it has the ability to bind and carry drugs into cell target, but the hydrophilic character of PLA can cause the degradation of PLA in the body run slowly, so it is necessary combining PLA with CNC to improve its property. In this study, special attention has been given to the modification of PLA-CNC as a drug delivery matrix to obtain the optimum drug release of antidiabetic drugs. In this study drug release analysis was conducted at 35-39 °C and pH range 3 to 9 with varied of time dissolution 0 to 180 min. PLA-CNC matrixs were characterized using FTIR and SEM, its drug loading capacity, encapsulation efficiency and in vitro drug release behavior was determined by using UV spectrophotometer. It gave the initial burst release at the first hour at 37 °C pH 3.