## 2 Starch Modification Processes
### Applications of Modified Starch
#### 2.5.3 Applications of Chemically Modified Starch  
Chemically modified starch shows distinct properties over native starch and has been broadly explored in food packaging, pharmaceutical, water treatment, and agriculture applications [1,114]. Table 5 shows the different types of applications in chemical modification processes. Chemically modified starch is mainly used in the food packaging industry due to its film-forming ability. For example, [PERSON] et al. [115] conducted a study to explore the stability of mechanical and chemical properties of thermoplastic starch (TPS) by dual crosslinking using epichlorohydrin. This work indicated the potential of crosslinked TPS for packaging applications. The research carried out by [PERSON] et al. [116] showed the improved tensile strength of crosslinked fava bean starch thin films. In addition, the crosslinked starch films exhibited lower moisture content, water solubility, and water vapour permeability. [PERSON] and coworkers prepared PVA (polyvinyl alcohol)/starch and cellulosic material barley husk (BH)-based composite films using the grafting technique. Authors reported the use of composite films in biodegradable packaging films to replace synthetic non-degradable polymers [117]. Moreover, [PERSON] et al. [118] prepared biodegradable active films using oxidized corn starch. In this study, starch oxidation was performed using sodium periodate, and the films showed enhanced tensile strength and oxygen and water vapour barrier capacities and reduced migration to acid media. [PERSON] et al. [119] prepared packaging materials that possessed high mechanical strength, low water vapor permeability (WVP), antioxidant properties, and biodegradability. In addition, the food compatibility test showed that the migration rates of films were below the overall migration limit. Bio-based adhesives have gained much attention due to health and environmental concerns caused by petroleum-based adhesives. For example, [PERSON] et al. [120] and [PERSON] et al. [121] prepared bio-adhesives using chemically modified starch. Recently, [PERSON] et al. [120] investigated the bio-based adhesives using cassava starch, citric acid, and polycarboxylic acid. [PERSON] et al. [121] prepared the bio-based adhesive using corn starch-g-poly (vinyl acetate-_co_-butyl acrylate). This study showed an increase in thermal stability. Furthermore, [PERSON] et al. [122] developed the grafted starch-based wood adhesive using polyvinyl alcohol and sodium dodecyl sulfate. Chemically modified starch has also been applied in pharmaceutical industries as biodegradable coatings and drug delivery systems. Hydrophilic and hydrophobic carboxymethyl starch derivatives were used to develop drug delivery systems, specifically micro-particles, nanoparticles, and hydrogels, by [PERSON] et al. [123]. [PERSON] and [PERSON] [124] prepared carboxymethyl starch (CMS) microparticles from rice starch with a low amylose content of (6%). They reported that CMS followed an ideal Zero-order kinetics, favorable for a drug delivery system showing the ability of microparticles-based CMS in control drug release at a specific site of the gastrointestinal tract. [PERSON] and coworkers reported the potential of chemically modified waxy corn as emulsifying and stabilizing agents in pharmaceutical applications [125]. Apart from that, [PERSON] et al. [126] prepared the microcapsules using acid hydrolyzed and carboxymethyl corn starch. The authors reported the use of microcapsules for controlled drug delivery. Chemically modified starch has also been considered in the agriculture industry as a fertilizer. For example, [PERSON] et al. [127] prepared the controlled-release nitrogen fertilizer using crosslinked corn starch with improved stability and mechanical strength. [PERSON] et al. [128] prepared cassava starch-graft-polyacrylamideonitrile-coated urea fertilizer, and the results exhibited the N release in the range of 69.8-78.3%. Apart from the fertilizers, modified starch was used in the preparation of agricultural mulch films. [PERSON] et al.