Diaminated Starch: A Competitor of Chitosan with Highly Mucoadhesive Properties due to Increased Local Cationic Charge Density

Abstract

The purpose of this study was to synthesize diaminated starch as a novel mucoadhesive polymer. Starch was tosylated and then reacted with ethylenediamine. The degree of amination was determined by 2,4,6-trinitrobenzene sulfonic acid assay. Properties of diaminated starch including solubility, cytotoxicity, swelling behavior, and mucoadhesion were compared to chitosan. Diaminated starch displayed 2083 ± 121.6 μmol of diamine substructures/g of polymer. At pH 6, diaminated starch exhibited a ζ potential of 6 mV, whereas it was close to zero in the case of unmodified starch. In addition, diaminated starch displayed water solubility over the entire pH range and minor cytotoxicity. The novel polymer showed pronounced swelling behavior in water increasing its initial weight 18-and 6-fold at pH 5 and 6, respectively. Moreover, diaminated starch exhibited 92-fold higher-mucoadhesivity properties than those of chitosan. According to these results, diaminated starch might be a promising novel excipient for the design of mucoadhesive formulations.

Long-Term Vaccine Delivery and Immunological Responses Using Biodegradable Polymer-Based Carriers

“…Many attempts have been accomplished to make different chitosan derivatives such as quaternized chitosan, thiolated chitosan, carboxymethyl chitosan, and hydroxypropyl chitosan with better properties in adhesion, biocompatibility, and solubility. The importance of the amine group in chitosan led to attempts to make aminated polysaccharides based on cellulose and starch . Among the chitosan derivatives used in vaccine delivery, quaternary chitosan has been able to act as an adjuvant vaccine to activate antigen-presenting cells due to its unique biological and physicochemical properties …”

“…The importance of the amine group in chitosan led to attempts to make aminated polysaccharides based on cellulose and starch. 18 Among the chitosan derivatives used in vaccine delivery, quaternary chitosan has been able to act as an adjuvant vaccine to activate antigen-presenting cells due to its unique biological and physicochemical properties. 19 Cellulose is the most abundant natural polymer and is mainly found as the main substance in plant cell walls.…”

Mucoadhesive Nanoformulations and Their Potential for Combating COVID-19

“…The recently developed diaminated cationic starch presented a tenfold increase in mucoadhesive potency compared with chitosan due to the protonation of both -NH 2 and -NH- groups of the former at acidic pH, compared with the protonation of only -NH 2 group of chitosan at the same pH. Monoaminated cationic cellulose and starch present substantial mucoadhesive profiles at pH below 6.5 [ 14 ]. Notably, the cationic nature of the polysaccharide enables electrostatic interactions with the sialic acid component of mucus, hence offering mucoadhesive characteristics.…”

Starch-Based Composite Films with Enhanced Hydrophobicity, Thermal Stability, and UV-Shielding Efficacy Induced by Lignin Nanoparticles

“…Starch is a widely available and low-cost biodegradable polymer. , Due to the brittleness and non-film-forming ability, polyvinyl alcohol (PVA) and polyethylene oxide (PEO) are commonly used to blend with starch to prepare a starch-based composite film for the potential application. − However, the hydrophilicity of starch greatly limits its application performance, such as being used as the competitive commercial packaging material. The abundant intrinsic hydroxyl groups can adsorb much water, especially in the moist environment, which would weaken the corresponding strength and even break the starch film . To enhance the hydrophobicity, many approaches have been attempted, especially for the chemical modification, which usually involves the use of many reagents and are environmentally unfriendly.…”

“…The abundant intrinsic hydroxyl groups can adsorb much water, especially in the moist environment, which would weaken the corresponding strength and even break the starch film. 32 To enhance the hydrophobicity, many approaches have been attempted, especially for the chemical modification, which usually involves the use of many reagents and are environmentally unfriendly.…”