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■Bio-mathematics, Statistics and Nano-Technologies: Mosquito Control Strategies

14.1

INTRODUCTION

Chemical treatments are extensively used in textile finishing procedures to improve

different properties of natural and synthetic fibers. A survey of the updated literature

(Schindler W.D.; Hauser P.J. 2004) reveals that several chemicals are commonly used as

finishes but, due to the intense pressure to ban harmful molecules, various attempts have

been made to replace environmentally hazardous products and to use new procedures in the

preparation of functional coatings for medical applications (Puoci et al. 2020), which allow

combining the entrapment of bioactive compounds with their controlled release. Among

the different methods proposed, the sol-gel process has demonstrated its exceptional poten-

tial with respect to the synthesis of new coatings with a high degree of homogeneity at the

molecular level and exceptional physicochemical properties (Mahltig et al. 2005) and the

application on clothes of derivatives from the plant world, which can be used both as insec-

ticides, to kill insects, and as repellents to keep them away from the human body (Tseghai

2016), can provide an additional layer of protection to the skin, especially in tropical areas.

Protective textiles are among the innovative applications of smart technology and refer

to those textiles that provide protection from something, such as antibacterial, UV protec-

tion, fire protection (flame retardant textiles), self-cleaning, hydrophobicity, or multifunc-

tional materials, all of which are developed with the application of functional finishes to

textile fabrics and can be prepared by sol-gel assisted immobilization of bioactive agents,

biomolecules and biopolymers. High economic growth rates are expected in the world mar-

ket of technical textiles (Haufe et al. 2008) because sol–gel nanocomposite hybrids have

been shown to enable the chemical modification of natural fibres and produce a solid-state

material from a chemically homogeneous precursor onto the textile substrate. By trapping

the “randomness of the state of the solution” and thus ensuring the atomic mixing of the

reagents, you should be able to produce complex inorganic materials such as ternary and

quaternary oxides at lower processing temperatures and shorter synthesis times.

For the immobilization of biomolecules, the sol-gel technique provides mild process-

ing conditions (physiological, pH and temperature) and single-step processing, employing

conventional machinery used in industrial textile finishing, such as pad application or ex-

haust processes, to impart multifunctional properties to the finished fabrics, thus allowing

variations in the composition and structure of the matrix, while keeping the immobilized

biomolecules stable over time. Besides, it is possible to easily make large films during pro-

cessing because the sol-gel method is a liquid phase process (Li et al. 2007), to control

over morphology and particle size (Kakihana 1996) and to ensure excellent adhesion on

cotton, attained through condensation between the –OH groups of the hydrolyzed silanes

and those present on the surface of cellulose.

As already demonstrated (Ardanuy et al. 2014), the resulting silica-based layers can

act as a matrix for embedding additives or active ingredients homogeneously into fabrics,

leading to novel textile finishing, with controlled delivery properties (Haufe et al. 2008),

thus presenting an alternative to toxic carriers. Accordingly, silica precursors should be in-