Incorporation of the sunscreen agent, octyl methoxycinnamate in a cellulosic fabric grafted with β-cyclodextrin

Michler's Ketone: β-Cyclodextrin Host-Guest Inclusion Complex for Enhancing the Ultraviolet Protection Factor of Poplin Cotton Fabric

Michler's ketone (4,4' bis(N,N-dimethylamino)benzophenone) mk is a potential ultraviolet radiation (UVR) absorber in various materials. In this report, we have tested the UVR filtering ability of mk on cotton fabric. The beta-cyclodextrin (β-CD) inclusion complex of mk enhances ultraviolet protection factor (UPF) drastically. The impact of β-CD on the UVR filtering of mk are demonstrated by investigating the guest (mk:absorbers)-host (β-CD:enhancer) inclusion complex. Spectral and molecular docking analysis of mk:β-CD complex infers the vertical insertion of the guest molecule by positioning -C=O group of mk at the center of the host molecule with the exclusion of the terminal atoms of guest molecule outside the β-CD cavity. Thus, the host; β-CD renders an inflexible fit to the guest:mk. The inflexible fit of mk into the β-CD cavity enhances the UVR dissipation when it is incorporated on the poplin cotton fabric. With UPF =46 mk:β-CD complex is proposed as a potential UVR absorber suitable for manufacturing sun protective textiles. The holding of mk by β-CD enhances the UVR dissipation and hence facilitates the native red-shifted emission and non-radiative relaxation by the formation of twisted intramolecular charge transfer in mk.

The Role of β-Cyclodextrin in the Textile Industry-Review

β-Cyclodextrin (β-CD) is an oligosaccharide composed of seven units of D-(+)-glucopyranose joined by α-1,4 bonds, which is obtained from starch. Its singular trunk conical shape organization, with a well-defined cavity, provides an adequate environment for several types of molecules to be included. Complexation changes the properties of the guest molecules and can increase their stability and bioavailability, protecting against degradation, and reducing their volatility. Thanks to its versatility, biocompatibility, and biodegradability, β-CD is widespread in many research and industrial applications. In this review, we summarize the role of β-CD and its derivatives in the textile industry. First, we present some general physicochemical characteristics, followed by its application in the areas of dyeing, finishing, and wastewater treatment. The review covers the role of β-CD as an auxiliary agent in dyeing, and as a matrix for dye adsorption until chemical modifications are applied as a finishing agent. Finally, new perspectives about its use in textiles, such as in smart materials for microbial control, are presented.

Using ordered mesoporous silica SBA-15 to limit cutaneous penetration and transdermal permeation of organic UV filters

Avobenzone (AVO), oxybenzone (OXY), and octyl methoxycinnamate (OMC), are widely used UV filters. The aim of this study was to investigate the effect of incorporation in mesoporous silica (SBA-15) on their cutaneous deposition and permeation. Stick formulations containing "free" and "incorporated" UV filters (SF1 and SF2, respectively) were prepared and characterized with respect to their physicochemical, thermal, and functional properties. Cutaneous delivery experiments using porcine skin with quantification by UHPLC-MS/MS, demonstrated that skin deposition of AVO and OXY after application of SF2 for 6 and 12 h was significantly lower than that from SF1 at each time-point (Student t-test, p < 0.05): e.g. OXY permeation across the skin was 30-, 12- and 1.5-fold lower after 6, 12 and 24 h, respectively, following application of SF2. Cutaneous biodistribution profiles of AVO and OXY to 800 µm evidenced a significant decrease in the amounts in the viable epidermis and dermis. In contrast, deposition of the more lipophilic OMC was not significantly different (p ˃ 0.05). In vitro photoprotective efficacy results demonstrated that adsorption/entrapment of UV filters enhanced the sun protection factor by 94%. In conclusion, SBA-15, an innovative mesoporous material, increased photoprotection by UV filters while reducing their cutaneous penetration and transdermal permeation.

Inclusion complexes of β-cyclodextrin-dinitrocompounds as UV absorber for ballpoint pen ink

2,4-Dinitrophenol (2,4-DNP), 2,4-dinitroaniline (2,4-DNA), 2,6-dinitroaniline (2,6-DNA) and 2,6-dinitrobenzoic acid (2,6-DNB) has appeared for the UV absorption bands in different wavelength region below 400 nm, a combination of these dinitro aromatic compounds gave the broad absorption spectra within the UV region. The absorption intensities have been increased by preparation of the inclusion complex of dinitro compounds with β-cyclodextrin (β-CD). Prepared inclusion complexes are used to improve the UV protection properties of the ball point pen ink against photo degradation. The formation of solid inclusion complexes was characterized by FT-IR, and (1)H NMR spectroscopy. The UV protecting properties of these inclusion complexes were calculated their sun protection factor (SPF) is also discussed. The stability of the ballpoint pen ink has been confirmed by UV-Visible spectroscopic method.

Cotton fabric finished with β-cyclodextrin: Inclusion ability toward antimicrobial agent

β-Cyclodextrin was grafted onto cotton fabric through crosslinking with butane tetracarboxylic acid in presence of sodium hypophosphite monohydrate as a catalyst. This finished cotton fabric was loaded with the antimicrobial agent octenidine dihydrochloride. β-Cyclodextrin-grafted cotton fabrics, both after loading with octenidine dihydrochloride or before loading (control) were characterized for their antimicrobial activity against two types of bacteria (Gram positive and Gram negative) and two types of fungi, using the Diffusion Disk Method. The antimicrobial cotton fabric was subjected to several washing cycles and the antimicrobial activity was measured after each washing cycle to examine the durability of this antimicrobial finishing against repeated washing. The measurements showed that the finished cotton fabrics retain reasonable deal of their antimicrobial activity, even after 20 washing cycles. This long-lasting antimicrobial activity is attributed to the hosting ability of the cavities present in cyclodextrin moieties, which host the antimicrobial agent molecules and release them gradually.