UV Protection Research Articles

Novel pyrimidine-anthraquinone dyes: Design, synthesis, textile applications & their computational SAR analysis

The integration of functional textiles production approach, correlated with organic synthesis and computational elaboration of synthesized anthraquinone-based pyrimidine dyes, makes a significant contribution in multidisciplinary research. The central focus of this project is the production of multipurpose chemical moieties, addressing the current imperative to reduce the human consumption and mitigate the depletion of natural resources by employing cost-effective methods. The present study is focused to synthesize some new molecules as dyes having antibacterial and UV-protection ability. These synthesized dyes were characterized by UV, FT-IR, 1H NMR, 13C NMR spectroscopic analysis that confirmed the structures of targeted molecules. These targeted dyes were applied to fabric and their colorfastness properties were checked according to ISO recommended procedures. The fastness results supported efficient fixation and fading resistance. The Ultraviolet Protection Factor (UPF) studies were conducted to measure the UV-protection ability of the dyed fabric. Furthermore, antibacterial ability of dyes was also checked, and experimental results were compared through molecular docking study. Dyes were screened for their absorbance under solvents of different polarity, and these were further analyzed by TD-DFT and DFT analysis.

Development of multifunctional zein-based films engineered with gallic acid and Ag NPs loaded γ-CD-MOFs for pork preservation

The increasing emphasis on food quality and consumer safety has prompted researchers to explore green manufacturing techniques for packaging materials. In this study, γ-cyclodextrin metal-organic frameworks (γ-CD-MOFs) were prepared as promising nanocarriers for gallic acid (GA) and silver nanoparticles (Ag NPs). These nanocarriers (GA-Ag@CD-MOFs) were further incorporated into a zein matrix to fabricate multifunctional composite films, referred to as MOFs-Zein. Scanning electron microscopy (SEM) and atomic force microscope (AFM) analysis indicated that the fabricated composite film exhibited excellent biocompatibility, with GA-Ag@CD-MOFs uniformly dispersed within the film matrix. Fourier transform infrared spectroscopy (FT-IR) result revealed that the incorporation of GA-Ag@CD-MOFs facilitated the formation of intermolecular hydrogen bonds with the matrix polymer. The addition of GA-Ag@CD-MOFs enhanced the tensile strength of the composite film by 19.70 %, improved the water barrier performance by 57.76 %, and provided almost 100 % UV protection. The exceptional controlled release capability of γ-CD-MOFs for GA empowered the composite films to maintain their robust initial antioxidant capacity even after 100 days of storage. Moreover, the composite films performed high-efficiency antibacterial activity against Escherichia coli O157:H7 and Salmonella enterica. Acute toxicological studies showed no histopathology related toxicity was found in GA-Ag@CD-MOFs treated mice. When applied to fresh pork, the composite films significantly reduced the key quality indicators of raw meat, compared to the control film. Overall, this work presents a promising approach to fabricate the composite films as a sustainable and functional solution for green functional food packaging.

Preparation and properties of sustainable superhydrophobic cotton fabrics modified with lignin nanoparticles, tannic acid and methyltrimethoxysilane

Functional superhydrophobic cotton fabrics find extensive applications in both textile and non-textile domains. Nonetheless, fabric treatment typically relies on fluorine-containing compounds, inorganic nanoparticles and potentially hazardous organic solvents, posing environmental risks during fabrication and disposal. To address this issue, endeavours are underway to develop environmentally sustainable and cost-effective methods and materials for imparting superhydrophobic properties to cotton fabric surfaces. Here, we prepared lignin nanoparticles (LNP) utilising deep eutectic solvents and facilitated their surface adhesion to cotton fabrics through the self-polymerisation of tannic acid (TA) under alkaline conditions for the construction of micro-/nanostructures on the fabric surface. Subsequently, methyltrimethoxysilane (MTMS) was employed to confer superhydrophobic properties to the fabrics using a combination of thermal chemical vapour deposition techniques, resulting in a contact angle of approximately 164.3° and a sliding angle of 8.52°. Owing to the combined effect of TA and LNP, the modified fabrics exhibited excellent ultraviolet (UV) shielding ability (UV transmittance < 1 %, UV protection factor = 50 + ) and photothermal conversion (54.2 °C in 150 s). In short, micro-/nanostructures with surface hydrophilicity were constructed on the surface of cotton fabrics using two hydrophilic biomaterials, i.e. TA, which is similar to polydopamine but lighter in colour and less expensive, and LNP as sustainable colloidal particles. Subsequently, their surface roughness was further enhanced, and superhydrophobic properties were imparted through modification with the low surface energy substance MTMS. This method not only promotes the high-value utilisation of lignin but also serves as a reference for constructing superhydrophobic structures using biomass hydrophilic materials on cellulose substrates. The prepared superhydrophobic fabric suggests potential applications in water and stain repellence, self-cleaning, outdoor UV protection and the management of marine oil spill pollution.

Molecular Engineering for UV-Vis to NIR Absorption/Emission Bands of Pyrazine-based A-π-D- π-A Switches to Design TiO2 Tuned Dyes: DFT Insights.

This study investigates the tuning of the UV-Vis/NIR absorption bands of pyrazine-based A-D-A switches for designing efficient UV retardancy over TiO2 surfaces. The electronic properties and optical characteristics of seven dyes (DP1-DP7) were analyzed using computational methods. The results indicate that the dyes possessed distinct UV-Vis/NIR absorption properties. Their absorption wavelengths ranged from 389 to 477nm, with corresponding energies ranging from 2.59 to 3.19eV. The major contributions to the absorption were found to be the HOMO-LUMO transitions, varying from 86 to 96%. The dyes exhibited different donor (D) and acceptor (A) groups, influencing their electronic properties and absorption characteristics. The tunable electronic and optical properties of these dyes make them promising candidates for applications requiring UV protection for TiO2-based materials. The results contribute to understand the structure-property relationships in the design of UV-Vis/NIR absorbers and provide a foundation for further experimental investigations in the field of UV retardancy.

Fabrication and Application of Tannin Double Quaternary Ammonium Salt/Polyvinyl Alcohol as Efficient Sterilization and Preservation Material for Food Packaging.

Food packaging films play a vital role in preserving and protecting food. The focus has gradually shifted to safety and sustainability in the preparation of functional food packaging materials. In this study, a bisquaternary ammonium salt of tannic acid (BQTA) was synthesized, and the bioplastics based on BQTA and polyvinyl alcohol (PVA) were created for packaging applications. The impact of BQTA on antibacterial effect, antioxidant capacity, opacity, ultraviolet (UV) protective activity, mechanical strength, thermal stability, and anti-fog of the resultant bioplastics was examined. In vitro antibacterial experiments confirmed that BQTA possesses excellent antimicrobial properties, and only a trace amount addition of BQTA in PVA composite film could inhibit about 100% of Escherichia coli and Staphylococcus aureus. Compared to BQTA/PVA bioplastics with pure PVA, the experiment findings demonstrate that BQTA/PVA bioplastics show strong antioxidant and UV protection action and the performance of fruit preservation. It also revealed a small improvement in thermal stability and tensile strength. The small water contact angle, even at low BQTA concentrations, gave BQTA/PVA bioplastics good anti-fog performance. Based on the findings, bioplastics of BQTA/PVA have the potential to be used to create packaging, and they can be applied as the second (inner) layer of the primary packaging to protect food freshness and nutrition due to their antioxidant activity and biocompatibility.

The National Cancer Aid monitoring (NCAM-online) of ultraviolet radiation risk and protection behavior: a population-based observational trend study with four annual online survey waves

BackgroundUltraviolet (UV) radiation is the most important risk factor for skin cancer development. Sunlight is the main source of UV radiation in the general population. In addition, tanning beds are a source of artificial UV radiation. Since the incidence of skin cancer is increasing worldwide, it is necessary to monitor UV-related risk behaviors such as intentional indoor and outdoor tanning, as well as sun protection behavior in the general population and specific subgroups and settings. This is the aim of the National Cancer Aid Monitoring online (NCAM-online), a continuation and further development of the NCAM.MethodsThe NCAM-online is a longitudinal trend study consisting of four annual survey waves. Each year, 4,000 individuals aged 16–65 years living in Germany will be surveyed using online questionnaires. Each year, intentional indoor and outdoor tanning will be assessed. In addition, varying specific topics regarding skin cancer prevention, such as the utilization of skin cancer screening, will be addressed in the questionnaires.DiscussionThe findings of the NCAM-online will provide an important basis for the German Cancer Aid and Working Group on Dermatologic Prevention (Arbeitsgemeinschaft Dermatologische Prävention, ADP) to develop targeted prevention campaigns and projects aimed at preventing skin cancer. The explorative nature of the NCAM-online allows for the identification of new potential starting points for prevention and education. In addition, the longitudinal design allows for a description of the trend in the prevalence of intentional tanning. For tanning bed use, representative trend data from 2012 are available for Germany, to which NCAM-online will add annual data until 2027.

Melanoma Incidence and Mortality Trends in Sweden.

Over the past decades, many global regions have experienced a steady increase in the incidence of cutaneous melanoma. However, more recently, a downward trend has been observed in the younger age groups in Australia and the US. Yet, in Europe, none of the countries have reported any significant decline in melanoma incidence for any age group. To assess melanoma incidence and mortality trends in Sweden, with a focus on individuals younger than the average age of melanoma onset. This cohort study used data on the national population from the Swedish Melanoma Registry and the Swedish Cancer Registry, which cover more than 99% of all primary invasive cutaneous melanomas diagnosed in the country. All patients diagnosed from 1990 to 2022 were included. Incidence and mortality rates per 100 000 inhabitants were calculated for each year and shown as average annual rates for every 5-year period from 1990 to 2022. Joinpoint regression models were used to evaluate statistical significance of temporal trends and points of change. There were 34 800 primary invasive cutaneous melanomas (19 582 [56.3%] in females and 15 218 [43.7%] in males) reported in 33 324 individuals younger than 60 years (median [IQR] age, 48 [36-58] years) from 1990 to 2022. A consistent rise in melanoma incidence was observed among those 50 to 59 years old. The age groups from 20 to 29 years, 30 to 39 years, and 40 to 49 years showed an incidence peak in 2013 to 2015 followed by stable or significantly declining rates until 2022. In patients younger than 20 years, melanoma incidence remained low with no significant trends. There was also a significant decline in melanoma mortality among 30- to 59-year-old individuals, but not in those 60 years and older. The findings of this cohort study showed a significant recent downward trend in both melanoma incidence and melanoma mortality in the age group 30 to 49 years in Sweden. The reasons for these declines are unclear but may include UV protection, public health campaigns, changing population demographics, and the introduction of effective melanoma treatment. None of these possibilities were evaluated; further study is needed.

Photon shifting and trapping in perovskite solar cells for improved efficiency and stability

Advanced light management techniques can enhance the sunlight absorption of perovskite solar cells (PSCs). When located at the front, they may act as a UV barrier, which is paramount for protecting the perovskite layer against UV-enabled degradation. Although it was recently shown that photonic structures such as Escher-like patterns could approach the theoretical Lambertian-limit of light trapping, it remains challenging to also implement UV protection properties for these diffractive structures while maintaining broadband absorption gains. Here, we propose a checkerboard (CB) tile pattern with designated UV photon conversion capability. Through a combined optical and electrical modeling approach, this photonic structure can increase photocurrent and power conversion efficiency in ultrathin PSCs by 25.9% and 28.2%, respectively. We further introduce a luminescent down-shifting encapsulant that converts the UV irradiation into Visible photons matching the solar cell absorption spectrum. To this end, experimentally obtained absorption and emission profiles of state-of-the-art down-shifting materials (i.e., lanthanide-based organic-inorganic hybrids) are used to predict potential gains from harnessing the UV energy. We demonstrate that at least 94% of the impinging UV radiation can be effectively converted into the Visible spectral range. Photonic protection from high-energy photons contributes to the market deployment of perovskite solar cell technology, and may become crucial for Space applications under AM0 illumination. By combining light trapping with luminescent downshifting layers, this work unravels a potential photonic solution to overcome UV degradation in PSCs while circumventing optical losses in ultrathin cells, thus improving both performance and stability.

First principles study of BN triphenylene-graphdiyne monolayer and bilayer structures with varying C-chain lengths: insights into optical behavior

First-principles calculations engaging density functional theory (DFT) are employed to systematically study the optical characteristics of monolayer and bilayer boron nitride (BN) triphenylene-graphdiyne (Tp-BNyne) structures featuring varying lengths of C-chains. The thermal stability of Tp-BNyne structures at temperatures up to 1000 K is verified. The weak van der Waals interactions due to the small binding energies and significant interlayer distances maintain the cohesion between the layers. The investigation revealed that all Tp-BNyne structures under examination exhibit semiconductor behavior with a band gap in the range of 0.97–2.74 eV. The bilayer configurations demonstrated a narrower energy band gap in comparison to the monolayer ones. Increasing the length of C-chains leads to a reduction in the energy band gap. Delving into the optical behavior of Tp-BNyne structures under photon incidence with parallel and perpendicular polarizations, a distinct anisotropy in the optical characteristics of Tp-BNyne is revealed. The static dielectric constant increases and the optical band gap decreases with increasing C-chain length. The absorption coefficients of monolayer and bilayer Tp-BNyne structures, on the order of 107/m, demonstrate that these sheets can effectively absorb light in the visible and ultraviolet regions. These findings present Tp-BNyne sheets as promising candidates for use in photovoltaic devices to convert sunlight into electrical current, as well as for designing optical devices for ultraviolet protection. Additionally, Tp-BNyne structures are transparent materials, especially in the high-energy range.

Study of ultra-wide bandgap beryllium based perovskite ZBeF3 (Z = Na, Rb, Cs) alloys for smart window applications: A DFT insights

UV radiation affects the human body due to the fact that it might penetrate through the skin and damage biological cells. In the present study, density functional theory (DFT) within the Perdew-Burke-Ernzerhof (PBE) approximations (GGA-PBE) is used to examine certain structural, optical, electronic, and physical characteristics exhibited by the beryllium-based cubic perovskite ZBeF3 (Z = Na, Rb, Cs) compounds. The substances ZBeF3 (Z = Cs, Na, Rb) exhibit space group 221-pm3m, with (4.07, 3.61, and 3.89) Å lattice factors and (67.76, 47.33, and 58.88) Å3 volumes that correspond to their structural features. Simulated findings show that the ZBeF3 (Z = Cs, Na, Rb) exhibit indirect bandgaps of 5.19, 6.12, and 6.61 eV, respectively. All compounds appear to be insulators based on their band structure features. Optical characteristics of compounds such as conductivity, absorption, and reflectivity that represent the interaction between light and matter are investigated. These materials appeared to be robust but brittle, as demonstrated by their greater bulk modulus B with respect to elastic properties, Pugh's ratio, and B/G ratios, in addition to Vickers hardness. According to research, the compound ZBeF3 can be applied to cars, sunglasses, and room windows to serve as UV protection and a reflecting layer.

Fully biobased approach for sustainable flame retardancy, antibacterial and anti-UV modification of silk fabric

The versatile modification of silk fabric using a fully biobased approach is intriguing. In this study, phytic acid and vanillin, which are plant extracts, were utilized to synthesize reactive vanillin phytate ester for modifying silk fabric to achieve durable flame retardancy, antibacterial and anti-UV performance. The multifunctional properties, thermal resistance, smoke and heat suppression capacity, flame-retardant durability and mechanism of modified silk fabrics were investigated. The vanillin phytate ester imparted high antimicrobial and UV resistance to silk fabric, achieving a 97 % inhibition rate against Escherichia coli and reaching an “excellent” level of UV protection. The modified silk fabric also possessed the self-extinguishing capacity, with a limiting oxygen index value as high as 33.5 %. There was also a significant reduction of 71.7 % in peak heat release and 40 % in smoke release compared with those of the original silk. After undergoing 20 washing cycles, the modified silk fabrics also self-extinguished and passed the vertical burning test, and such good washing resistance was achieved by the Schiff base cross-linking of vanillin phytate ester on the silk fabric. An intumescent flame-retardant mechanism was also identified by char residue analyses, which was driven by the synergistic charring action of phosphate groups and aromatic structures.

A review on nanotechnological aspects in medicinal textile

&lt;p&gt;&lt;span lang="EN-US" style="font-size: 10.0pt; line-height: 115%; font-family: 'Times New Roman',serif; mso-fareast-font-family: Calibri; color: windowtext; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;"&gt;Nanoscience and Technology has become popular and touched almost every branch of science and technology. Textile engineering is also not exception. Various nanoparticles are being used in smart textiles and technical textile products. Medical textile is an important area and have much opportunities for innovation and discoveries. Therefore, nanomaterials are used in medical textiles to have exotic properties. Herein we have discussed several methods for the characterization of materials at nanoscale. The common spectroscopic techniques like UV-Visible spectroscopy and microscopic techniques like scanning electron microscopy and transmission electron microscope routinely used in material characterization are discussed in detail. In the last section of the article we discussed various applications of nanomaterials in modern medical textile. The nanomaterials are used in surgical gowns, sanitary napkins, UV protection appliances, antimicrobial coating, sutures etc. Some advanced nanomaterials can be used in disease diagnosis, flame retardants, efficient drug delivery systems etc.&lt;/span&gt;&lt;/p&gt;

Ball-Milling Enhanced UV Protection Performance of Ca2Fe-Sulisobenzone Layered Double Hydroxide Organic Clay.

Using a co-precipitation technique, the anionic form of sulisobenzone (benzophenone-4) sunscreen ingredient was incorporated into the interlayer space of CaFe-hydrocalumite for the first time. Using detailed post-synthetic millings of the photoprotective nanocomposite obtained, we aimed to study the mechanochemical effects on complex, hybridized layered double hydroxides (LDHs). Various physicochemical properties of the ground and the intact LDHs were compared by powder X-ray diffractometry, N2 adsorption-desorption, UV-Vis diffuse reflectance, infrared and Raman spectroscopy, scanning electron microscopy and thermogravimetric measurements. The data showed significant structural and morphological deformations, surface and textural changes and multifarious thermal behavior. The most interesting development was the change in the optical properties of organic LDHs; the milling significantly improved the UV light blocking ability, especially around 320 nm. Spectroscopic results verified that this could be explained by a modification in interaction between the LDH layers and the sulisobenzone anions, through modulated π-π conjugation and light absorption of benzene rings. In addition to the vibrating mill often used in the laboratory, the photoprotection reinforcement can also be induced by the drum mill grinding system commonly applied in industry.

A cutting-edge atomization-based methodology for enhancing formulation ability to resist photoaging

BackgroundSkin photoaging mainly occurs in exposed skin irradiated by ultraviolet rays from the sunlight. When exposed to ultraviolet rays, the skin will undergo certain changes to avoid damage. The inflammatory factors produced by light stimulation will induce melanocytes to produce more melanin, leading to the skin shows a rough, dark, dry, loose, and leathery appearance. In particular, when the skin is exposed to external damage and then received the damage of sunlight, such as after an aesthetic medicine treatment, it is more likely to produce post-inflammatory hyperpigmentation (PIH). However, there is a lack of a non-invasive and efficient solution. ObjectiveThe purpose of this study is to verify a new skincare method to resist photoaging. The essence itself has a very good effect in resisting photodamage, when it through atomized to skin, it showcases a non-invasive but better-result approach to skin care. Materials and MethodsThis study assessed anti-photoaging effects through in vitro (antioxidant, UVB protection, ROS tests) and human trials. In vitro results indicate the essence's efficacy. A randomized trial with 60 women (20-45 years, sensitive skin) compared atomized essence vs. smear control. After 28 days, atomized essence improved skin hydration, gloss, reduced redness, TiVi, TEWL, and UV protection. A 7-day test with Moyal Luminous Serum and Atomizer showed this skincare combo effectively prevents photodamage. ResultsThrough in vitro and human experiments, we have verified that the self-developed essence itself has a very good effect of anti-photoaging. Through further comparison of human efficacy tests, we found that with the support of an atomizer, the anti-photoaging effect of the essence has been improved. ConclusionEssence through atomization to resists photoaging, improves skin moisture, gloss, UV protection and reduces redness. Its non-invasive delivery ensures efficacy and user-friendliness.

Utilization of titanium dioxide (TiO2) nanoparticles to improve functionality and mechanical performances of cotton fabric

This study aims to produce high-quality functional cotton fabric through the deposition of nano TiO2. Here nanoparticles are deposited by the pad-dry-cure method with different recipes formulated using an acrylic binder and wax emulsifier together with TiO2 nanoparticles to observe the optimal effect on the final quality. The treated fabric is characterized by SEM, EDS, XRD, and FTIR. To analyze the results, the antimicrobial properties, UV protection, and crease resistance are measured as functional properties. Furthermore, tensile and tearing strength, frictional resistance, bending length, abrasion resistance, and pilling are determined as mechanical properties. The results confirm that the binder significantly affects on nano deposition and improves the mentioned functional characteristics. However, the deposition of nano TiO2 has deteriorated cotton's mechanical properties, and that degradation is intensified by the use of binder. This degradation problem is overcome by using the emulsifier as an auxiliary since the recipe having an emulsifier improves all the mechanical qualities of nano-treated cotton fabric. Particularly, the sample containing a binder and an emulsifier (Nano TiO2-3) ensures up to 97 % UV-ray blockage, 93 % antibacterial activity, and 9 % increase in tensile strength.

Accumulated melanin in molds provides wavelength-dependent UV tolerance.

Fungal contamination poses a serious threat to public health and food safety because molds can grow under stressful conditions through melanin accumulation. Although ultraviolet (UV) irradiation is popular for inhibiting microorganisms, its effectiveness is limited by our insufficient knowledge about UV tolerance in melanin-accumulating molds. In this study, we first confirmed the protective effect of melanin by evaluating the UV sensitivity of young and mature spores. Additionally, we compared UV sensitivity between spores with accumulated melanin and spores prepared with melanin biosynthesis inhibitors. We found that mature spores were less UV-sensitive than young spores, and that reduced melanin accumulation by inhibitors led to reduced UV sensitivity. These results suggest that melanin protects cells against UV irradiation. To determine the most effective wavelength for inhibition, we evaluated the wavelength dependence of UV tolerance in a yeast (Rhodotorula mucilaginosa) and in molds (Aspergillus fumigatus, Cladosporium halotolerans, Cladosporium sphaerospermum, Aspergillus brasiliensis, Penicillium roqueforti, and Botrytis cinerea). We assessed UV tolerance using a UV-light emitting diode (LED) irradiation system with 13 wavelength-ranked LEDs between 250 and 365nm, a krypton chlorine (KrCl) excimer lamp device, and a low pressure (LP) Hg lamp device. The inhibition of fungi peaked at around 270nm, and most molds showed reduced UV sensitivity at shorter wavelengths as they accumulated pigment. Absorption spectra of the pigments showed greater absorption at shorter wavelengths, suggesting greater UV protection at these wavelengths. These results will assist in the development of fungal disinfection systems using UV, such as closed systems of air and water purification.

Development of radish extract-loaded transfersomes blended sunscreen formulation for tyrosinase melanin and photoprotective sunscreening effect

Radish sprouts consist of a variety of active compounds, including phenolic compounds and ascorbic acid, which has antityrosinase activity, the key enzyme in melanogenesis. Furthermore, UV radiation cause hyperpigmentation and skin damage. The aim of this study was to develop radish sprouts extract (R)-loaded transfersomes for anti-aging and skin-whitening formulation. To provide UV protection, transfersomes were combined with sunscreen emulgel formulation. The physicochemical characteristics, biological activity, and cytotoxicity to skin cells of formulations were studied. The results showed that R-loaded transfersomes exhibited spherical nanovesicles and negative zeta potential. The vesicles were able to reduce tyrosinase activity and melanin content. However, transfersomes were safe to skin cells at low concentrations. By combining R-loaded transfersomes with sunscreen emulgels, the cytotoxicity of formulation decreased in addition to exhibiting stability under accelerated conditions. The formulation also absorbed UVA and UVB wavelengths with SPF and UVAPF values, due to the photoprotective properties of sunscreening agents. Furthermore, R slowly released from transfersome, emulsion matrix and gel base of the formulation. Thus, R-loaded transfersomes blended sunscreen emulgels could be applied as promising formulation with satisfactory activity for tyrosinase melanin and photoprotective sunscreening effect.

Preparation and characterization of peptide-modified core-shell fibrous substrates with UV-blocking properties for corneal regeneration applications

Effective UV protection is a key aspect of substrates directly exposed to UV radiation. Therefore, in the present study, fibrous substrates of core–shell morphology (PCL-core, PVP-shell) containing peptides based on tryptophan, tyrosine and cysteine (W6, YYC2 and YYC3) were prepared. Spectrophotometric studies showed UV absorption by peptides containing tyrosine and tryptophan in the UVB (up to 80%) and UVA (up to 40%) ranges. Cysteine, in turn, contributed to high antioxidant properties, confirmed by DPPH assay. The presence of peptides contributed to a nonwoven fabric characterized by the ability to absorb UV radiation and prevent the occurrence of oxidative stress (caused by the presence of free radicals). In turn, the increase in the surface zeta potential of the nonwoven after UV irradiation and higher thermal stability (demonstrated by DSC studies) indicated the crosslinking of the PVP layer under UVR, which further contributes to the increased protection of the nonwoven against its effects. In summary, obtained nonwoven exhibited functional similarity to the native cornea, providing a potential solution for enhancing corneal tissue engineering and regenerative medicine applications.

Long-lasting antistatic hydrophilic polyethylene terephthalate fabric using greener reagents

AbstractPolyethylene terephthalate (PET) is the most common synthetic polymer used in the textile sector by virtue of its unique superior performance attributes. However, the comfort characteristics of PET fabrics, such as their inadequate sweat-absorbing capability, low affinity for most dyestuff classes, and susceptibility to the accumulation of electrostatic charge, make them unfavorable compared to natural fibers. Rendering PET fabrics with hydrophilic and antistatic properties is difficult due to the lack of reactive functional groups. Herein, a long-lasting eco-friendly strategy to impart some desirable properties to PET fabrics was developed. The PET fabric was saponified in an aqueous caustic soda solution, followed by treatment with an amino acid, namely lysine, aspartic acid, serine, tyrosine, or cysteine, as a coupling agent, and eventually, the fabric was finished with the protein biopolymer gelatin using the pad-dry-cure method. The effects of treatment of PET fabric with the aforementioned reagents on its surface hydrophilicity, roughness, antistatic, thermal stability, ultraviolet protection, air permeability, yellowness, bending stiffness, and tensile properties were monitored. The discrepancy between the chemical structures of the untreated and finished fabrics was determined using Fourier transform infrared spectroscopy as well as by determining the carboxylic and nitrogen contents. The morphological and crystal structures of the treated fabrics were examined using scanning electron microscopy and X-ray diffraction pattern, respectively. The results indicate that a maximum add-on was obtained upon treatment of the saponified PET fabrics with 0.5 M lysine followed by 7.5% (on the weight of the fiber) gelatin using the pad-dry-cure method.The finished PET fabrics exhibited improved hydrophilic and antistatic properties with adequate protection against UV rays.Ingeneral, treatment of PET fabrics with gelatin, using a bi-functional amino acid as a coupling agent, is an effective and durable method to improve some performance and comfort features of PET fabric without having a remarkable negative effect on the fabric’s mechanical properties.

Solar energy harvesting using nanostructured ultrawideband absorber with nearly perfect thermal emission

In this article, nanostructured ultrawideband absorber is proposed for infrared to ultraviolet spectrum. The proposed three layered absorber structure formed of nickel, polyimide and nickel (Ni) material. The proposed unit cell volume is 90nm × 90 nm × 10.62 nm (0.0484λL× 0.0484λL× 0.00571λLnm3 where, λL is wavelength at lowest operating frequency). Absorption (A)≥ 90 % is achieved from 161.48 THz (1857.81 nm) to 3894.58 THz (77.03 nm) which covers infrared, visible and ultraviolet frequency bands. The average absorption 98.08 % is achieved over the entire operating frequency band. The absorption is also analyzed in different resonating patch geometry and using different substrate material. Due to the symmetricity of the octagonal patch geometry, the proposed structure is polarization insensitive and has incident angle (θ◦) stability up to 60° for absorption more than 80 %. The proposed solar absorber achieves 96.82 % solar absorption efficiency (ηA) and also achieves 94.61 %, 95.78 %, 96.31 % & 96.62 % thermal emission efficiency (ηE) at temperature 2000K, 2500K, 3000K & 3500K respectively. The suggested nanostructure absorber design works well across infrared, visible, and ultraviolet (UV) light, making it an efficient absorber for various uses like solar panels, detectors, solar energy harvesters, thermal devices, cloaking, solar power, sensors, and UV protection.