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Antibacterial textile materials are widely used in daily life, but most are disposable products with poor antibacterial durability. N-halamine can rapidly inactivate microorganisms, has good stability, and shows great potential applications in antibacterial fabrics. In this study, an N-halamine monomer precursor was synthesized and treated onto PET fabrics. The treated PET fabrics were rendered antibacterial functionality after chlorination, and exhibited good antibacterial properties with inactivation rate of 100.0 % for both E. coli O157:H7 and S. aureus. After 50 wash cycles, the chlorinated treated PET fabrics could maintain 80.0 % antibacterial efficacy, demonstrating durable antibacterial properties. Storage stability and UV irradiation tests showed that the treated PET fabrics had remarkable regenerable properties. The reduction of the breaking strength was within 12 % after treatment, which is in a satisfying range in antimicrobial finishing.

Cellulose nanopaper (CNP) has been considered as a promising material with great application potential in diverse fields. However, the hydrophilic nature of CNP significantly limits its practical application. In order to improve its water resistance, we demonstrate a facile approach to functionalize CNP by impregnating it with chitosan (CS), followed by in situ polymerization of polypyrrole (PPy). The results indicate that the obtained CNP/CS/PPy shows excellent water resistance with the wet tensile strength of up to 80 MPa, which is more than 10 times higher than that of the pure CNP. Intriguingly, new features (e.g., electrical conductivity, antibacterial activity, and so forth) are achieved at the same time. The functionalized CNP/CS/PPy shows a high conductivity of 6.5 S cm-1, which can be used for electromagnetic interference shielding applications with a high shielding performance of around 18 dB. In addition, the CNP/CS/PPy exhibits good antibacterial activity toward Staphylococcus aureus and Escherichia coli, with the bacterial reductions of 99.28 and 95.59%, respectively. Thus, this work provides a simple and versatile approach to functionalize CNP for achieving multifunctional properties.

The numerous functional groups and dendritic structure of hyperbranched polymers render them for a wide range of applications. In this study, hyperbranched polymer Boltorn H20, containing abundant hydroxyl groups, was modified to prepare quaternary ammonium functionalized hyperbranched polymers, QAS-HPs. The synthesized QAS-HPs were coated on polyethylene terephthalate (PET) fabrics by electron beam radiation. The PET fabrics were endowed antimicrobial and hydrophilic properties after modification. The water contact angles of the modified PET fabrics were tested, and the results showed significant improvement in hydrophilicity. The results of antibacterial efficacy tests showed that the modified PET fabrics could inactivate 100% of Staphylococcus aureus (S.aureus) and 90.8% of Escherichia coli O157:H7 (E. coli O157:H7) with 30 min of contact time.

In this study, a novel method “spray-penetration-flocculation” was utilized to fabricate graphene oxide (GO)/quaternary ammonium salts (QAS) hybrid macroscopic aerogels to avoid the sudden precipitation of GO when it was combined with polycations and the collapse of three-dimensional monolith during the subsequent freeze-drying procedure. QAS could penetrate downward and induce the in situ flocculation of GO simultaneously, thus leading to the formation of GO-based hydrogel without any additional procedure requiring high-energy consumption. This unique method endowed an aerogel with hierarchically porous structure. The porous structure and low density made the aerogel a promising material for wastewater treatment with ultrahigh adsorption capacity toward soluble dyes, organic solvents and oils. Additionally, the QAS containing N-halamine groups loaded on GO functioned as an efficient biocidal component against Staphylococcus aureus (ATCC 6538) and Escherichia coli O157:H7 (ATCC 43895) and could inactivate the bacteria completely within 5 min of contact time. The as-constructed aerogel with these great attributes may serve as a promising candidate for water purification such as solvent recovery, oil/water separation and disinfection.

To obtain antibacterial properties for colored cotton fabrics, vat dyes were chosen to dye cotton because they can avoid serious discoloration during chlorination. In this study, we synthesized a reactive N-halamine precursor, 4-(4-(2,2,6,6-tetramethyl-4-piperidinol)-6-chloro-1,3,5-triazinylamino)-benzenesulfonate (BTMPT), and coated it on colored cotton fabrics that were dyed with three different vat dyes. The optimum pH for chlorination of the treated cotton fabrics was investigated. Chlorination at pH 11 achieved a small color difference and greater than 0.2% of active chlorine loading. When challenged, the chlorinated fabrics inactivated all inoculated Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) within 5 min. The treated cotton fabric had greater breaking strength than those treated with the traditional process, as well as good washing stability.

In this study, silane-modified polypyrrole (PPy) was coated onto cotton fabrics through a conventional “in situ polymerization” method. And by chlorination with NaClO solution, we obtained antimicrobial conductive PPy/Si–Cl–cotton fabrics. The PPy/Si–Cl–cotton fabrics were characterized by scanning electron microscopy, energy-dispersive spectroscopy, X-ray photoelectron spectroscopy, Fourier-transform infrared and thermogravimetric analysis. Also, the electrical conductivity property, antibacterial property, and ultraviolet light stability of the coated fabrics were tested. The PPy/Si–Cl–cotton fabrics showed antimicrobial and electrical conductivity properties when the chlorination time was up to 30 s. The chlorine content was 0.30 wt% and the resistance was 26.79 kΩ/cm. The PPy/Si–Cl–cotton fabrics (Cl+% 0.30) showed excellent antibacterial properties against 100% Staphylococcus aureus and 100% Escherichia coli O157:H7 were inactivated within 1 min of contact. Due to the proportional relationship of the electrical conductivity and chlorine content of the PPy/Si–Cl–cotton fabrics, the electrical conductivity of the PPy/Si–Cl–cotton fabrics can be used for monitoring the antimicrobial activity.

Effect of radio frequency (RF at 70, 80 and 90 °C) pretreatment on production and characterisation of sweet potato protein hydrolysates (SPPH) prepared using Alcalase (ALC), Protease (PRO) and the combination of ALC + PRO was investigated. RF highly improved degree of hydrolysis (DH) and enhanced antioxidant activity of all SPPH produced by ALC, PRO and the combination as compared to traditional water bath (WB) heating pretreatment (P

An N-halamine precursor, 3- (2-aminoethyl)-5, 5-dimethylhydantoin (ADMH), was grafted onto the oxidized cellulose (OC) to obtain OCADMH. The OC was prepared by selective oxidation of microcrystalline cellulose (MCC). SEM, FTIR, Solid 13C NMR and XRD analyses were used to characterize the target product. The chlorinated OCADMH was added into polyvinyl alcohol (PVA) solution to form uniform films by the solution casting method. And the PVA, PVA/OCADMH and PVA/OCADMH-Cl films were characterized by SEM, FTIR and XRD. The antibacterial activities of PVA/OCADMH-Cl films against S aureus and E coli O157:H7 were tested. The testing results showed that the chlorinated PVA/OCADMH films could inactivate all inoculated S aureus (ATCC 6538) and E coli O157: H7 (ATCC 43895) within 60 and 30 min of contact time, respectively.

An N-halamine precursor monomer, cyanuric chloride (CYCH), was attached onto nanocrystalline cellulose (NCC) and chloropropyltriethoxysilane (CPTES) was used as a crosslinking agent to prepare hydrogels based on the modified nanocrystalline cellulose. The aerogels were obtained by freeze-drying the hydrogels followed by chlorination. Microscopic investigation of the morphology revealed that the aerogels were porous with three-dimensional web-like microstructure. Their hydrophobic properties were efficient in removing dodecane spills from water. The response of the chlorinated aerogels challenged against Staphylococcus aureus (ATCC 6538) and Escherichia coli O157:H7 (ATCC 43895) showed their potent antimicrobial activities in killing these two bacterial species. Their properties of being ultralight, highly porous, hydrophobic, reusable, superabsorbing, and antibacterial efficient render these aerogels promising materials for cleaning up oil spills and inactivating bacteria.

Polymeric N-halamine precursors, cationic poly((3-acrylamidopropyl) trimethylammonium chloride) (CHP) and anionic poly(2-acrylamido-2-methylpropane sulfonic acid sodium salt) (AHP), were synthesize...

Chickens with high populations of various microorganisms arrive at processing facilities. Salmonella species are one of the important foodborne pathogens commonly found in poultry products. Various intervention strategies are implemented during poultry processing to reduce microorganisms in the products, including pre-scald bird brushes, multi-stage scalding, antimicrobial applications, etc. In this study, the effects of adding sodium dodecyl sulfate (SDS) to chlorine (Cl) and peracetic acid (PAA) against Salmonella were investigated. In addition, the efficacy of wax coating the skin to reduce Salmonella attachment was studied. Skin samples were collected following the 4 different methods of (1) euthanized-dry hand-de-feathered carcasses, (2) carcasses rinsed in tap water and mechanically de-feathered, (3) carcasses soft scalded and mechanically de-feathered, and (4) from carcasses hard scalded and mechanically de-feathered. It was shown that 0.5% SDS was able to reduce Salmonella both loosely (34, 28, 42, and 13%, respectively) and firmly (29, 39, 32, and 53%, respectively) attached in the 0.005% Cl-treated samples, but did not increase antimicrobial efficacy of 0.2% PAA. Moreover, carnauba wax coating significantly (P ≤ 0.05) reduced Salmonella attachment on all 4 types of chicken skins, 1.57, 0.71, 0.74, and 0.84 log cfu/sample on dry hand de-feathered, tap water rinsed, soft-scalded and hard-scalded chicken skins, respectively. Beeswax coating did not affect Salmonella attachment regardless of types of chicken skins. Overall, the addition of SDS improved antimicrobial activity of Cl, but not for PAA. Moreover, carnauba wax coating was an effective intervention to reduce Salmonella on chicken skin.

In this study, cotton fabrics with improved antibacterial efficiency and hydrophobic properties were prepared with the coatings of N-halamine siloxanes, ZnO, and silane precursors by the ultrasonic-assisted dipping-padding assembly technique. The coated cotton fabrics were characterized by FT-IR, SEM, XRD and XPS. The chlorinated cotton fabrics showed good hydrophobicity with water contact angle of 139o ± 2o. With the addition of ZnO in the N-halamine coatings, the chlorinated samples showed good antibacterial efficacy and could inactivate both all inoculated Escherichia coli O157:H7 (ATCC 43895) and Staphylococcus aureus (ATCC 6538) within 10 min. The chlorinated samples also showed good viability to mammalian cells. The stabilities of the coated cotton towards UV light and washing cycles and mechanical properties were investigated. Over 69% of the chlorine was retained after the equivalent of 25 machine washes. The N-halamine siloxanes coating of cotton with ZnO nanoparticles significantly enhanced the UV stability. In addition, the coated cotton fabrics maintained high tensile strength and fair air permeability.

Antibacterial cotton fabrics were prepared with 3-allyl-5,5-dimethylhydantoin (ADMH) by UV photoinitiated thiol-ene click chemistry after 3-mercaptopropyltriethoxysilane (MPTES) was introduced on the surface of cotton fabrics. The treated cotton fabrics were characterized by SEM, FT-IR and EDS. After chlorination with diluted sodium hypochlorite, the treated samples showed good antibacterial efficacy against S. aureus and E. coli O157:H7. About 106 of S. aureus and E. coli O157:H7 could be completely inactivated within 1 min and 5 min of contact, respectively. Compared to the control samples, the antibacterial treatment method used in this study only had a minor effect on the tensile strength of cotton fabrics. Besides, the treated cotton fabrics showed good storage stability and 77 % of the active chlorine remained after 30 days. After exposure to bleach solution, almost all of the active chlorine was restored. The prepared antimicrobial cotton fabrics showed good washing and UV light stability.

Effects of thermal (boiling, steaming and autoclaving), microwave and ultrasonication pretreatments on the production of sweet potato protein hydrolysates (SPPH) through in vitro gastrointestinal digestion (GID) were investigated. All pretreatments significantly increased the degree of hydrolysis (DH), antioxidant activities and molecular weight (MW) microwave, steaming > boiling > ultrasonication (P

In order to prepare multifunctional fibrous membranes with hydrophobicity, antibacterial properties and UV resistance, we used silica and titanium dioxide for preparing SiO2@TiO2 nanoparticles (SiO2@TiO2 NPs) to create roughness on the fibrous membranes surfaces. The introduction of TiO2 was used for improving UV resistance. N-Halamine precursor and silane precursor were introduced to modify SiO2@TiO2 NPs to synthesize SiO2@TiO2-based core@shell composite nanoparticles. The hydrophobic antibacterial fibrous membranes were prepared by a dip-pad process of electrospun biodegradable polyhydroxybutyrate/poly-e-caprolactone (PHB/PCL) with the synthesized SiO2@TiO2-based core@shell composite nanoparticles. TEM, SEM and FT-IR were used to characterize the synthesized SiO2@TiO2-based core@shell composite nanoparticles and the hydrophobic antibacterial fibrous membranes. The fibrous membranes not only showed excellent hydrophobicity with an average water contact angle of 144° ± 1°, but also appreciable air permeability. The chlorinated fibrous membranes could inactivate all S. aureus and E. coli O157:H7 after 5 min and 60 min of contact, respectively. In addition, the chlorinated fibrous membranes exhibited outstanding cell compatibility with 102.1% of cell viability. Therefore, the prepared hydrophobic antibacterial degradable fibrous membranes may have great potential application for packaging materials.

An N-halamine siloxane precursor γ-(β-hydroxyl-γ-5,5- dimethylhydantoin)aminopropyltrithoxysilane (abbreviated as GHAPA) was synthesized in this study. GHAPA was mixed with PVA solution to prepare PVA/GHAPA cross linked film with an antimicrobial function. The obtained PVA/GHAPA cross linked film was characterized by TGA, DSC and XRD. Upon dilute household bleach treatment, the chlorinated PVA/GHAPA cross linked film could inactivate Staphylococcus aureus and Escherichia coli O157:H7 completely with concentrations of 4.57 × 107cfu and 2.70 × 107cfu within 5 and 10 min, respectively, and 99.9995% of Escherichia coli O157:H7 could be inactivated within 5 min. The antimicrobial results showed that the chlorinated films substantially outperformed the unchlorinated control samples. The biocidal films may serve as potential materials for food packaging and biomedical applications.

The FDA Produce Safety Rule states that water used for irrigation purposes, likely to come into contact with the edible portion of fruit and vegetables, must not exceed a defined limit of Escherichia coli populations. Although aquaponics has not been included in this guideline, it is worth investigating to establish a baseline for facilities to reference in produce production. Two microbial assays were performed, one a decoupled media-based aquaponics system over one year and another on a decoupled nutrient film technique (NFT) aquaponics system over 16 days. Water was sampled from each system over time to analyze changes of E. coli and coliforms. The geometric mean (GM) and statistical threshold variable (STV) were calculated based on E. coli populations from the irrigation source in each system. From the first experiment, it was determined, based on the FDA Produce Safety Rule, that E. coli must be monitored more closely from June to January as they were above the advised limit. The second experiment determined that E. coli and coliforms in the water significantly decreased over 16 days. Water should be held for 8 d and up to 16 d to reduce the likelihood of foodborne pathogens to contaminate produce.

In this study, we synthesized a novel N-halamine precursor, sulfuric acid mono-[2-(4-[4-chloro-6-(2-[4,4- dimethyl-2,5-dioxo-imidazolidin-1-yl]-ethylamino)-[1,3,5]triazin-2-ylamino]-benzenesulfonyl)-ethyl] ester sodium (TB), which contains two reactive groups of monochloro triazine reactive groups and bis-sulphatoethylsolphone reactive groups. The structure of TB is similar to iso-bifunctional group reactive dyes and could be coated on cotton fabrics by covalent bonds through a reactive dyeing process. The cotton coated with TB was characterized by FTIR and SEM. After chlorination, the treated cotton fabrics showed excellent antibacterial efficacy and inactivated all inoculated S. aureus (ATCC 6538) and E. coli O157: H7 (ATCC 43895) within 1 min of contact. Over 85 % of tensile strength retained both in warp and weft directions after treatment and chlorination. Almost 80 % of active chlorine can be regained by treating with household bleach after extensive washing and long time storage.

In this study, graphene oxide modified polymeric N-halamine precursor was coated onto cotton fabrics through a conventional “dipping-drying” method. The functionalized cotton fabrics were in-situ reduced by treating with L-ascorbic acid. The coated cotton fabrics were then treated with household bleach for enhanced antibacterial activity. After chlorination, the coated cotton fabrics showed an UPF value of 132, and the value increased after oxidative chlorine being consumed. The coated fabrics were also endowed with great hydrophobicity, with values higher than 140°, indicating great self-cleaning ability. The chlorinated fabrics could completely inactivate inoculated S. aureus and E. coli O157:H7 within 1 min and 5 min with 5.07 and 5.18 log reductions, respectively. Due to the proportional relationship of the electrical conductivity and chlorine content of the cotton/rGO-PSPH-Cl fabric, the electrical conductivity of cotton/rGO-PSPH-Cl fabric can be used for monitoring the antimicrobial activity.

Fibrous membranes based on polyhydroxybutyrate/poly-e-caprolactone (PHB/PCL) blends were obtained by electrospinning. Composite nanoparticles produced from N-halamine precursors and silane precursors were used to modify silica hydrosol which were obtained by the condensation of tetraethylorthosilicate followed the Stober method. The produced composite nanoparticles were characterized by TEM and FT-IR. The dip-pad process was used to coat the synthesized silica composite nanoparticles onto the fibrous membrane. The coated PHB/PCL fibrous membranes were characterized by SEM, FT-IR and TGA. After chlorination, the chlorinated fibrous membranes showed excellent hydrophobicity with water contact angle of 151° ± 1° and exhibited effective antimicrobial activity against Escherichia coli O157:H7 and Staphylococcus aureus with 99.95% and 99.91% bacterial reduction within 60 min of contact time, respectively. The coated membranes showed good stability and durability toward UVA light exposure and storage. The cell biocompatibility test indicated that the membranes have no cytotoxicity. Therefore, the designed antibacterial fibrous membranes with super hydrophobicity may have great potential for use in food packaging and biomedical materials.

N-halamine polymers have been successfully attached surfaces of mesoporous materials. The modified mesoporous materials have been applied on the modification of cotton. Soaking in household bleach, the coated cotton shows good antimicrobial efficacy against S. aureus and E. coli O157:H7. The chlorinated samples could completely inactivate 100% S. aureus within 10 min, and 99.99% E. coli O157:H7 within 30 min. The chlorinated sample had better platelet adhesion and red blood cell cohesion than the control sample. The blood clotting index and fluid absorptive property of the samples enhanced after coating with modified mesoporous materials, indicating that the coated sample can prevent wound infection from bacteria and control hemorrhaging simultaneously. The coating of the modified mesoporous materials and N-halamines on cotton has not affect the bioactivity of cotton in the simulated body fluid. The active chlorine of the coated sample decreased 30% after soaking in the whole blood for 1 h. Considering the good antimicrobial efficacy against microorganisms and hemostasis property in blood control of the prepared materials, they have potentials for biomedical applications in wound dressing.

The antimicrobial activity of N -halamine, 1-chloro-2,2,5,5-tetramethyl-4-imidazolidinone (MC) loaded absorbent pads in meat packaging was investigated. Absorbent pads treated with MC reduced the levels of total aerobic bacteria, Pseudomonas spp., and lactic acid bacteria to under the detection limit (2 log CFU/g) for day 0 and day 1. On days 4, 7 and 11, the microbial loads were significantly reduced ( p p

The antimicrobial activity of 1-chloro-2,2,5,5-tetramethyl-4-imidazoidinone (MC), a nonbleaching N-halamine compound, was investigated on materials commonly used in broiler production, including stainless steel, galvanized metal, aluminum, plastic, and pressure-treated wood. MC aqueous solutions at 0.02, 0.04, and 0.06% were challenged with Salmonella Typhimurium and Campylobacter jejuni at 6 log CFU/mL, resulting in complete inactivation of both bacteria in 30 min with 0.06% MC. Follow-up experiments were performed using test materials treated with 0.1 and 1% MC and challenged with Salmonella Typhimurium and C. jejuni at 6 log CFU per coupon. Stability of MC on the various surfaces of testing materials was assessed, and the chlorine content of the materials was measured using iodometric thiosulfate titration over a 4-week period. Antimicrobial activities were evaluated by a sandwich test on each sampling day during 4 weeks of storage. On the samples treated with 1% MC, bacteria at 6 log CFU per coupon were completely inactivated within 2 h of contact time. The antimicrobial activity extended to 4 weeks, and the active chlorine atoms in the treated materials decreased from the initial 10

Polypyrrole (PPy) coating was electrochemically synthesized on carbon steel using sulfonic acids as dopants: p-toluene sulfonic acid (p-TSA), sulfuric acid (SA), (±) camphor sulfonic acid (CSA), sodium dodecyl sulfate (SDS), and sodium dodecylbenzene sulfonate (SDBS). The effect of acidic dopants (p-TSA, SA, CSA) on passivation of carbon steel was investigated by linear potentiodynamic and compared with morphology and corrosion protection performance of the coating produced. The types of the dopants used were significantly affecting the protection efficiency of the coating against chloride ion attack on the metal surface. The corrosion performance depends on size and alignment of dopant in the polymer backbone. Both p-TSA and SDBS have extra benzene ring that stack together to form a lamellar sheet like barrier to chloride ions thus making them appropriate dopants for PPy coating in suppressing the corrosion at significant level. Further, adhesion performance was enhanced by adding long chain carboxylic acid (decanoic acid) directly in the monomer solution. In addition, PPy coating doped with SDBS displayed excellent biocidal abilities against Staphylococcus aureus. The polypyrrole coatings on carbon steels with dual function of anti-corrosion and excellent biocidal properties shows great potential application in the industry for anti-corrosion/antimicrobial purposes.

This paper presents a method that combines surface swab sampling and wireless biosensing for rapid detection of foodborne pathogens on solid surfaces. The method can be applied to any surfaces, including the surfaces of food processing tables and fresh produce, for food safety improvement. Surface swab sampling is an inexpensive and easy-to-use method of collecting pathogens. A desired area or the whole area of a target surface (if needed) can be swabbed to collect pathogens rapidly. In this study, five commercially available swabs were compared. We first investigated the water absorption capacities of the swabs and then analyzed the efficiencies of capture and release of a model pathogen, Salmonella Typhimurium. Plate counting was employed to quantify the initially inoculated cells and collected cells by surface swabbing, and the efficiency of capture and release was calculated.

The surfaces of materials fabricated from stainless steel are challenging to functionalize with antimicrobial moieties. This work demonstrates that stainless steel surfaces can be modified with an N-halamine-based copolymer in order to obtain antimicrobial activity. In this regard, a copolymer (HACM) of 2-acrylamido-2-methyl-1-(5-methylhydantoinyl)propane and 3-cloro-2-hydroxypropyl methacrylate was synthesized and grafted onto a stainless steel surface via covalent attachment. Synthesized monomers and copolymers were characterized by NMR, FTIR, and XPS spectral analyses. Upon treatment with dilute bleach, the stainless steel surfaces were rendered antimicrobial, possessing a sufficient amount of chlorine content and excellent stability and durability. The modified stainless steel samples inactivated 6 logs of Staphylococcus aureus and Escherichia coli O157:H7 bacteria within 15 min of contact time. Stabilities of the coatings toward washing and UVA exposure were also studied. The stainless steel samples ...

In this study, polyhydroxybutyrate/poly(butyleneadipate-co-terephthalate) (PHB/PBAT) nanofibrous membranes were produced by electrospinning the blends of biodegradable PHB and PBAT. The antibacterial hydrophobic nanofiber membranes were obtained by grafting 1-allylhydantoin and perfluorooctyl acrylate onto the PHB/PBAT membranes. The prepared nanofibrous membranes were chlorinated with chlorine bleach and characterized by scanning electron microscopy, Fourier transform infrared, and thermogravimetric analysis. The chlorinated nanofibrous membranes exhibited efficient antimicrobial activity against Escherichia coli O157:H7 (ATCC 43895) and Staphylococcus aureus (ATCC 6538) with 6.08 and 5.78 log reduction, respectively. The contact angle of this antibacterial membrane was 123.1° ± 1.9°. The treated membranes showed good stability and durability towards UV-A light exposure and storage. Therefore, our designed antibacterial hydrophobic nanofibrous membranes may have great potential for use in food packaging.

To achieve textile dyeing and functional finishing in one process, a bleach-resistant reactive dye precursor to anti-bacterial N-halamine was synthesised by reacting a type of dichlorotriazine reactive dye with 4-amino-2,2,6,6-tetramethylpiperidine. The synthesised compound, which can be transformed to an N-halamine molecule by exposure to dilute bleach solution, was used to dye cotton fabrics. After exposure to a dilute sodium hypochlorite solution, dyed cotton fabrics showed excellent anti-bacterial properties against Staphylococcus aureus and Escherichia coli O157:H7, facilitating a ca. 6-log reduction in bacteria within a short period of contact. Compared with the dichlorotriazine reactive dye, the reactive dye precursor demonstrated comparable dyeing properties including exhaustion and fixation values. No differences in rub fastness, wash fastness or bleach fastness were detected between fabrics dyed with, respectively, dichlorotriazine reactive dye and the reactive dye precursor to N-halamine.

Inorganic–organic composites have received considerable attention due to their combined properties. In this study, a N-halamine precursor poly[5,5-dimethyl-3-(3′-triethoxysilylpropyl)-hydantoin] (PSPH) was synthesized and used for the production of inorganic–organic hybrid particles after reacting with nano-TiO2 by a sol–gel process. The hybrid particles were characterized by FT-IR, XRD, and TGA-DTG. After chlorinated in the dilute sodium hypochlorite solution, antibacterial Cl-PSPH-TiO2 nanoparticles (NPS) could be obtained and used for production of polyvinyl alcohol (PVA) composite membranes. The synthesized PSPH-TiO2/PVA composite membranes were characterized by SEM, FT-IR, XRD, and TGA-DTG. Meanwhile, antibacterial property, UV light stability, mechanical properties, and storage stability of the composite membranes were tested. The antibacterial composite membranes with Cl-PSPH-TiO2 could inactivate 99.97% of Staphylococcus aureus (3.03 logs) and 100% of Escherichia coli O157:H7 (6.12 logs) within 30 min. The antibacterial composite membranes also showed good UV light stability, regeneration ability, and excellent storage stability.

5,5-Dimethyl-3-((3’-triethoxysilylpropylamido)propyl)hydantoin (Si-Hy), a novel N-halamine precursor, has been synthesized in this work. The traditional pad-dry-cure process was used to coat the produced Si-Hy onto cotton fabrics. The coated fabric was characterized by SEM, FTIR and XPS. After exposure to chlorine bleach, the treated fabric presented good antimicrobial ability. The chlorinated sample demonstrated potent antibacterial ability against S. aureus (ATCC 6538) and E. coli O157:H7 (ATCC 43895) in brief contact time. Sixty seven percent of oxidative chlorine was retained and over 85 % of chlorine could be recharged after storage for 15 days and rechlorination. The antibacterial materials with good biocidal efficacies have potential applications in the healthcare industry.

This study aimed to develop novel, biodegradable, antiseptic-loaded and low-cost scaffolds using a direct ink writing (DIW) technique for antibacterial applications. Polylactic acid/cellulose acetate (PLA/CA) mixtures with different composition ratios were prepared, and the effect of CA content on the rheological behaviors of the inks was investigated. The printability of the prepared DIW inks was improved with the addition of the appropriate amount of CA, since the formation of hydrogen bonding 3D network between PLA and CA. As a result, a liquid form ink consisting of majority of PLA and minority of CA which was prepared and printed for the first time through DIW technique. Afterwards, the antimicrobial agent, 1-chloro-2,2,5,5-tetramethyl-4-imidazolidinone (MC) was incorporated into the inks for preventing bacterial infections, which showed excellent stability and effective antibacterial activity against S. aureus and E. coli O157:H7 in a short time. Owning the ease of fabrication and the biocidal property, our 3D printed scaffolds will have a wide range of potential applications in the field of food packaging, communal facilities, medical equipments, and biomedical materials.

Intelligent packaging can provide better preservation and advanced convenience for consumers. In this study, corn starch and polyvinyl alcohol (PVA) were used to produce films. Two easily accessible anthocyanin sources-purple sweet potato extracts (PSPE) and red cabbage extracts (RCE), were added respectively to evaluate their potential of indicating food freshness. Film incorporated with PSPE or RCE showed distinguishable color changes in different buffers. Water vapor permeability (WVP) was not significantly (p > 0.05) affected by addition of RCE or lower level PSPE. As the extract content increased, a significant (p

The aim of this study was to develop novel nanofibrous membranes based on the quaternary ammonium N-halamine chitosan (CSENDMH) and polyvinyl alcohol (PVA) for antibacterial and hemostasis wound dressing. To improve the antimicrobial properties of nanofibrous membranes, a new chitosan-quaternary ammonium N-halamine derivative was successfully synthesized, and the structure was analyzed by 1H NMR and 13C NMR, fourier transform infrared (FTIR) spectroscopy, and elemental analysis. The morphological and water absorption ability studies showed that the membrane had a uniform bead-free network and high porosity structure like natural extracellular matrix as well as high hydrophilicity. For in vitro evaluation of the hemostatic effect, the membranes showed excellent blood clotting capacity, especially the PVA/CSENDMH membranes. The antimicrobial assay demonstrated excellent antibacterial activity of nanofibrous membranes against both gram-negative and gram-positive bacteria. Furthermore, the cytocompatibility assay results indicated that human fibroblasts could adhere and proliferate on the membranes, thus corroborating their biocompatibility.

Cutaneous hemorrhage often occurs in daily life which may cause infection and even amputation. This research aims to develop a novel chitosan dressing impregnated with ZnO/N-halamine hybrid nanoparticles for quick antibacterial performance, outstanding hemostatic potential, high porosity, and favorable swelling property through combining sonication and lyophilization processing. After 30 days of storage, about 90% bacterial cell viability loss could be observed toward both Gram-positive

The survival on tomato fruits ( Lycopersicum esculentum ) of a rifampicin-resistant strain of Salmonella montevideo (Centers for Disease Control and Prevention [CDC] isolate G4639), the alleged source of the 1993 multistate outbreak of salmonellosis, was affected by inoculum dose and inoculation site (unbroken surface or wounds and stem scars), as well as by the medium (distilled water, Butterfield's buffer, or trypticase soy broth [TSB]) used to deliver the bacterium, This bacterium inoculated at 4 log

Aspergillus candidus ATCC 44054 grown without agitation produced more kojic acid in the modified Czapek-Dox liquid medium than cultures shaken at 100 rpm. Of the three culture media tested, yeast extract-sucrose medium permitted more kojic acid production by the fungus than modified Czapek-Dox liquid medium or Tadera medium. Maximal kojic acid (57-59 mg/ml) was produced in the yeast extract-sucrose medium on days 9-12. No aflatoxin by the fungus was detected.

Fresh specialty crop produce such as tomatoes, blueberries, strawberries, sprouts, cantaloupes, lettuce and leafy greens account for more instances of foodborne illness than any other food category. Recent announcements to consumers, by the United States (U.S.) Centers for Disease Control (CDCs), to discard all Romaine lettuce because of bacterial contamination has resulted in hundreds of millions of dollars in losses to growers and processors. Unfortunately, current microbiological testing of samples of specialty crops (whole fruits, leaves of spinach, etc.), as specified by FDA’s Bacteriological Analytical Manual (BAM), requires at least 48 hours to perform the complicated, time-consuming and costly steps of soaking, , concentration, enrichment, plate count or PCR to detect pathogens on these samples. Further complicating the BAM analyses are the realities that: 1) both PCR and ELISA are unable to distinguish between live and dead cells and 2) only a few samples out of as many as 100,000 fruits, vegetables or leaves of multi-ton batches of produce can be BAM tested. A Non-clogging Biomolecular Phage Filter has been developed to simultaneously capture, concentrate and isolate small numbers of pathogens from large volumes of produce wash water. This phage filter can then be evaluated to screen for live versus dead cells and ID the specific pathogen in minutes. Capture efficiencies of greater than 94% have been demonstrated.