Carcinogenic and non-carcinogenic risk assessment induced by pesticide residues in fresh pistachio in Iran based on Monte Carlo simulation.

This research is aimed at the analysis of 87 pesticides in 30 fresh pistachio samples prepared from stores in Iran by QuEChERS-ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The results showed at least one pesticide was in 67% of fresh pistachio samples. Kresoxim methyl residue was detected in 20 samples with average of 0.11 mg kg-1; this average is 2.2 times more than maximum residue limit (MRL). Buprofezin was recognized in five samples with average of 0.17 mg kg-1 was observed with 3.4 times more than MRL; hexaconazole and permethrin were recognized in three samples lower than MRL with an average residue of 0.030 and 0.028 mg kg-1, respectively. In addition, potential non-carcinogenic and carcinogenic health risk assessments were evaluated using probabilistic methods performed with the Monte Carlo simulation algorithm. The order of pesticide ranking based on hazard quotient (HQ) was hexaconazole > buprofezin > permethrin > kresoxim methyl. Total HQ (HI) was 2.0E-4 and for children, 9.0E-4. Hence, it means fresh pistachio consuming maybe not have significant short-term health risks for consumer. Ranking based on cancer risk (CR) was hexaconazole > kresoxim methyl > metalaxyl > permethrin > buprofezin. However, total CR due to pesticide residues was not higher than 1E-6 value (1.09E-9); therefore, consumers were not at significant risk of carcinogenicity in this product.

Global systematic review and meta-analysis on prevalence and concentration of aflatoxins in peanuts oil and probabilistic risk assessment.

Exposure to mycotoxins in food is largely unavoidable, and concerns about their health effects are growing. Consumption of vegetable oils such as peanuts oil has increased, hence several studies have been conducted on concentration of aflatoxins (AFs) in peanuts oil. Search was performed in Scopus and PubMed databases on prevalence and concentration of AFs in peanuts oil from 1 January 2005 to 15 April 29, 2022. Prevalence and concentration of AFs in peanuts oil was meta-analyzed based on country and type of AFs subgroups. In addition, health risk was calculated using monte carlo simulation method. Pooled prevalence of AFB1 in peanuts oil was 47.9%; AFB2, 46.45%; AFG1, 46.92% and AFG2, 54.01%. The Overall prevalence of AFTs was 49.30%, 95%CI (35.80-62.84%). Pooled concentration of AFB1 in peanuts oil was 2.30 µg/kg; AFB2, 0.77 µg/kg; AFG1, 0.07 µg/kg; AFG1, 0.28 µg/kg. The sort of country based on mean of MOEs in the adults consumers was Japan (47,059) > China (17,670) > Ethiopia (7,398) > Sudan (6,974) > USA (1,012) and sort of country based on mean of MOEs in the children was Japan (120,994) > China (46,991) > Ethiopia (19,251) > Sudan (18,200) > USA (2,620). Therefore, adults consumers were in considerable health risk in Ethiopia, Sudan and USA and for children in USA (MOE < 10,000).

Accuracy of noninvasive methods for the diagnosis of liver fibrosis in children with chronic viral hepatitis.

BACKGROUND: Liver biopsy is the reference standard for assessing liver fibrosis. Moreover, it is an invasive procedure. Transient elastography (TE) is an accurate, noninvasive method for evaluating liver stiffness as a surrogate of liver fibrosis. The aspartate aminotransferase to platelet ratio index (APRI) and Hyaluronic acid (HA) are noninvasive alternatives to liver biopsy for detecting hepatic fibrosis. This study aimed to identify the accuracy of APRI, HA, and TE concerning liver biopsy in children with chronic viral hepatitis. METHODS: This cross-sectional study included 50 children, 5-18 years with chronic viral hepatitis B (HBV) or hepatitis C (HCV) who underwent liver biopsy within nine months of laboratory tests, determining APRI & performing TE. Twenty healthy children of age and sex-matching patients were included as a control group for the serum HA levels. RESULTS: The histopathological findings of the studied cases showed seven cases with (F0) fibrosis, 36 cases with mild (F1,2), two children with moderate (F3,4), and five children with severe (F5,6). The median (IQR) of steatosis was 4 (three had HCV). When correlating TE, APRI, and HA values in all cases with their laboratory data, there was a positive correlation between ALT and APRI values (P-value = 0.000), a positive correlation between AST and HA values (P-value = 0.02), and a negative correlation between stiffness and APRI. The sensitivity of HA, APRI, and TE compared to fibrosis detected by histopathology was 60.5, 65.1, and 60.5%, and their specificity was 71.4, 57.1, and 85.7%, respectively. TE was significantly higher in a group with (moderate to severe) fibrosis. CONCLUSION: APRI, HA, and TE are good indicators of the presence of fibrosis almost with the same accuracy. TE is the only method to differentiate mild cases from those with significant fibrosis.

Highly Durable Antibacterial Properties of Cellulosic Fabric via ß-Cyclodextrin/Essential Oils Inclusion Complex.

Essential oils (EOS), which naturally come from plants, have significant antibacterial properties against a variety of pathogens, but their high volatility and poor water solubility severely restrict their use in the textile industry. In this study, an inclusion complex based on ß-cyclodextrin (ß-CD)/EOS was prepared by two different simple methods: pad dry cure (method 1) and pad batch (method 2). A glyoxal crosslinking agent was used for the fixation of the inclusion complexes on the surface of the fabric. Lavender, rosemary, salvia, and lemon essential oils were applied. The structure of the ß-CD/EOs inclusion complex was investigated using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and weight gain (%), which indicated that the ß-CD/EOs were successfully deposited on cellulose-based fabric. The results demonstrated that ß-CD enhanced the oils' scent stability, with the advantage of exhibiting no major change in the tensile strength or permeability of cotton. Lavender oil had the highest stability scent with a value of 3.25, even after 30 days of evaluation. The antibacterial activity showed that EOS/ßCD-impregnated fabrics for method 1 had an inhibition zone ranging from 33 to 23 mm, while the inhibition zone for method 2 ranged from 39 mm to 29 mm, indicating that our treatment was able to control the growth of bacteria, even after five washing cycles. This study confirmed that the EOs/ßCD inclusion-complex-deposited cotton fabric might hold further promise for medical and hospital use.

Prevalence, level and health risk assessment of mycotoxins in the fried poultry eggs from Jordan.

In the current study, level and prevalence of deoxynivalenol (DON), aflatoxin B1 (AFB1), zearalenone (ZEN), and ochratoxin A (OTA) in fried poultry eggs in Jordan was investigated. Poultry egg samples (n = 250) were collected from March to September 2017. The level of DON, AFB1, ZEN and OTA in the white and yolk of poultry eggs was measured using LC-MS-MS. The health risk assessment was calculated using Margin of Exposures (MOEs) for AFB1 and OTA and hazard index (HI) for ZEN and DON. The highest prevalence in yolk and white of eggs was related to ZEN (96.56 %) and OTA (97.44 %), respectively. Also, the highest level in white and yolk was related to DON (1.07 µg/kg) and DON (1.65 µg/kg), respectively. Level of DON in the yolk of eggs was significantly higher than white of eggs (P-value < 0.05). Risk assessment indicated that exposed population are at high risk of AFB1 (MOEs < 10,000) in fried poultry eggs.

Validation of HPLC and Enzyme-Linked Immunosorbent Assay (ELISA) Techniques for Detection and Quantification of Aflatoxins in Different Food Samples.

BACKGROUND: In Jordan as in other worldwide countries, mycotoxins are considered a serious national problem in food supplies. As a result, almost all nations are setting and adopting different regulations targeting the control of mycotoxins levels in the domestic food supply, including the problem of reliable sampling and analysis methods. OBJECTIVE: It is necessary to improve and give evidence of analytical abilities of laboratories within Jordan and developing countries enabling them to monitor mycotoxins effectively in food to overcome non-tariff obstacles. METHODS: We analyzed 40 samples from wheat, corn, dried fig and dried coffee beans for total aflatoxin content using High Pressure Liquid Chromatography (HPLC) and Enzyme Linked Immunesorbent Assay (ELISA) methods. RESULTS: 40% of samples from wheat, 60% from corn, 30% from dried fig, and 50% from dried coffee beans were found positive when speaking of total aflatoxins, with average values between 1.14 and 4.12 µg/kg. Obtained results allow considering all tested food samples as fit for human consumption if compared with the labeled regulatory limit of allowed aflatoxins in the European Union. In detail, the limit of detection and the limit of quantification for methods used in this study were significantly lower than the maximum limits established by the European Union. HIGHLIGHTS: The procedure used in this study is suitable for detection of mycotoxins at very low concentration.

Photocatalytic activity and antibacterial properties of linen fabric using reduced graphene oxide/silver nanocomposite.

Silver nanoparticles were in situ prepared on the surface of linen fabric coated by graphene oxide (GO). In the meantime, the reduction of silver nitrate on the GO-coated fabric led to the synthesis of reduced graphene oxide on the fabric. Two kinds of substrate (cotton and linen) were used. Both RGO/Ag and Ag/GO nanocomposites were added on cotton and linen fabrics through a conventional "pad-dry-cure" method. The chemistry and morphology of the coated surfaces were extensively characterized using Fourier-transformed infrared spectroscopy, energy-dispersive X-ray spectroscopy, and scanning electron microscopy. Resistivity measurements were used for assessing the conductivity. The UV protection properties and the photocatalytic activity of the coated fabrics against methylene blue dye were also investigated. The antibacterial activity was studied against Gram-positive S. aureus and B. subtilis and Gram-negative bacterial strains E. coli and P. aeruginosa by determining the zone of inhibition using the agar diffusion method. Methicillin-resistant Staphylococcus aureus (MRSA) has been responsible for many serious hospital infections worldwide. The fabrics showed superior antibacterial activity and successfully hindered the growth of pathogenic bacterial strains. This outcome suggested that both the RGO/Ag and Ag/GO nanocomposites-coated fabrics could be potentially applied in biomaterials and biomedical fields.

Wound dressing properties of cationized cotton fabric treated with carrageenan/cyclodextrin hydrogel loaded with honey bee propolis extract.

The current study was set to prepare a delivery system based on a mixture of biodegradable polymeric hydrogel (i.e., carrageenan (κ-CAR) and ß-cyclodextrin (ß-CD)) for encapsulating honey bee propolis extract (HBP). The crosslinking agent; glyoxal was incorporated to increase the insolubility of the HBP-loaded hydrogel to fit the cotton fabric treatments. The synthesized hydrogels were fully characterized to examine their surface and internal morphology and to visualize the chemical interaction between κ-CAR and ß-CD via SEM and FTIR techniques. The SEM pictures ensured the existent of many pores within the formed hydrogel. The swelling properties of κ-CAR/ß-CD/HBP were also studied in terms of glyoxal and HBP concentrations which displayed water holding with higher mechanical properties. Furthermore, in vitro release assessment of HBP from κ-CAR/ß-CD hydrogel was also studied at pH 7.6. Therefore, κ-CAR/ß-CD/HBP hydrogel was successfully used as fining compound for the cationized cotton fabrics. The data obtained emphasized that the surface of cationized cotton fabrics was deposited and penetrated with a film of κ-CAR/ß-CD/HBP. In addition, the antimicrobial activity of the treated cationized fabric was evaluated against many species of bacteria and fungus producing highly inhibition zone at lower concentrations of HBP. Accordingly, the cationized cotton fabric treated with κ-CAR/ß-CD/HBP has a high potential in the wound healing fabrics.

Aflatoxin M1 Levels in Raw Milk, Pasteurised Milk and Infant Formula.

The incidence of contamination of aflatoxin M1 (AFM1) in milk samples collected from the Jordanian market was investigated by using the competitive enzyme linked immunosorbent assay (ELISA) technique. A total of 175 samples were collected during 2014-2015. All tested samples were contaminated with various levels of AFM1 ranging from 9.71 to 288.68 ng/kg. The concentration of AFM1 in 66% of fresh milk samples was higher than the maximum tolerance limit accepted by the European Union (50 ng/kg) and 23% higher than the maximum tolerance limit accepted by the US (500 ng/kg). Percentages of contaminated raw cow, sheep, goat and camel milk exceeding the European tolerance limit were 60, 85, 75 and 0%, respectively. Of AFM1 contaminated pasteurised cow milk samples, 12% exceeded the European tolerance limit with a range of contamination between 14.60 and 216.78 ng/kg. For infant formula samples, the average concentration of AFM1 was 120.26 ng/kg (range from 16.55 to 288.68 ng/kg), the concentration of AFM1 in 85% of infant formula samples was higher than the maximum tolerance limit accepted by the European Union and the US (25 ng/kg).

Antifactor Xa levels vs. activated partial thromboplastin time for monitoring unfractionated heparin. A pilot study.

WHAT IS KNOWN AND OBJECTIVES: The two most common methods for monitoring unfractionated heparin (UFH) infusion are the activated partial thromboplastin time (aPTT) and the antifactor Xa heparin assay (anti-Xa). The purpose of this study is to compare the performance of an aPTT protocol vs. an anti-Xa protocol in adult patients as defined by the time to reach therapeutic range, the percentage of time the values were within the goal range and the number of times laboratory monitoring was conducted. We then analysed the discordance between paired values of anti-Xa and aPTT. METHODS: This was a single-centre prospective cohort pilot study conducted from 1 September 2013 to 31 May 2014. RESULTS: Eighty-five patients were treated with UFH infusion, aPTT monitoring (n = 48), anti-Xa monitoring (n = 37). The number of times aPTT and anti-Xa values were ordered was (median, IQR) 14 (2-34) vs 7 (2-76); P = 0·23. The time to reach therapeutic range in hours was (mean, SD) 22 (20) aPTT vs 15 (13) anti-Xa; P = 0·08. Therapeutic range (>50-100% of the time) was achieved in only 5 (10%) patients in the aPTT group vs. 21 (57%) in the anti-Xa group; P < 0·01. Supratherapeutic values (>50-100%) were observed in 38 (78%) patients in the aPTT group vs. 14 (38%) in the anti-Xa group; P < 0·01. The discordance between aPTT and anti-Xa was evaluated using 234 paired values from 37 patients. There was discordance between anti-Xa and aPTT values 57% of the time. Two patients had bleeding complications requiring blood transfusion or discontinuation of post-pilot protocol. WHAT IS NEW AND CONCLUSION: Utilizing an anti-Xa protocol to monitor heparin infusion showed favourable results compared with utilizing an aPTT protocol by maintaining values within the therapeutic goal range. The most common discordant pattern in our study was a disproportionate prolongation of aPTT to anti-Xa values. Patients with discordant values presenting with high aPTT to normal anti-Xa values may have an increased risk of bleeding complications.

Advancement in conductive cotton fabrics through in situ polymerization of polypyrrole-nanocellulose composites.

Current research was undertaking with a view to innovate a new approach for development of conductive - coated textile materials through coating cotton fabrics with nanocellulose/polypyrrole composites. The study was designed in order to have a clear understanding of the role of nanocellulose as well as modified composite thereof under investigation. It is anticipated that incorporation of nanocellulose in the pyrrole/cotton fabrics/FeCl3/H2O system would form an integral part of the composites with mechanical, electrical or both properties. Three different nanocellulosic substrates are involved in the oxidation polymerization reaction of polypyrrole (Ppy) in presence of cotton fabrics. Polymerization was subsequently carried out by admixing at various ratios of FeCl3 and pyrrole viz. Ppy1, Ppy2 and pp3. The conductive, mechanical and thermal properties of cotton fabrics coated independently with different nanocellulose/polypyrrole were investigated. FTIR, TGA, XRD, SEM and EDX were also used for further characterization. Results signify that, the conductivity of cotton fabrics increases exponentially with increasing the dose of pyrrole and oxidant irrespective of nanocellulose substrate used. While, the mechanical properties of cotton fabrics are not significantly affected by the oxidant treatment.

Radically new cellulose nanocomposite hydrogels: Temperature and pH responsive characters.

Innovation produced for synthesis of radically new stimuli-responsive hydrogels were described. The innovation is based on inclusion of cellulose nanowhiskers (CNW)-polyacrylamide (PAAm) copolymer in poly N-isopropyl acrylamide (PNIPAm) semi interpenetrating network (IPN) hydrogel. After being prepared as per free radical polymerization of AAm onto CNW, the as prepared copolymer was incorporated in a polymerization system, which comprises NIPAm monomer, bismethylene acrylamide (BMA) crosslinker, K2S2O8 initiator and TEMED accelerator, to yield CNW-PAAm-PNIPAm nanocomposite hydrogels. The latter address pH-responsive hydrogel as well as temperature-responsive. Hydrogels exhibit the highest equilibrium swelling ratio (ESR) in acidic medium (pH 4). Meanwhile they perform good swelling behavior and hydrophilicity at a temperature of 32°C. These hydrogels carry the characteristic features of CNW-PAAm copolymer as conducted from FTIR and TGA. The hydrogels are homogenous and well-proportioned network structure with highly connected irregular pores with a large size ranging from 30 to 100nm as concluded from SEM.

High frequency of splice site mutation in 21-hydroxylase deficiency children.

PURPOSE: Steroid 21-hydroxylase deficiency (21-OHD) is the common type of congenital adrenal hyperplasia (CAH) caused by defects in the CYP21A2 gene, as an autosomal recessive disease, genetic analysis has a prominent role in its diagnosis. Our objectives were to determine the prevalence of common mutations in a group of Egyptian patients with 21-OHD and their families using rapid methods, and also to detect the rate of deletion, duplication and conversions in CYP21A2 gene. METHODS: Rapid detection methods were used: allele-specific PCR for c.293-13A>G (g.659A>G), c.518T>A (p.I172N) variants and c.332_339del (8-bp deletion in exon 3), and real-time, quantitative PCR assay was used to detect deletion in the CYP21A2 gene. 29 Egyptian patients, 38 family members, and 20 healthy controls were all included in the study. RESULTS: The frequency of c.293-13A>G splice mutation was reported in 96.6 % cases, G allele had 2.5-folds higher risk to develop CAH than other alleles. The c.518T>A mutation was reported in 69 % cases, children carrying the mutant allele were 2.1 times more risk. The most frequent combined mutations detected were c.293-13A/C>G/c.518T>A in 58.6 % cases. CONCLUSION: The genetic analysis of the splice site mutation c.293-13A>G and c.518T>A variant can be used as good biomarkers for early detection of cases and carriers in 21-OHD CAH Egyptian children, since the methods used have rapid turnaround time.

Development of improved nanosilver-based antibacterial textiles via synthesis of versatile chemically modified cotton fabrics.

Cationization of cotton fabric form was effected by reacting the cellulose with 3-chloro-2 hydroxypropyl trimethyl ammonium chloride in presence of sodium hydroxide as per the pad dry cure method. Thus obtained cationized cotton cellulose was reacted with a reactive copolymer, namely, reactive ß-cyclodextrin grafted with polyacrylic acid (MCT-ßCD-g-PAA).Bridging of another copolymer, namely, ß-cyclodextrin grafted with polyacrylic acid (ßCD-g-PAA) to the cationized fabric using epichlorohydrin crosslinker was also performed. Inclusion of Ag nanoparticles in these three cotton substrates via treatment of the latter with colloid of Ag nanoparticles or through in situ formation of the former was exercised. Characterization of cotton fabric before and after being chemically modified was carried out using FTIR, XRD and SEM. Bacterial examination of the cationized cotton containing either (MCT-ßCD-g-PAA) or (ßCD-g-PAA) incorporated with Ag nanoparticles showed these substrates function against G+ve and G-ve bacteria. Ability of (MCT-ßCD-g-PAA) modified cotton to include hydrophobic molecules was examined.

In situ formation of silver nanoparticles for multifunctional cotton containing cyclodextrin.

This research presents new approach for functionalization of cotton fabrics against antibacterial. It comprises: (a) synthesis and characterization of two polymeric products that can referred to as reactive copolymer (monochlorotriazinyl-ß-cyclodextrin grafted with acrylic acid AA, MCT-ßCD-g-PAA) and normal copolymer (ß-cyclodextrin grafted with acrylic acid AA, ßCD-g-PAA), (b) reacting cotton with the reactive copolymer (c) treatment of the chemically modified cotton so-obtained with silver nitrate, (d) in situ reduction of silver ions using either the copolymer (ßCD-g-PAA) or a conventional reducing agent, namely, sodium borohydride, and (e) monitoring the antibacterial activity and resilience properties of the modified cotton fabrics. FTIR, SEM, and X-ray diffraction were employed to prove the structure of the synthesized polymeric products as well as micro structural changes in cotton cellulose as a result of the aforementioned treatments. The finished fabrics displayed superior antibacterial activity along with good fabric stabilization as indeed by fabric resilience.

Thermal responsive hydrogels based on semi interpenetrating network of poly(NIPAm) and cellulose nanowhiskers.

A hybrid hydrogel nanocomposite was developed based on semi interpenetrating network that was formed as a result of concurrent free radical polymerization of N-isopropylacrylamide (NIPAm) and methylenebis acrylamide (MBA) crosslinker along with cellulose nanowhiskers (CNWs). CNWs were synthesized through sulfuric acid hydrolysis and used in preparation of semi interpenetrating network (IPN). CNWs have considered as reinforcement materials for poly(NIPAm) because CNWs were distributed as strengthening entities in Poly(NIPAm). N-isopropylacrylamide was polymerized in presence of methylenebis acrylamide crosslinking agent using K2S2O8 as initiator at 700 C for 1h. The resulting hydrogel's structure, morphology, thermal sensitive property and swelling behavior were investigated. It was found that introducing CNWs into Poly(NIPAm) causes a huge increase in the value of equilibrium swelling ratio (ESR) as compared with the pure PNIPAm. The ESR ranges from 21.6g/g to 5 g/g as the swelling temperature changes from 310 °C to 340 °C; hence, the hydrogel exhibits a good responsive temperature at about 320 °C.

Preparation of multifunctional cationized cotton fabric based on TiO2 nanomaterials.

A novel approach for imparting multi-functional properties, i.e., UV-protecting, self-cleaning, water repellent as well as anti-bacterial properties onto cotton fabric is described. This research mainly deals with ecofriendly multifunctional cationized cotton fabrics using nanomaterialss based on TiO2 nanoparticles. In this study cotton fabric was cationized with two durable cationizing agent, 3-chloro-2-hydroxypropyl trimethyl ammonium chloride (Quat 188) and diallyl dimethyl ammonium chloride (DADMAC) using pad-batch method. The application of TiO2 nanomaterials on cotton 100% fabrics was achieved by using 1,2,3,4-butane tetracarboxilic acids [BTCA] as polycarboxilic cid cross linker with Sodium hypophosphite (SHP) as catalyst through conventional pad-dry-cure method. UV-protection, antibacterial and self-cleaning performances are investigated. Water repellent property of treated cationized cotton fabric post treated with stearic acid was also investigated.

Propolis induced antibacterial activity and other technical properties of cotton textiles.

Propolis is a gum gathered by honey bees from various plants; the honey bees use propolis to seal holes in their honey combs, smooth out the internal wall and protect the entrance against intruders. It is composed of 50% resin (flavonoids and related phenolic acid), 30% wax, 10% essential oils, 5% pollen and 5% various organic components. As a natural mixture, propolis is widely used in medicine, cosmetics and food. So far no attempts have been yet made to make use of propolis in the realm of textile finishing. Current work presents the first systemic study targeted to build up a scientific basis for production of cotton textiles having antibacterial activity and other useful properties by making use of propolis as eco-friendly finish within the scope of green strategy. Propolis extract solution (70/30 ethanol/water) of 10% concentration was prepared as the stock. Different amounts of the latter were used along with a crosslinking agent and catalyst for treatment of cotton fabrics as per pad-dry-cure technique. Antibacterial activity of the so treated fabrics was obtained through monitoring the efficiency of the interaction of propolis with cotton cellulose. This interaction was expressed as inhibition zone diameter after the treated fabrics were exposed to (G+ve) and (G-ve) bacteria. Other properties include crease recovery, tensile strength and elongation at break. Factors affecting these properties such as type, nature and concentration of the crosslinking agent, concentration of propolis, and conditions of curing were investigated. In addition characterization of the propolis containing modified cotton fabrics including demonstration of the antibacterial activity, SEM, FTIR, durability to washing, UV protection and water repellency were performed. Based on results obtained, it is concluded that application of propolis along with glyoxal and Al2(SO4)3catalyst using pad-dry (3min/80°C), cure (5/140°C) bring about cotton textile with superior antibacterial activity, water repellent and ease of care characteristics as well as UV protection. Tentative mechanism of the reaction of propolis with cotton in the presence of glyoxal was also reported.

Utilization of chitosan nanoparticles as a green finish in multifunctionalization of cotton textile.

Chitosan nanoparticles were synthesized through polymerization of CS at different concentrations with methacrylic acid (MAA) using K2S2O8 as initiator. This polymerization gave rise to suspension which was ice-cooled then subjected to severe centrifuging and the supernatant discarded to yield CS nanoparticles. Major characteristics of the so prepared CS nanoparticles namely size/distribution of the particles, their structural features, surface description and thermal stability were examined using DLS, FTIR, SEM and TGA, respectively. When CS nanoparticles were used as a finish for cotton fabrics with a crosslinking agent, the fabric displayed improved dyeability and thermal stability as well as antibacterial activity and UV protection. These latter two functionalities were significantly increased by post treatment of fabric with copper sulfate.

Synthesis and characterization of novel carboxymethylcellulose hydrogels and carboxymethylcellulolse-hydrogel-ZnO-nanocomposites.

New approach for preparation of CMC hydrogels was undertaken through reacting CMC with either malic, succinic or citric acid. Characteristics of the hydrogels, as monitored by the swelling behavior, FTIR, SEM, EDX, TEM and XRD were dependent on nature and concentration of the polycarboxylic acid, time and temperature of curing. The best practice achieved from these studies was harnessed to synthesize and characterize CMC hydrogel-ZnO-nanocomposites with additional study pertaining to the antibacterial activity of the nanocomposites. CMC hydrogel with excellent swelling behavior could be prepared by adding succinic acid (0.5%) to CMC solution then drying the obtained paste at 80 °C for 5 min followed by curing at 120 °C for 3 min. Similarly, addition of ZnNO3 solution to the CMC paste results in CMC hydrogel-ZnO-nanocomposites having biocidal activity to gram +ve and gram -ve bacteria.