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Contamination of waterways is of increasing concern, with recent studies demonstrating elevated levels of antibiotics, antidepressants, household, agricultural and industrial chemicals in freshwater systems. Thus, there is a growing demand for methods to rapidly and conveniently monitor contaminants in waterways. Here we demonstrate how a combination of paper microfluidic devices and handheld mobile technology can be used by citizen scientists to carry out a sustained water monitoring campaign. We have developed a paper-based analytical device and a 3 minute sampling workflow that requires no more than a container, a test device and a smartphone app. The contaminant measured in these pilots are phosphates, detectable down to 3 mg L-1. Together these allow volunteers to successfully carry out cost-effective, high frequency, phosphate monitoring over an extended geographies and periods., Competing Interests: The authors have declared that no competing interests exist.

Aim: To evaluate in vitro the antibacterial effect of a paper made of silver phosphate cellulose fibers (SPCF) on Staphylococcus aureus , the most common diabetic foot ulceration (DFU) pathogen when compared with other common commercial products., Methods: The antibacterial activity of SPCF samples was evaluated through time with cell counting on agar plates. SPCF samples were then compared with commercial wound care products currently in use in DFU treatments (Silvercel™, Acticoat 7, and Aquacel Ag Extra TM ) through time on agar plates (growth inhibition zones)., Results: After 6 hours, there was no viable bacterial cell detected on either plate ( p < 0.05). There was a net growth inhibition zone for SPCF samples but no significant difference between the two silver concentrations. Compared with common commercial products, SPCF paper provides results equal to Acticoat 7 ( p < 0.05). There was a net growth inhibition zone for SPCF samples but no significant difference between the two silver concentrations. Compared with common commercial products, SPCF paper provides results equal to Acticoat 7 ( p < 0.05). There was a net growth inhibition zone for SPCF samples but no significant difference between the two silver concentrations. Compared with common commercial products, SPCF paper provides results equal to Acticoat 7 (., Conclusions: These results have shown the efficiency of SPCF paper to eliminate Staphylococcus aureus in these conditions. SPCF papers are effective when compared with other common commercial products and could have an industrial potential in wound care. Infected DFU could benefit from the antibacterial effectiveness of SPCF, but more relevant experimentations related to foot ulcers are needed. Staphylococcus aureus , the most common diabetic foot ulceration (DFU) pathogen when compared with other common commercial products., Competing Interests: The authors declare that there are no conflicts of interest regarding the publication of this paper., (Copyright © 2020 Virginie Blanchette et al.)

In this communication a prototype of paper-based analytical device designed for simultaneous determination of orthophosphate and calcium ions, which levels are significant for hyperphosphatemia diagnostics, is presented. The laboratory-on-paper structure for two analytes detection was wax-printed on the surface of filter paper. These two-analyte disposable paper strips are combined with two paired LED-based fluorescence detectors and simple voltmeter used as recorder of analytical signal, what makes the developed device miniature, extremely low-cost, portable and user-friendly. Thus the developed device allows usage outside of specialized clinical laboratory. Moreover, each paper strip is disposable and its utilization is easy and fast and, additionally, burnt strip tests ensure waste non-infectious. The presented LED&Paper-based analytical device provides low detection limits: 1.4 μmol L -1 and 7.4 μmol L -1 for orthophosphate and calcium ions, respectively. The practical utility of the developed device for calcemia/phosphatemia diagnostics is demonstrated using control serum standards and real human serum., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)

Today, easy availability and efficient detection assays in low-resource settings are mandatory. Therefore, a smartphone-assisted paper-based detection strategy using eosin Y (EY)-embed ZIF-8 nanocomposite for phosphate (Pi), neutral red (NR) and heparin (HP) on site testing was fabricated. After adding the targets in a specific order, the prepared strips produced brilliant color transitions (astonishing colors, ranging from pistachio to bright yellow for Pi, from bright yellow to jacinth for NR and from jacinth to light orange for HP). These variation on tonality can be evaluated by the smartphone-based readout device (Color Assist App) through the ratio change of B/(R + G + B), which exhibits superior performance of on-site detection in wastewater, including high sensitivity (LOD is 0.015, 0.031 and 0.014 mM for Pi, NR and HP, respectively), ultra-fast response time and excellent selectivity. This strips and smartphone dual-mode monitoring strategy may offer a convenient idea to identify Pi, NR and HP, with great prospects for environmental wastewater applications. Additionally, the probe was enabled for bioimaging of Pi, NR and HP in living cells. Finally, the related anti-counterfeiting fluorescent ink of probe was proposed on schedule., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Paper manufacturers have long used silicone as the coating agent for release liners. However, silicone‐based release paper is very difficult to recycle due to covalent bonds between silicone and fibers. The most suitable solution to overcome this problem is to use alternative coating materials with adequate release properties, provided that they can be easily repulped in typical paper recycling facilities. We proposed a coating agent composed of phosphate esters and dimethylacetamide in order to manufacture a recyclable and efficient release paper. Analyses carried out on coated sheets showed that phosphate esters allowed the formation of a surface with adequate release properties (low peeling force and surface free energy). In addition, the residual adhesion values obtained with phosphate esters confirmed that they are well anchored on the backing paper surface, thus limiting the mass transfer to the adhesive tape. [ABSTRACT FROM AUTHOR]

The sensing field has shed light on an urgent necessity for field-deployable, user-friendly, sensitive, and scalable platforms that are able to translate solutions into the real world. Here, we attempt to meet these requests by addressing a simple, low-cost, and fast electrochemical approach to provide sensitive assays that consist of dropping a small volume (0.5 μL) of off-the-shelf alcohols on pyrolyzed paper-based electrodes before adding the sample (150 μL). This method was applied in the detection of phosphate after the formation of the phosphomolybdate complex (250-860 nm in size). Prior drops of isopropanol allow for the fast penetration of the sample through pores of this hydrophobic paper, delivering hindrance-free redox reactions across increasing active areas and ultimately improving the detection performance. The sensitivity (-1.9 10 -6 mA cm -2 ppb -1 ) and limit of detection (1.1 ppb) were improved, respectively, by factors of 33 and 99 over the data achieved without the addition of isopropanol, listing among the lowest values when compared with those results reported in the literature for phosphate (expressed in terms of the concentration of phosphorus). The approach enabled the quantification of this analyte in real samples with accuracies ranging from 87 to 103%. Furthermore, preliminary measurements demonstrated the successful performance of the electrodes with prior addition of other widely used alcohols, that is, methanol and ethanol. These results may extend the applicability of the method. In special, the scalability and eco-friendly character of the electrode fabrication combined with the sensitivity and simplicity of the analyses make the developed platform a promising alternative that may help to pave the way for a new generation of disposable sensors toward the daily monitoring of phosphate in water samples, thus contributing to prevent ecological side effects.

Porous magnesium oxide (MgO) films on carbon fiber paper (CF) have been successfully fabricated in a hydrothermal route at different calcination temperatures. The CF@MgO samples (CF@MgO-300, -400, and -500) show different morphologies with the increasing surface area from 3 for CF to 27 m 2  g -1 for CF@MgO-400. Among the four investigated samples, the CF@MgO-400 exhibits the highest phosphate removal ability (~ 1230 mg g -1 ) with promising applications for the large-scale utilization at low cost.

Vermitechnology is gaining recognition as an environmental friendly waste management strategy. Its successful implementation requires that the key operational parameters like earthworm stocking density be established for each target waste/waste mixture. One target waste mixture in South Africa is waste paper mixed with cow dung and rock phosphate (RP) for P enrichment. This study sought to establish optimal Eisenia fetida stocking density for maximum P release and rapid bioconversion of RP enriched cow dung-paper waste mixtures. E. fetida stocking densities of 0, 7.5, 12.5, 17.5 and 22.5 g-worms kg(-1) dry weight of cow dung-waste paper mixtures were evaluated. The stocking density of 12.5 g-worms kg(-1) resulted in the highest earthworm growth rate and humification of the RP enriched waste mixture as reflected by a C:N ratio of <12 and a humic acid/fulvic acid ratio of >1.9 in final vermicomposts. A germination test revealed that the resultant vermicompost had no inhibitory effect on the germination of tomato, carrot, and radish. Extractable P increased with stocking density up to 22.5 g-worm kg(-1) feedstock suggesting that for maximum P release from RP enriched wastes a high stocking density should be considered., (Copyright © 2014. Published by Elsevier Ltd.)

The preparation and evaluation of a simple paper-based device for the determination of reactive phosphate in natural and soil waters based on the formation of phosphomolybdenum blue is reported. Hydrophilic reagent zones were defined by printing filter paper with a hydrophobic paper-sizing agent using an inkjet printer. The molybdate/potassium antimony(III)-tartrate reagent and ascorbic acid reductant merged together from adjacent hydrophilic zones after spotting the liquid sample onto the paper. The colour intensity of the phosphoantimonylmolybdenum blue complex produced was measured using a flat bed scanner. Under optimal conditions, the paper-based device is characterised by a working range of 0.2-10 mg L(-1) P, limits of detection and quantitation of 0.05 and 0.16 mg L(-1) P, respectively, and repeatability of less than 2% RSD at 1 and 5 mg L(-1) P (n=10 and 8). There was no significant difference between the results obtained using the paper-based device and reference methods (t=0.0135, P (T≤t) two-tail=0.9892, df=38). In its optimum form, the paper-based device was stable for up to 15 day under ambient conditions, and up to 122 day when stored at ≤-20 °C. The small dimensions, minimal reagent consumption, low cost (a few cents), ease of operation and favourable analytical performance make the proposed paper-based device attractive for on-site environmental monitoring and analysis., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Material conversion from paper sludge ash (PSA) in NaOH solution was attempted to synthesize the adsorbent for removal of inorganic pollutants, such as Pb2+, NH4+ and PO4(3-) from aqueous solution. PSA of 0.5 g was added into 10 mL of 3 mol/L NaOH solution, and then heated at 80, 120, and 160 degrees C for 6-48 hr to obtain the product. PSA mainly composed of two crystalline phases, gehlenite (Ca2Al2SiO7) and anorthite (CaAl2Si2O8), and amorphous phase. Hydroxysodalite (Na6Al6Si6O24 8H2O) was formed at 80 degrees C, and anorthite dissolved, whereas gehlenite remained unaffected. Katoite (Ca3Al2SiO4(OH)8) was formed over 120 degrees C, and hydroxycancrinite (Na8(OH)2Al6Si6O24 2H2O) was formed at 160 degrees C, due to the dissolution of both gehlenite and anorthite. Specific surface areas of the products were almost same and were higher than that of raw ash. Cation exchange capacities (CECs) of the products were also higher than that of raw ash, and CEC obtained at lower temperature was higher. Removal abilities of products for Pb2+, NH4+, and PO4(3-) were higher than that of raw ash. With increasing reaction temperature, the removal efficiencies of Pb2+ and NH4+ decreased due to the decrease of CEC of the product, while removal efficiency for PO4(3-) was almost same. The concentrations of Si and Al in the solution and the crystalline phases in the solid during the reaction explain the formation of the product phases at each temperature.

Phosphate is an essential nutrient for heterotrophic bacteria, affecting bacterioplankton in aquatic ecosystems and bacteria in biofilms. However, the influence of phosphate limitation on bacterial competition and biofilm development in multispecies populations has received limited attention in existing studies. To address this issue, we isolated 13 adhesive bacteria from paper machine aggregates. Intergeneric inhibition of Pseudomonas aeruginosa WW5 by Serratia marcescens WW4 was identified under phosphate-limited conditions, but not in Luria-Bertani medium or M9 minimal medium. The viable numbers of the pure S. marcescens WW4 culture decreased over 3 days in the phosphate-limited medium; however, the mortality of S. marcescens WW4 was significantly reduced when it was co-cultured with P. aeruginosa WW5, which appeared to sustain the S. marcescens WW4 biofilm. In contrast, viable P. aeruginosa WW5 cells immediately declined in the phosphate-limited co-culture. To identify the genetic/inhibitory element(s) involved in this process, we inserted a mini-Tn5 mutant of S. marcescens WW4 that lacked inhibitory effect. The results showed that an endonuclease bacteriocin was involved in this intergeneric inhibition by S. marcescens WW4 under phosphate limitation. In conclusion, this study highlights the importance of nutrient limitation in bacterial interactions and provides a strong candidate gene for future functional characterisation., (© 2013 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.)

The effects of the addition of ammonium magnesium phosphate (AMP) to the paper of an electrically heated cigarette (EHC) prototype on smoke composition and toxicity were quantified and the underlying mechanisms investigated. Smoke from EHC prototypes with and without AMP and from conventional cigarettes, i.e. the University of Kentucky Standard Reference Cigarette 1R4F and eight American-blend market cigarettes, was compared. Endpoints for comparison were smoke chemistry, where toxic constituents were measured, cytotoxic activity, as measured in murine fibroblasts embryo cells by the Neutral Red Uptake Assay, and genotoxic activity, as measured in bacteria by the Salmonella Reverse Mutation Assay and in murine lymphoma cells by the TK Assay. The addition of AMP to the EHC led to a reduction of toxic substances and toxicological activity of approximately 30% compared to the EHC without AMP. Compared to the conventional cigarettes, the EHC with AMP showed reductions of 75-90%. Smoke from the EHCs generated in nitrogen atmospheres supplemented with different concentrations of ammonia and oxygen was assayed for its in vitro cytotoxicity and genotoxicity. The results indicate that the ammonia released by AMP at the heating site of the EHC is responsible for the reductions in cytotoxicity and mutagenicity for the EHC with AMP compared with the EHC without AMP. Thus, while the EHC approach distinctly reduces toxic smoke constituents compared to conventional cigarettes, the use of AMP in the paper of an EHC leads to further distinct reductions. In the study presented here, in vitro assays were used as quantitative tools to investigate toxicity-related mechanisms.

Pulp and paper mill wastewater is characterized by very high chemical oxygen demand (COD) values that inhibit the activity of microorganisms during biological oxidations. The electrochemical degradation of pulp and paper mill wastewater catalyzed by molybdenum and phosphate (Mo-P) modified kaolin with graphite as anode and cathode was investigated. The catalyst was characterized by XRD, XPS and SEM spectra and the effects of pH, metal ion and introduction of NaCl on the efficiency of the electrochemical degradation process were also studied. It was found out that the modified kaolin loaded with Fe(3+) had higher electrochemical catalytic activity in the electrochemical degradation of paper mill wastewater at pH 4. A 96% COD removal efficiency was obtained in 40min of electrochemical treatment of the wastewater at current density 30mAcm(-2). A possible mechanism for degradation of the mill wastewater constituents was also proposed.

Al-containing CaO-SiO(2)-H(2)O phases were prepared by hydrothermal treatment of mixtures of paper sludge ash (PSA) with various silica and calcia sources and their properties were determined with particular reference to the simultaneous uptake of ammonium and phosphate ions, which are implicated in the eutrophication of lakes and ponds. After examination of various silica and calcia sources, Ca(OH)(2) and SiO(2) sol were selected as the most appropriate starting materials. Dry milling was found to be superior to wet milling in avoiding contamination from the milling media during mixing. Nine samples with three different Ca/Si ratios and Al(2)O(3) contents were prepared with various mass ratios of Ca(OH)(2), PSA and SiO(2). The chemical compositions of the hydrothermal products of these mixtures moved towards the tieline of CaSiO(3)-PSA, with respect to the starting compositions. The major phase formed in all samples was poorly crystalline C-S-H(I), with hydroxysodalite also formed in the Al-containing mixtures. All the products showed a capacity for the simultaneous uptake of ammonium and phosphate ions. The saturated sorption capacities calculated from the Langmuir equation ranged from 0.9 to 2.4mmol/g for the ammonium ion and from 3.3 to 5.2mmol/g for the phosphate ion. Since the sorption capacities for both ions increased with increasing Ca contents of the product, substitution of Ca(2+) for NH(4)(+) and the formation of calcium phosphate phases such as apatite and brushite by precipitation are thought to be the main sorption mechanisms.

A study was undertaken to remove colour from a kraft mill's treated effluent in Kenya and determine the suitability of phosphate rock to replace wood ash during the electrochemical process. The electrochemical method alone, electrochemical combined with alum (ELCAL), wood ash leachate (ELCAS) and phosphate rock (ELPHOS) solutions at a rate of 165 to 1000 g/m3 were tested. Effluent characteristics were determined after complete removal of colour. Same reduction rates of TS (85%) and TSS (89%) were recorded by ELCAS and ELPHOS. However, ELPHOS removed more COD (86 to 91%) and more BOD (85 to 92%) than ELCAS. Furthermore, the pH of ELPHOS treated solution was 9.3, within the Kenya Local Government's allowable limit. Power reduction with ELCAS and ELPHOS varied between 53 to 73% and 49 to 69% respectively but the difference was not statistically significant. Overnight aeration further improved the quality of ELCAS and ELPHOS treated effluent, reducing BOD and COD values to 0 mg/l. ELPHOS cost ($0.29/m3) was nevertheless three times higher than that of ELCAS ($0.10/m3), mainly because of free wood ash. ELPHOS did not also increase effluent phosphorus. It was therefore recommended that various ways be explored in making ELPHOS more economical to replace ELCAS.

A procedure for the synthesis of a selective adsorbent for phosphate-containing biomolecules is described. The sorbent is based on Whatman chromatography paper, which is activated with epichlorohydrine, followed by the coupling of iminodiacetic acid to the active surface of the sorbent. The immobilized complex-forming chelating groups are saturated with ferric ions. The synthesized adsorbent is a counterpart to Chelating Sepharose and makes it possible to extend the use of immobilized ferric chelating groups for analytical purposes. It displays a high affinity towards compounds containing free terminal phosphate groups (phosphopeptides, nucleotides). The results of the binding experiments are compared to the corresponding data obtained with Chelating Sepharose gels.

The re-oxidation capacity of partially reduced heptamolybdo-pentavanado-phosphate polyanion (HPA-5(red) or heteropoly blue) by ozone in water and aqueous acetone solution has been examined under conditions simulating pulp bleaching process. Two oxidation stages/phases were revealed indicating the presence of two reactive states (forms) of catalyst in ozonation solution. The bulk of HPA-5(red) (ca. 90%) was completely recovered within a few first minutes of ozonation ([HPA](red)=0.5 mM; 0.39 mmol O(3)/min), whereas residual catalyst portion reacted very slowly (two orders lower rate) with ozone. Addition of organic solvent was shown to have a favorable effect on HPA-5(red) re-oxidation by ozone (k of 0.29 min(-1) vs. 0.43 min(-1) for ozonation, respectively, in water and 10%v/v acetone solution; pH 2), being evidently the principal reason for high efficiency of solvent-assisted HPA/O(3) pulp bleaching approach. The pH of reaction media (medium acidity) was found to have a notable effect on HPA-5(red) ozonation., (2010 Elsevier Ltd. All rights reserved.)

Cigarette smoke is a complex chemical mixture that causes a variety of diseases, such as lung cancer. With the electrically heated cigarette smoking system (EHCSS), temperatures are applied to the tobacco below those found in conventional cigarettes, resulting in less combustion, reduced yields of some smoke constituents, and decreased activity in some standard toxicological tests. The first generation of electrically heated cigarettes (EHC) also resulted in increased formaldehyde yields; therefore, a second generation of EHC was developed with ammonium magnesium phosphate (AMP) in the cigarette paper in part to address this increase. The toxicological activity of mainstream smoke from these two generations of EHC and of a conventional reference cigarette was investigated in two studies in rats: a standard 90-day inhalation toxicity study and a 35-day inhalation study focusing on lung inflammation. Many of the typical smoke exposure-related changes were found to be less pronounced after exposure to smoke from the second-generation EHC with AMP than to smoke from the first-generation EHC or the conventional reference cigarette, when compared on a particulate matter or nicotine basis. Differences between the EHC without AMP and the conventional reference cigarette were not as prominent. Overall, AMP incorporated in the EHC cigarette paper reduced the inhalation toxicity of the EHCSS more than expected based on the observed reduction in aldehyde yields.