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Lignins released in the black liquors of kraft pulp mills are an underutilised source of aromatics. Due to their phenol oxidase activity, laccases from ligninolytic fungi are suitable biocatalysts to depolymerise kraft lignins, which are characterised by their elevated phenolic content. However, the alkaline conditions necessary to solubilise kraft lignins make it difficult to use fungal laccases whose activity is inherently acidic. We recently developed through enzyme-directed evolution high-redox potential laccases active and stable at pH 10. Here, the ability of these tailor-made alkaliphilic fungal laccases to oxidise, demethylate, and depolymerise eucalyptus kraft lignin at pH 10 is evidenced by the increment in the content of phenolic hydroxyl and carbonyl groups, the methanol released, and the appearance of lower molecular weight moieties after laccase treatment. Nonetheless, in a second assay carried out with higher enzyme and lignin concentrations, these changes were accompanied by a strong increase in the molecular weight and content of β–O–4 and β–5 linkages of the main lignin fraction, indicating that repolymerisation of the oxidised products prevails in one-pot reactions. To prevent it, we finally conducted the enzymatic reaction in a bench-scale reactor coupled to a membrane separation system and were able to prove the depolymerisation of kraft lignin by high-redox alkaliphilic laccase.

Enzymes can substitute harsh and energy-demanding chemical treatments for production of bio-based building blocks and products from wood processing. However, their properties need to be adapted to the extreme operation conditions (such as high T and pH) commonly used by these industries. Here, we summarize the main results obtained during the WoodZymes European Project (www.woodzymes.eu), which aimed to provide tailor-made extremozymes and extremozyme-based processes never assayed before in wood biorefineries. Novel extremophilic enzymes active on kraft lignin (laccases) and xylan (xylanases) were developed and produced at pilot or industrial scales. The enzymatic fractionation of kraft lignins using the METNINTM lignin refining technology, and the extremozyme-aided delignification and bleaching of kraft pulps were demonstrated at pilot scale. The resulting lignin and hemicellulose derived compounds were chemically characterized and applied as components of phenol-(lignin)-formaldehyde resins for wood panels and of polyurethane foams, or as papermaking additives. The new extremozymes were also applied to improve some of the latter applications. The techno-economic and environmental assessment of the new materials and processes, developed in WoodZymes project, showed that extremozyme-based processes led to clear benefits in energy savings during the refining of pulp or wood fibres, enabled lower addition of harsh chemicals (e.g. ClO2 during pulp bleaching), and resulted in a lower carbon footprint of the new bio-based products by substitution of fossil-derived components.

Xylanases can boost pulp bleachability in Elemental Chlorine Free (ECF) processes, but their industrial implementation for producing bleached kraft pulps is not straightforward. It requires enzymes to be active and stable at the extreme conditions of alkalinity and high temperature typical of this industrial process; most commercial enzymes are unable to withstand these conditions. In this work, a novel highly thermo and alkaline-tolerant xylanase from Pseudothermotoga thermarum was overproduced in E. coli and tested as a bleaching booster of hardwood kraft pulps to save chlorine dioxide (ClO2) during ECF bleaching. The extremozyme-stage (EXZ) was carried out at 90 °C and pH 10.5 and optimised at lab scale on an industrial oxygen-delignified eucalyptus pulp, enabling us to save 15% ClO2 to reach the mill brightness, and with no detrimental effect on paper properties. Then, the EXZ-assisted bleaching sequence was validated at pilot scale under industrial conditions, achieving 25% ClO2 savings and reducing the generation of organochlorinated compounds (AOX) by 18%, while maintaining pulp quality and papermaking properties. Technology reproducibility was confirmed with another industrial kraft pulp from a mix of hardwoods. The new enzymatic technology constitutes a realistic step towards environmentally friendly production of kraft pulps through industrial integration of biotechnology.

Inkjet-printing of metal nanoparticles is a particularly promising technique for the fabrication and modification of surfaces with a multifunctional nature. Recently copper sulfide nanoparticles (CuS NPs) have attracted wide interest due to a range of valuable properties including long term stability, photo-thermal activity, ease of synthesis and low cost. In the present study, printed CuS patterns were successfully fabricated on latex coated paper substrates and characterized by means of atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), UV–Vis-NIR spectroscopy, and grazing incidence X-ray diffraction (GID). The resulted patterns displayed pronounced photo-thermal effect under Near Infrared Irradiation (NIR) even with relatively low laser power. Finally, by utilizing an automated real-time imaging platform it was possible to verify that the CuS printed film was not cytotoxic to human dermal fibroblast cells (HDF). The pronounced photo-thermal properties and nontoxic nature of these printed low-cost flexible CuS films make them promising candidates for fabrication of devices with localized photo-thermal effect suitable for biomedical applications

The aim of this study was to prepare printable inks of the poorly water soluble drug indomethacin (IMC), fabricate printed systems with flexible doses and investigate the effect of ink excipients on the printability, dissolution rate and the solid state properties of the drug. A piezoelectric inkjet printer was used to print 1×1cm2 squares onto a paper substrate and an impermeable transparency film. l-arginine (ARG) and polyvinylpyrrolidone (PVP) were used as additional formulation excipients. Accurately dosed samples were generated as a result of the ink and droplet formation optimization. Increased dissolution rate was obtained for all formulations. The formulation with IMC and ARG printed on transparency film resulted in a co-amorphous system. The solid state characteristics of the printed drug on porous paper substrates were not possible to determine due to strong interference from the spectra of the carrier substrate. Yet, the samples retained their yellow color after 6months of storage at room temperature and after drying at elevated temperature in a vacuum oven. This suggests that the samples remained either in a dissolved or an amorphous form. Based on the results from this study a formulation guidance for inkjet printing of poorly soluble drugs is also proposed.

INTRODUCTION: There has been increased activity in the field recently regarding the development and research on various printing techniques in fabrication of dosage forms and drug delivery systems. These technologies may offer benefits and flexibility in manufacturing, potentially paving the way for personalized dosing and tailor-made dosage forms.\n\nAREAS COVERED: In this review, the most recent observations and advancements in fabrication of drug delivery systems by utilizing printing technologies are summarized. A general overview of 2D printing techniques is presented including a review of the most recent literature where printing techniques are used in fabrication of drug delivery systems. The future perspectives and possible impacts on formulation strategies, flexible dosing and personalized medication of using printing techniques for fabrication of drug delivery systems are discussed.\n\nEXPERT OPINION: It is evident that there is an urgent need to meet the challenges of rapidly growing trend of personalization of medicines through development of flexible drug-manufacturing approaches. In this context, various printing technologies, such as inkjet and flexography, can play an important role. Challenges on different levels exist and include: i) technological development of printers and production lines; ii) printable formulations and carrier substrates; iii) quality control and characterization; and iv) regulatory perspectives.

INTRODUCTION: There has been increased activity in the field recently regarding the development and research on various printing techniques in fabrication of dosage forms and drug delivery systems. These technologies may offer benefits and flexibility in manufacturing, potentially paving the way for personalized dosing and tailor-made dosage forms.\n\nAREAS COVERED: In this review, the most recent observations and advancements in fabrication of drug delivery systems by utilizing printing technologies are summarized. A general overview of 2D printing techniques is presented including a review of the most recent literature where printing techniques are used in fabrication of drug delivery systems. The future perspectives and possible impacts on formulation strategies, flexible dosing and personalized medication of using printing techniques for fabrication of drug delivery systems are discussed.\n\nEXPERT OPINION: It is evident that there is an urgent need to meet the challenges of rapidly growing trend of personalization of medicines through development of flexible drug-manufacturing approaches. In this context, various printing technologies, such as inkjet and flexography, can play an important role. Challenges on different levels exist and include: i) technological development of printers and production lines; ii) printable formulations and carrier substrates; iii) quality control and characterization; and iv) regulatory perspectives.

We combined conventional inkjet printing technology with flexographic printing to fabricate drug delivery systems with accurate doses and tailored drug release. Riboflavin sodium phosphate (RSP) and propranolol hydrochloride (PH) were used as water-soluble model drugs. Three different paper substrates: A (uncoated woodfree paper), B (triple-coated inkjet paper) and C (double-coated sheet fed offset paper) were used as porous model carriers for drug delivery. Active pharmaceutical ingredient (API) containing solutions were printed onto 1 cm × 1 cm substrate areas using an inkjet printer. The printed APIs were coated with water insoluble polymeric films of different thickness using flexographic printing. All substrates were characterized with respect to wettability, surface roughness, air permeability, and cell toxicity. In addition, content uniformity and release profiles of the produced solid dosage forms before and after coating were studied. The substrates were nontoxic for the human cell line assayed. Substrate B was smoothest and least porous. The properties of substrates B and C were similar, whereas those of substrate A differed significantly from those of B, C. The release kinetics of both printed APIs was slowest from substrate B before and after coating with the water insoluble polymer film, following by substrate C, whereas substrate A showed the fastest release. The release rate decreased with increasing polymer coating film thickness. The printed solid dosage forms showed excellent content uniformity. So, combining the two printing technologies allowed fabricating controlled-release oral dosage forms that are challenging to produce using a single technique. The approach opens up new perspectives in the manufacture of flexible doses and tailored drug-delivery systems. © 2012 Elsevier B.V. All rights reserved.

We combined conventional inkjet printing technology with flexographic printing to fabricate drug delivery systems with accurate doses and tailored drug release. Riboflavin sodium phosphate (RSP) and propranolol hydrochloride (PH) were used as water-soluble model drugs. Three different paper substrates: A (uncoated woodfree paper), B (triple-coated inkjet paper) and C (double-coated sheet fed offset paper) were used as porous model carriers for drug delivery. Active pharmaceutical ingredient (API) containing solutions were printed onto 1 cm × 1 cm substrate areas using an inkjet printer. The printed APIs were coated with water insoluble polymeric films of different thickness using flexographic printing. All substrates were characterized with respect to wettability, surface roughness, air permeability, and cell toxicity. In addition, content uniformity and release profiles of the produced solid dosage forms before and after coating were studied. The substrates were nontoxic for the human cell line assayed. Substrate B was smoothest and least porous. The properties of substrates B and C were similar, whereas those of substrate A differed significantly from those of B, C. The release kinetics of both printed APIs was slowest from substrate B before and after coating with the water insoluble polymer film, following by substrate C, whereas substrate A showed the fastest release. The release rate decreased with increasing polymer coating film thickness. The printed solid dosage forms showed excellent content uniformity. So, combining the two printing technologies allowed fabricating controlled-release oral dosage forms that are challenging to produce using a single technique. The approach opens up new perspectives in the manufacture of flexible doses and tailored drug-delivery systems. © 2012 Elsevier B.V. All rights reserved.

The piled steelgrid embankment is best suited for soil reinforcement of consolidating yards, where we can get the most use of its competitivity. Yards that consolidate are a national and an economical problem. Soil settlement generates large additions to use and repair costs. Well made surface strutures are ruined if the soil consolidates. There is a need for developing new soil construction methods. The soil reinforcement of large yards is quite expensive so more and more attention will progressively be used for soil construction in the near future. In Finland, Steelgrids are being used under highways to equalize soil consolidations, but they haven´t been directly used as a georeinforcement with the piled embankment. In this master´s thesis we analyse the use of steelgrid as a soil reinforcement method for a piled embankment. The thesis includes the steps of development, the measurement of the reinforcement method, the risk control of the method and the analysis of the experimental structure. The experimental structure that was built in association with the thesis is located in Vanttila, Espoo and it is used as a parking area for a local school. The structure was instrumentated and these results are analysed in this thesis. We found out that the structure is working mechanically. Advantages for this method are a short building time and low consolidation. Disadvantages should include poor repairbility under the steelgrid. The optimization of the method is not finished., Paalutettu teräsverkkopenger soveltuu parhaiten painuvien pihojen pohjanvahvistukseen, jossa sen kilpailukyvystä saadaan irti suurin hyöty. Painuvat pihat ovat kansantaloudellinen ongelma Suomessa. Maapohjan painuminen aiheuttaa suuria lisäyksiä käyttö- ja korjauskustannuksiin. Hyvin tehdyt pintarakenteet menevät aina piloille, jos pohjamaa painuu. Pihojen pohjanvahvistaminen nykyisillä menetelmillä on suhteellisen kallista, joten pihojen pohjarakentamiseen tullaan lähitulevaisuudessa kiinnittämään etenevästi huomiota. Teräsverkkoja käytetään Suomessa usein väylien alla tasaamassa painumia, mutta teräsverkkoja ei ole suoranaisesti aiemmin käytetty paalutetun penkereen yhteydessä geovahvisteena. Tässä diplomityössä käsitellään teräsverkkojen käyttöä paalutetun penkereen pohjanvahvisteena. Työ sisältää Tammet Oy:n kehityshankkeen vaiheet, pohjanvahvistusmenetelmän mitoituksen, menetelmän riskienhallinnan sekä koerakenteen analyysin. Diplomityön yhteydessä rakennettu koerakenne sijoittui Espoon Vanttilaan koulun parkkialueen pohjanvahvistukseksi. Koerakenne instrumentoitiin ja instrumentointituloksia analysoidaan tässä työssä. Koerakentamisesta selvisi, että menetelmän toimivuus mekaanisesti on hyvä. Menetelmän etuina voisi pitää lyhyttä rakennusaikaa ja pieniä painumia. Haasteena on verkkojen kunnallistekniikan yms. yhdistäminen. Rakenteen optimointi on vielä kesken.