Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.966
Filtrar
1.
Carbohydr Polym ; 292: 119701, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35725185

RESUMO

Solar energy-based steam generation holds immense potential to tackle the problem of 1.1 billion people lacking access to freshwater and 2.7 billion experiencing freshwater scarcity at least one month a year. Efficient, portable, and universal photothermal materials are required for popularity of solar-driven evaporation systems. Herein, a facile one-pot process based on solution-processed vapor phase polymerization is adopted to fabricate polypyrrole-coated cellulose nanocrystals (CNC-PPy). The CNC-PPy dispersed in water is used as an ink (CNC-PPy ink) to create photothermal layers. The developed ink is readily laminated on diverse substrates utilizing a common paintbrush that firmly attached without any delamination after drying. The optimized cellulose membrane (6 coating cycles) presents an excellent evaporation rate of 1.96 Kg m-2 h-1 with corresponding light-to-vapor efficiency of 88.92 % at 1 sun. In addition, the CNC-PPy display excellent antibacterial and antifouling properties in powder and laminated forms against E. coli and S. aureus.


Assuntos
Incrustação Biológica , Polímeros , Antibacterianos/química , Antibacterianos/farmacologia , Incrustação Biológica/prevenção & controle , Celulose/química , Celulose/farmacologia , Escherichia coli , Humanos , Tinta , Polímeros/química , Polímeros/farmacologia , Pirróis/química , Staphylococcus aureus , Vapor
2.
Comput Intell Neurosci ; 2022: 7574231, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35676957

RESUMO

Ink element is one of the unique cultural symbols in China, which has profound cultural heritage and spiritual connotation. Animation is a form of art design, and it is a good way to convey and express information in an intuitive artistic image. The use of ink and wash elements for animation design has important value and significance in the start of Chinese culture. It can develop animation design, innovate animation creation forms, and can highlight Chinese style. In this article, we have studied the creation process, creation format, and creation method of using angular digital technology to make ink VR design. It combines art and technology and combines practical experience with wireless sensors. Based on HTML5 interactive technology, we have studied its advantages more deeply, better introduced the theme of ink element animation, solved the problem of realizing ink effect in 3D virtual environment, and better introduced ink animation in virtual reality environment. During the production process, students will learn how to simulate digital objects, render ink and wash effects, build a virtual environment in the later stage, and explore the knowledge, operation, and meaning of ink and wash elements and the animation design process. This paper studies the wireless sensor and HTML5 interactive technology and applies it to the design of ink and wash animation VR, aiming to promote its vigorous development and application.


Assuntos
Interface Usuário-Computador , Realidade Virtual , Humanos , Tinta , Aprendizagem , Tecnologia
3.
Molecules ; 27(11)2022 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-35684430

RESUMO

Due to the increasing tattoo practicing in Eastern countries and general concern on tattoo ink composition and safety, the green tattoo inks Green Concentrate by Eternal, for European and "for Asia Market Only" were analyzed, under the premise that only the former falls under a composition regulation. A separation of the additives from the pigment was carried out by successive extraction in solvents of different polarities, i.e., water, acetone and dichloromethane. The solid residues were analyzed by IR and Raman spectroscopies, the liquid fractions by GC/mass spectrometry. The relative pigment load and element traces were also estimated. We found that the European and the Asian inks are based on the same pigment, PG7, restricted in Europe, though at different loads. They have a similar content of harmful impurities, such as Ni, As, Cd and Sb and both contain siloxanes, including harmful D4. Furthermore, they have different physical-chemical properties, the European ink being more hydrophilic, the Asian more hydrophobic. Additionally, the Asian ink contains harmful additives for the solubilization of hydrophobic matrices and by-products of the phthalocyanine synthesis. Teratogenic phthalates are present as well as chlorinated teratogenic and carcinogenic compounds usually associated to the laser treatment for removal purposes, to a larger extent in the European ink. The composition of the inks does not seem to reflect regulatory restrictions, where issued.


Assuntos
Tinta , Tatuagem , Ásia , Corantes/química , Espectrometria de Massas , Análise Espectral Raman/métodos
4.
Pharm Res ; 39(6): 1267-1279, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35661083

RESUMO

PURPOSE: Semi-solid extrusion (SSE) 3D printing has potential pharmaceutical applications for producing personalised medicine. However, the effects of ink properties and drug incorporation on the quality of printed medication have not been thoroughly studied, particularly for porous geometries. This study aimed to investigate the effects of the presence of solid drug particles in SSE inks on the printing quality of porous structures. METHOD: The rheological behaviour of model inks of paracetamol (PCM)-hypromellose (HPMC) with different drug loadings were investigated and correlated to their printing qualities. RESULTS: For the inks with PCM loading above the drug solubility in which suspended solid drug particulates were present, the results confirmed that PCM loading and particle size significantly affected the ink viscosities at a low shear rate. At a low shear rate, the highest viscosity was identified when the highest drug loading and the smallest PCM particles were incorporated into the inks. However, the results indicated that the SSE printing parameters and printing quality of porous structures (with less porous structural deformation) have no clear correlation with the shear viscosity data, but a strong correlation with the dynamic oscillatory rheology of the inks. CONCLUSION: The key rheological parameters including storage modulus, loss modulus and complex viscosity of the ink increased with increasing drug loading for the inks containing solid drug particles. However, decreasing the particle size did not have a clear effect on the oscillatory rheology of the inks which can be potentially used for optimising the SSE 3D printing quality of porous geometries.


Assuntos
Tinta , Impressão Tridimensional , Preparações Farmacêuticas , Porosidade , Reologia
5.
Forensic Sci Int ; 336: 111321, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35526403

RESUMO

As a custom in China, a visible fingerprint pressed with red seal ink on a signature represents personal confirmation of a document. This custom makes ink fingerprints important evidence for individual identification in the forensic practice of questioned document examination. Recently, forged ink fingerprints using stamps or silica gel fingerprint models have emerged. Consequently, detecting and profiling the pattern of biological substances in visible fingerprints on questioned documents is crucial to prove that a fingerprint was imprinted by its real owner. To solve this problem, a desorption electrospray ionization mass spectrometry (DESI-MS) method was developed to detect the biological substances in ink fingerprints on paper. In the positive ion mode, more signals were detected, but the interference from the seal inks could not be ignored. In the negative ion mode, the ion detected in the sweat latent fingerprints at m/z 187 presented high chemical specificity for MS imaging. It was most likely a borate compound in human sweat. Using this biomarker, the fingerprint pattern was successfully profiled and the hand-imprinted fingerprint was clearly distinguished from the stamp-imprinted one. This method can help in determining the authenticity of ink fingerprints on questioned documents in forensic practice.


Assuntos
Tinta , Espectrometria de Massas por Ionização por Electrospray , China , Humanos , Espectrometria de Massas por Ionização por Electrospray/métodos , Suor
6.
J Am Chem Soc ; 144(22): 9949-9958, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35637174

RESUMO

Surfaces with patterned biomolecules have wide applications in biochips and biomedical diagnostics. However, most patterning methods are inapplicable to physiological conditions and incapable of creating complex structures. Here, we develop a mechanochemical lithography (MCL) method based on compressive force-triggered reactions. In this method, biomolecules containing a bioaffinity ligand and a mechanoactive group are used as mechanochemical inks (MCIs). The bioaffinity ligand facilitates concentrating MCIs from surrounding solutions to a molded surface, enabling direct and continuous printing in an aqueous environment. The mechanoactive group facilitates covalent immobilization of MCIs through force-triggered reactions, thus avoiding the broadening of printed features due to the diffusion of inks. We discovered that the ubiquitously presented amino groups in biomolecules can react with maleimide through a force-triggered Michael addition. The resulting covalent linkage is mechanically and chemically stable. As a proof-of-concept, we fabricate patterned surfaces of biotin and His-tagged proteins at nanoscale spatial resolution by MCL and verify the resulting patterns by fluorescence imaging. We further demonstrated the creation of multiplex protein patterns using this technique.


Assuntos
Biotina , Impressão , Biotina/química , Tinta , Ligantes , Impressão/métodos , Proteínas/química
7.
J Fr Ophtalmol ; 45(6): 608-611, 2022 Jun.
Artigo em Francês | MEDLINE | ID: mdl-35570166

RESUMO

Tattooing of the glove is an old practice used 2000 years ago on the cornea to improve the appearance of unsightly corneal scars. Since 2007, tattoo artists have been performing scleral tattoos, also called "eyeball tattoos," despite the risks involved and the disapproval of health authorities and the medical community. We report the case of a 30-year-old man with bilateral black ink scleral tattoos who came to our ophthalmologic emergency service with episcleral nodules, which had appeared at the ink injection sites. The clinical course stabilized with topical anti-inflammatory treatment. Similar cases have been reported in the literature, in one of which the patient underwent surgical excision of a similar lesion. Histological analysis showed a lympho-histiocytic reaction without any signs of malignancy. To date, 20 cases of scleral tattoos have been reported in the international literature, often with severe complications. We see, on the one hand, complications related to perforating trauma, and on the other hand, acute and chronic complications inherent to the products used. Scleral tattooing is gaining popularity around the world despite significant risk exposure, including traumatic, inflammatory, immune, infectious and probably long-term neoplastic consequences. Ophthalmologists must be aware of this practice and its consequences in order to make the most appropriate therapeutic decisions.


Assuntos
Tatuagem , Adulto , Córnea , Humanos , Tinta , Masculino , Esclera/cirurgia , Tatuagem/efeitos adversos
8.
Sensors (Basel) ; 22(9)2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35591162

RESUMO

Herein, we review printing technologies which are commonly approbated at recent time in the course of fabricating gas sensors and multisensor arrays, mainly of chemiresistive type. The most important characteristics of the receptor materials, which need to be addressed in order to achieve a high efficiency of chemisensor devices, are considered. The printing technologies are comparatively analyzed with regard to, (i) the rheological properties of the employed inks representing both reagent solutions or organometallic precursors and disperse systems, (ii) the printing speed and resolution, and (iii) the thickness of the formed coatings to highlight benefits and drawbacks of the methods. Particular attention is given to protocols suitable for manufacturing single miniature devices with unique characteristics under a large-scale production of gas sensors where the receptor materials could be rather quickly tuned to modify their geometry and morphology. We address the most convenient approaches to the rapid printing single-crystal multisensor arrays at lab-on-chip paradigm with sufficiently high resolution, employing receptor layers with various chemical composition which could replace in nearest future the single-sensor units for advancing a selectivity.


Assuntos
Gases , Tinta , Dispositivos Lab-On-A-Chip , Gases/análise , Reologia
9.
Toxicol Ind Health ; 38(7): 417-434, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35592919

RESUMO

Today, tattooing has become very popular among people all over the world. Tattooists, with the help of tiny needles, place tattoo ink inside the skin surface and unintentionally introduce a large number of unknown ingredients. These ingredients include polycyclic aromatic hydrocarbons (PAHs), heavy metals, and primary aromatic amines (PAAs), which are either unintentionally introduced along with the ink or produced inside the skin by different types of processes for example cleavage, metabolism and photodecomposition. These could pose toxicological risks to human health, if present beyond permissible limits. PAH such as Benzo(a)pyrene is present in carbon black ink. PAAs could be formed inside the skin as a result of reductive cleavage of organic azo dyes. They are reported to be highly carcinogenic by environmental protection agencies. Heavy metals, namely, cadmium, lead, mercury, antimony, beryllium, and arsenic are responsible for cancer, neurodegenerative diseases, cardiovascular, gastrointestinal, lungs, kidneys, liver, endocrine, and bone diseases. Mercury, cobalt sulphate, other soluble cobalt salts, and carbon black are in Group 2B, which means they may cause cancer in humans. Cadmium and compounds of cadmium, on the other hand, are in Group 1 (carcinogenic to humans). The present article addresses the various ingredients of tattoo inks, their metabolic fate inside human skin and unintentionally added impurities that could pose toxicological risk to human health. Public awareness and regulations that are warranted to be implemented globally for improving the safety of tattooing.


Assuntos
Mercúrio , Hidrocarbonetos Policíclicos Aromáticos , Tatuagem , Aminas/toxicidade , Cádmio , Carcinógenos/toxicidade , Humanos , Tinta , Metais , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Fuligem , Tatuagem/efeitos adversos
10.
Chem Commun (Camb) ; 58(49): 6894-6897, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35638877

RESUMO

A polyurethane-gelatin methacryloyl (PU-GelMA) hybrid ink was developed as a photo-crosslinkable elastic hydrogel. With the additional acrylic monomer, the ink can be tuned to accommodate elasticity and printability. Attributed to the shear-thinning properties of GelMA, PU-GelMA was preferable for extrusion printing. 3D-constructs were printed by direct extrusion or by using a sacrificial scaffold to resemble the vascular networks. The proliferation of endothelial cells on the PU-GelMA hydrogel indicated decent biocompatibility and potential utilization in artificial vessels.


Assuntos
Tinta , Poliuretanos , Células Endoteliais , Gelatina , Hidrogéis , Metacrilatos , Impressão Tridimensional , Engenharia Tecidual , Tecidos Suporte
11.
ACS Biomater Sci Eng ; 8(6): 2589-2597, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35608818

RESUMO

Silk fibroin (SF) is an attractive material for composing bioinks suitable for three-dimensional (3D) bioprinting. However, the low viscosity of SF solutions obtained through common dissolution methods limits 3D-bioprinting applications without the addition of thickeners or partial gelation beforehand. Here, we report a method of 3D bioprinting low-viscosity SF solutions without additives. We combined a method of freeform reversible embedding of suspended hydrogels, known as the FRESH method, with horseradish peroxidase-catalyzed cross-linking. Using this method, we successfully fabricated 3D SF hydrogel constructs from low-viscosity SF ink (10% w/w, 50 mPa s at 1 s-1 shear rate), which does not yield 3D constructs when printed onto a plate in air. Studies using mouse fibroblasts confirmed that the printing process was cell-friendly. Additionally, cells enclosed in printed SF hydrogel constructs maintained > 90% viability for 11 days of culture. These results demonstrate that the 3D bioprinting technique developed in this study enables new 3D bioprinting applications using SF inks and thus has a great potential to contribute to tissue engineering and regenerative medicine.


Assuntos
Bioimpressão , Fibroínas , Animais , Bioimpressão/métodos , Hidrogéis , Tinta , Camundongos , Impressão Tridimensional , Viscosidade
12.
Int J Biol Macromol ; 209(Pt B): 2020-2031, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35500781

RESUMO

The current study provides a comprehensive rheology study and a survey on direct ink writing of xanthan gum/cellulose nanocrystal (XG/CNC) bio-inks for developing 3D geometries that mimic soft tissue engineering scaffolds' physical and mechanical properties. The presence of CNC was found to be a critical prerequisite for the printability of XG bio-inks; accordingly, the hybrid XG/CNC bio-inks revealed the excellent viscoelastic properties that enabled precise control of hydrogel shaping and printing of lattice structures composed of up to eleven layers with high fidelity and fair resolution without any deformation after printing. The lyophilized 3D scaffolds presented a porous structure with open and interconnected pores and a porosity higher than 70%, vital features for tissue engineering scaffolds. Moreover, they showed a relatively high swelling of approximately 11 g/g, facilitating oxygen and nutrient exchange. Furthermore, the elastic and compressive moduli of the scaffolds that enhanced significantly upon increasing CNC content were in the range of a few kPa, similar to soft tissues. Finally, no significant cell cytotoxicity was observed against human liver cancer cells (HepG2), highlighting the potential of these developed 3D printed scaffolds for soft tissue engineering applications.


Assuntos
Tinta , Impressão Tridimensional , Celulose/química , Excipientes , Humanos , Hidrogéis/química , Polissacarídeos Bacterianos/química , Engenharia Tecidual , Tecidos Suporte/química
13.
Anal Methods ; 14(19): 1880-1888, 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35506547

RESUMO

Herein, a so-called carbon nanotube (CNT) electrode was printed in on a paper substrate using the handwriting technique and carbon nanotube ink in a marker pen to print the working electrode, graphite pencil to print the counter electrode and graphite/silver nanoparticle (AgNP) ink in a rollerball pen to print the quasi-reference electrode. The carbon nanotube electrode was characterized via scanning electron microscopy. The electrode was optimized based on the type of paper, hydrophobic barrier and number of layers. In summary, the optimized parameters included the use of matte paper with a mineral spirit layer. The number of carbon nanotube layers to achieve the best electrochemical performance was 25. The final graphite electrode was a miniaturized and flexible paper-based electrochemical electrode. To evaluate the electrical properties of the electrodes, the ohmic resistance of each ink was tested using a multimeter and the obtained values were 18.62 kΩ for the CNT ink, 1.53 Ω for the AgNP ink and 3.53 kΩ for the graphite trace. These results indicate the good conductivity of each synthesized ink used in the fabrication of the CNT electrode. Finally, the electrode was used to measure the electrochemical response of different concentrations of K4[Fe(CN)6]. Then, a calibration curve was obtained from the voltammograms and linearity was observed in the range of 0.5-3.5 mM. This suggests that the CNT electrode has the potential to be used as an amperometric electrode.


Assuntos
Grafite , Nanopartículas Metálicas , Nanotubos de Carbono , Eletrodos , Grafite/química , Tinta , Nanotubos de Carbono/química , Prata
14.
Sci Rep ; 12(1): 6828, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35474240

RESUMO

Tyrosinase enzyme was digitally printed on plasma pretreated polyamide-6,6 fabric using several sustainable technologies. Ink containing carboxymethyl cellulose was found to be the most suitable viscosity modifier for this enzyme. Before and after being deposited on the fabric surface, the printed inks retained enzyme activity of 69% and 60%, respectively, compared to activity prior printing process. A good number of the printed enzyme was found to be strongly adsorbed on the fabric surface even after several rinsing cycles due to surface activation by plasma treatment. Rinsed out fabrics retained a maximum activity of 34% resulting from the well-adsorbed enzymes. The activity of tyrosinase on printed fabrics was more stable than ink solution for at least 60 days. Effects of pH, temperature and enzyme kinetics on ink solution and printed fabrics were assessed. Tyrosinase printed synthetic fabrics can be utilized for a range of applications from biosensing and wastewater treatment to cultural heritage works.


Assuntos
Monofenol Mono-Oxigenase , Nylons , Tinta , Têxteis
15.
Sci Rep ; 12(1): 6349, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35428800

RESUMO

The development of 3D printing has recently attracted significant attention on constructing complex three-dimensional physiological microenvironments. However, it is very challenging to provide a bio-ink with cell-harmless and high mold accuracy during extrusion in 3D printing. To overcome this issue, a technique improving the shear-thinning performance of semi-IPN bio-ink, which is universally applicable to all alginate/gelatin-based materials, was developed. Semi-IPN bio-ink prepared by cyclic heating-cooling treatment in this study can reduce the cell damage without sacrificing the accuracy of the scaffolds for its excellent shear-thinning performance. A more than 15% increase in post-printing Cell viability verified the feasibility of the strategy. Moreover, the bio-ink with low molecular weight and wide molecular weight distribution also promoted a uniform cell distribution and cell proliferation in clusters. Overall, this strategy revealed the effects of molecular parameters of semi-IPN bio-inks on printing performance, and the cell activity was studied and it could be widely applicable to construct the simulated extracellular matrix with various bio-inks.


Assuntos
Bioimpressão , Bioimpressão/métodos , Matriz Extracelular , Hidrogéis/farmacologia , Tinta , Peso Molecular , Impressão Tridimensional , Engenharia Tecidual/métodos , Tecidos Suporte
16.
Biofabrication ; 14(3)2022 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-35487196

RESUMO

Three-dimensional (3D) bioprinting is a promising technique for spatially patterning cells and materials into constructs that mimic native tissues and organs. However, a trade-off exists between printability and biological function, where weak materials are typically more suited for 3D cell culture but exhibit poor shape fidelity when printed in air. Recently, a new class of assistive materials has emerged to overcome this limitation and enable fabrication of more complex, biologically relevant geometries, even when using soft materials as bioinks. These materials include support baths, which bioinks are printed into, and sacrificial inks, which are printed themselves and then later removed. Support baths are commonly yield-stress materials that provide physical confinement during the printing process to improve resolution and shape fidelity. Sacrificial inks have primarily been used to create void spaces and pattern perfusable networks, but they can also be combined directly with the bioink to change its mechanical properties for improved printability or increased porosity. Here, we outline the advantages of using such assistive materials in 3D bioprinting, define their material property requirements, and offer case study examples of how these materials are used in practice. Finally, we discuss the remaining challenges and future opportunities in the development of assistive materials that will propel the bioprinting field forward toward creating full-scale, biomimetic tissues and organs.


Assuntos
Bioimpressão , Banhos , Bioimpressão/métodos , Hidrogéis , Tinta , Impressão Tridimensional , Engenharia Tecidual/métodos , Tecidos Suporte
17.
Bioresour Technol ; 353: 127078, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35395367

RESUMO

The present study aimed to enzymatic deinking of waste papers and to valorize the effluent for biobutanol production. Application of fungal enzymatic cocktail (cellulase, amylase, xylanase, pectinase, lipase, and ligninase) on office used paper, newspaper, and ballpen written paper leading to improvement in brightness (84.91, 72.51, 76.69 % ISO), InKd (82.89, 68.95, 76.49%), κ-number (12.9, 13.6, and 13.1), opacity (27.91, 30.07, and 2.85%), tensile strength (49.24, 45.31, and 46.98 Nm/g), respectively and indices were consistent with chemical treated pulps. The quality of effluent generated during enzymatic deinking in respect to BOD and COD level was eco-friendlier than the chemical process. The enzyme-treated effluent was employed as supporting substrate for butanol (18.4 g/l) production by Clostridium acetobutylicum ATCC824. Material balance and life cycle assessment of the whole processes were evaluated to validate its industrial and environmental relevance.


Assuntos
Celulase , Clostridium acetobutylicum , 1-Butanol , Butanóis , Tinta , Papel
18.
Molecules ; 27(7)2022 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-35408547

RESUMO

Silk fibroin, regenerated from Bombyx mori, has shown considerable promise as a printable, aqueous-based ink using a bioinspired salt-bath system in our previous work. Here, we further developed and characterized silk fibroin inks that exhibit concentration-dependent fluorescence spectra at the molecular level. These insights supported extrusion-based 3D printing using concentrated silk fibroin solutions as printing inks. 3D monolithic proteinaceous structures with high aspect ratios were successfully printed using these approaches, including cantilevers only supported at one end. This work provides further insight and broadens the utility of 3D printing with silk fibroin inks for the microfabrication of proteinaceous structures.


Assuntos
Bombyx , Fibroínas , Animais , Fibroínas/química , Tinta , Impressão Tridimensional , Seda/química , Água
19.
J Environ Manage ; 314: 115033, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35427942

RESUMO

Printing ink wastewater from printing facilities is difficult to treat because of its heavy pollutant load (chemical oxygen demand - COD, color and total suspended solids - TSS). In this study undiluted printing ink wastewater with high COD (i.e., 20,000 mgL-1) was treated using a highly efficient, continuous flow electrocoagulation reactor with aluminum electrodes. The parameters investigated were: initial COD concentration (4000, 10,000 and 20,000 mgL-1), current density (21, 42 and 83 mAcm-2), and inlet flow rate (6, 8 and 10 mLmin-1). All parameters showed great efficiency in terms of pollutant removal for diluted printing ink wastewater. For undiluted printing ink wastewater treatment, COD, color, and TSS removal were maximized at 6 mLmin-1 flow rate reaching 82%, 98%, and 85% COD, color, and TSS removal, respectively, by applying the lower tested current density 21 mAcm-2. COD, color and TSS removal increased with increasing current density. For undiluted printing ink wastewater and a flow rate of 8 mLmin-1, COD removal was between 42 and 88%, color reduction between 85 and 99%, and TSS reduction between 83 and 98% when the applied current was increased (from 21 to 83 mAcm-2). Lower pollutant removal was observed at the highest flow rate of 10 mLmin-1 for all current densities tested. Process cost calculations in terms of electrical energy, electrode material consumption and sludge disposal, showed that the use of continuous flow electrocoagulation reactor (with flow rate 6 mLmin-1, and at 21 mAcm-2) is an affordable and effective treatment method for printing ink wastewater streams with very high COD. Sludge characterization showed Al-silicate-rich sludge. Particle sizes increased after treatment and Cu and Ti were detected in the sludge. A post-treatment stage is necessary before discharging effluent into water bodies.


Assuntos
Poluentes Ambientais , Tinta , Águas Residuárias , Eletrocoagulação/métodos , Eletrodos , Esgotos , Eliminação de Resíduos Líquidos/métodos
20.
Biomed Phys Eng Express ; 8(3)2022 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-35290975

RESUMO

Despite advancements in tissue engineering, the methods used to generate three-dimensional (3D)in vitromodels for rapid screening and characterization studies remain time and labor intensive. Bioprinting offers an opportunity to offset these limitations by providing a scalable, high-throughput method with precise control over biomaterial scaffold and cellular deposition. However, the process of formulating bioinks can be complex in terms of balancing the mechanical integrity of a bioscaffold and viability of cells. One key factor, especially in alginate-based bioinks, is the rate of bioscaffold dissolution. It must allow cells to replace the bioscaffold with extracellular matrix (ECM), yet remain durable during extended tissue culture. This study uses a Design of Experiments (DoE) approach to understand the dependencies of multiple variables involved in the formulation and processing of an alginate-based bioink. The focus of the DoE was to understand the effects of hydrogel composition on bioink durability while maintaining cell viability. Three ingredients were varied in all: alginate, nanocellulose, and fibrinogen. Their effects on the bioink were then measured with respect to extrudability, strength, and stiffness as determined by dynamic mechanical analysis (DMA). The DoE demonstrated that mechanical integrity increased with increasing alginate concentration. In contrast, fibrinogen and nanofibril concentration had no statistically significant effect. The optimized ink containing fibroblasts was printable using multiple nozzle sizes while also supporting fibroblast cell viability. DMA characterization further showed that the composition of the cell culture medium did not modulate the degradation rate of the hydrogel. Ultimately, the study outlines a methodology for formulating a bioink that will result in robust bioscaffolds forin vitromodel development.


Assuntos
Bioimpressão , Alginatos , Bioimpressão/métodos , Fibrinogênio , Hidrogéis , Tinta , Impressão Tridimensional
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...