Cyborg cells: Functionalisation of living cells with polymers and nanomaterials

Living cells interfaced with a range of polyelectrolyte coatings, magnetic and noble metal nanoparticles, hard mineral shells and other complex nanomaterials can perform functions often completely different from their original specialisation. Such "cyborg cells" are already finding a range of novel applications in areas like whole cell biosensors, bioelectronics, toxicity microscreening, tissue engineering, cell implant protection and bioanalytical chemistry. In this tutorial review, we describe the development of novel methods for functionalisation of cells with polymers and nanoparticles and comment on future advances in this technology in the light of other literature approaches. We review recent studies on the cell viability and function upon direct deposition of nanoparticles, coating with polyelectrolytes, polymer assisted assembly of nanomaterials and hard shells on the cell surface. The cell toxicity issues are considered for many practical applications in terms of possible adverse effects of the deposited polymers, polyelectrolytes and nanoparticles on the cell surface. © 2012 The Royal Society of Chemistry

Silver nanoparticle-coated "cyborg" microorganisms: Rapid assembly of polymer-stabilised nanoparticles on microbial cells

© The Royal Society of Chemistry. Fabrication of "cyborg" cells (biological cells with surfaces functionalised using a variety of nanomaterials) has become a fascinating area in cell surface engineering. Here we report a simple procedure for fabrication of polycation-stabilised 50 nm silver nanoparticles and application of these nanoparticles for fabrication of viable "cyborg" microbial cells (yeast and bacteria). Cationic polymer-stabilised nanoparticles electrostatically adhere to microbial cells producing an even monolayer on the cell walls, as demonstrated using enhanced dark-field microscopy, atomic force microscopy and microelectrophoresis. Our procedure is exceptionally fast, being completed within 20 min after introduction of cells into nanoparticle aqueous suspensions. Polymer-stabilised silver nanoparticles are highly biocompatible, with viability rates reaching 97%. We utilised "cyborg" cells built using bacteria and silver nanoparticles to deliver nanoparticles into C. elegans microworms. We believe that the technique described here will find numerous applications in cell surface engineering. This journal i

Functional artificial free-standing yeast biofilms

Here we report fabrication of artificial free-standing yeast biofilms built using sacrificial calcium carbonate-coated templates and layer-by-layer assembly of extracellular matrix-mimicking polyelectrolyte multilayers. The free-standing biofilms are freely floating multilayered films of oppositely charged polyelectrolytes and live cells incorporated in the polyelectrolyte layers. Such biofilms were initially formed on glass substrates of circular and ribbon-like shapes coated with thin layers of calcium carbonate microparticles. The templates were then coated with cationic and anionic polyelectrolytes to produce a supporting multilayered thin film. Then the yeast alone or mixed with various micro- and nanoparticle inclusions was deposited onto the multilayer composite films and further coated with outer polyelectrolyte multilayers. To detach the biofilms from the glass substrates the calcium carbonate layer was chemically dissolved yielding free-standing composite biofilms. These artificial biofilms to a certain degree mimic the primitive multicellular and colonial species. We have demonstrated the added functionality of the free-standing artificial biofilms containing magnetic, latex and silver micro- and nanoparticles. We have also developed "symbiotic" multicellular biofilms containing yeast and bacteria. This approach for fabrication of free-standing artificial biofilms can be potentially helpful in development of artificial colonial microorganisms composed of several different unicellular species and an important tool for growing cell cultures free of supporting substrates. © 2011 Elsevier B.V

Nanomodified Bacteria Alcanivorax Borkumensis as an Indicator of Carbohydrates in Sea Water

The work was supported by the Russian Foundation for Basic Research (grant № 18-34-00778), by Program of Competitive Growth of KFU and funded by Russian presidential grant (MK-4498.2018.4)

Elucidation of a masked repeating structure of the O-specific polysaccharide of the halotolerant soil bacteria Azospirillum halopraeferens Au4

Abstract An O-specific polysaccharide was obtained by mild acid hydrolysis of the lipopolysaccharide isolated by the phenol-water extraction from the halotolerant soil bacteria Azospirillum halopraeferens type strain Au4. The polysaccharide was studied by sugar and methylation analyses, selective cleavages by Smith degradation and solvolysis with trifluoroacetic acid, one-and two-dimensional 1 H and 13 C NMR spectroscopy. The following masked repeating structure of the O-specific polysaccharide was established: →3)- where non-stoichiometric substituents, an O-methyl group (~45%) and a side-chain glucose residue (~65%), are shown in italics. 63

Pengaruh Temperatur dan Media Pendingin pada Proses Heat Treatment Baja AISI 1045 terhadap Kekerasan dan Laju Korosi

Baja karbon adalah logam yang paling banyak digunakan pada dunia industri dan untuk memenuhi kebutuhan hidup manusia. Salah satu jenis baja yang paling banyak digunakan adalah baja AISI 1045 atau baja karbon sedang. Baja AISI 1045 dibuat dan dibentuk komponen, sparepart, atau alat-alat sesuai dengan kebutuhan di dunia industri, maka muncul upaya untuk memperbaiki sifat mekanik dan ketahanan terhadap korosi. Tujuan dari penelitian ini adalah untuk mengetahui pengaruh temperatur dan media pendingin pada proses heat treatment terhadap nilai kekerasan baja AISI 1045, mengetahui pengaruh temperatur dan media pendingin pada proses heat treatment terhadap laju korosi baja AISI 1045. Pada penelitian ini spesimen dipanaskan menggunakan tungku pemanas dengan temperatur7500C, 8500C, dan 9500C dengan holding time selama 30 menit. Kemudian masing-masing material dilakukan quenching pada media air mineral dan oli SAE 10w-40. Selanjutnya material dilakukan uji kekerasan dan uji korosi. Hasilnya material mengalami perubahan kekerasan dan laju korosi. Nilai kekerasan tertinggi terjadi pada media pendingin air mineral yaitu 58,2 HRC pada variasi temperatur 8500C dan nilai kekerasan tertinggi media pendingin oli adalah 33,4 HRC pada variasi temperatur 9500C. Laju korosi tertinggi media pendingin air mineral adalah 3,998 ipy pada variasi temperatur 9500C, dan 4,086 ipy pada media pendingin oli dengan variasi temperatur 9500C.Kata kunci: Temperatur, media pendingin, heat treatment, kekerasan, dan laju korosi

Halloysites Stabilized Emulsions for Hydroformylation of Long Chain Olefins

© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, WeinheimHalloysites as tubular alumosilicates are introduced as inexpensive natural nanoparticles to form and stabilize oil–water emulsions. This stabilized emulsion is shown to enable efficient interfacial catalytic reactions. Yield, selectivity, and product separation can be tremendously enhanced, e.g., for the hydroformylation reaction of dodecene to tridecanal. In perspective, this type of formulation may be used for oil spill dispersions. The key elements of the described formulations are clay nanotubes (halloysites) which are highly anisometric, can be filled by helper molecules, and are abundantly available in thousands of tons, making this technology scalable for industrial applications

Характеристика лямблиоза и энтеробиоза у детей Астраханской области

Purpose: assessment of the clinical and epidemiological situation of current invasions in children of the Astrakhan region. 315 outpatient cards of children were analyzed in 2016.The diagnosis of Giardiasis was made to 151 children, the diagnosis of Enterobiasis — 164. The age of all observed children ranged from 9 months to 17 years. The largest part was made up of children aged 3 to 14 years of age — 80.3%, among them enterobiasis was identified — in 46.7%, giardiasis — in 33.6% of cases. Most of the children  — 90.5% were from organized groups (they attended preschool institutions or school). The reasons for the examination of all children were varied. Some children — 63.5% went to the doctor with complaints  or clinical symptoms. Another part of the children — 33% of the diagnosis was made as a result of preventive examinations.In most cases — 78.7% various bad habits were identified. Thus, geophagy (the habit of eating the earth) was noted in 33.3% of children, and onigophagy (the habit of biting the nails) in 24.8%. In 21.3% of cases, bad habits were absent. Contact with pets was established in 22.9% of children. According to the ultrasound, most children with giardiasis (83.8%) had pathology (reactive changes of the pancreas, liver, gallbladder dyskinesia, etc.)In case of giardiasis niferator, albendazole was administered. In case of enterobiasis albendazole, pyrantel, and mebendazole were administered in age dosages. After antiparasitic treatment, in 91.4% of cases, the clinical symptoms of the disease completely disappeared, with giardiasis — in 85.4%, with enterobiasis — in 97% of cases.In 1.3% of children with giardiasis, after several courses of antiparasitic drugs, Giardia was found in feces in the absence of complaints and clinical symptoms, indicating a possible Giardia carrier parasite in children.С целью оценки клинико-эпидемиологической ситуации по актуальным инвазиям у детей Астраханской области было проанализировано 315 амбулаторных карт детей, обратившихся в 2016  г. Диагноз Лямблиоз был поставлен 151 ребенку, диагноз Энтеробиоз — 164.Возраст всех наблюдаемых детей составлял от 9 месяцев до 17 лет. Наибольшую часть составили дети в возрасте от 3 до 14 лет жизни — 80,3%, среди них энтеробиоз был выявлен в 46,7%, лямблиоз — в 33,6% случаев. Большинство детей — 90,5% были из организованных коллективов (посещали  детские дошкольные учреждения или школу). Причины обследования всех детей были разнообразными.  Часть  детей  — 63,5% обратились к специалисту в связи с наличием у них тех или иных клинических симптомов и жалоб. Другой части  детей  — 33% диагноз был выставлен в результате профилактических осмотров.В большинстве  случаев — 78,7% были выявлены различные вредные привычки. Так, геофагия (привычка есть землю) отмечалась у 33,3% детей, а онигофагия (привычка грызть ногти) — у 24,8%. В 21,3% случаев вредные привычки отсутствовали. Котакт с домашними животными был установлен  у 22,9% детей. По данным УЗИ, у большинства детей с лямблиозом (83,8%) отмечалась патология (реактивные изменения поджелудочной железы, печени, дискинезия желчного пузыря и др.).В качестве антипаразитарной  терапии при лямблиозе назначался нифуратель, альбендазол, при энтеробиозе — альбендазол, пирантел и мебендазол в возрастных дозировках. После лечения в 91,4% случаев клинические симптомы заболевания полностью исчезли, при лямблиозе — в 85,4%, при энтеробиозе — в 97% случаев.У 1,3% детей с лямблиозом после нескольких курсов антипаразитарными препаратами обнаруживались лямблии в фекалиях при отсутствии жалоб и клинических симптомов, что свидетельствует о возможном паразитоносительстве лямблий у детей