Month: May 2018

Hot off the press! Published paper on The Chemical Record

Congratulations to the authors Martí Gich, Anna Roig (N&N group), Pengfei Niu (former member of the N&N group) and César Fernández‐Sánchez (N&N collaborator form the Barcelona Institute of Microelectronics) for their published paper “Metal Nanoparticle Carbon Gel Composites in Environment in Water Sensing Applications”. The manuscript was published in the journal Chemical Record in a special issue dedicated to Prof. Ruiz-Hitzky.

 

Abstract: The synthesis of organic‐inorganic nanocomposites that can interact with different environmental pollutants and can be mass‐produced are very promising materials for the fabrication of chemical sensor devices. Among them, metal (or metal oxide) nanoparticles doped conductive porous carbon composites can be readily applied to the production of electrochemical sensors and show enhanced sensitivity for the measurement of water pollutants, thanks to the abundant accessible and functional sites provided by the interconnected porosity and the metallic nanoparticles, respectively. In this personal account, an overview of several synthesis routes of porous carbon composites containing metallic nanoparticles is given, paying special attention to those based on sol‐gel techniques. These are very powerful to synthesize hybrid porous materials that can be easily processed into powders and thin films, so that they can be implemented in electrode fabrication processes based on screen‐printing and lithography techniques, respectively. We emphasize the sol‐gel routes developed in our group for the synthesis of bismuth or gold nanoparticle doped porous carbon composites applied to fabricate electrochemical sensors that can be scaled down to produce miniaturized on‐chip sensing devices for the sensitive detection of heavy metal pollutants in water. The trend towards the miniaturization of electrochemical sensors to be readily employed as analytical tools in environmental monitoring follow the market requirements of rapid and accurate on‐site analysis, small sample consumption and waste production, as well as potential for continuous or semi‐continuous in‐situ determination of a wide variety of target analytes.

ICMAB party 2018

17th May, 2018

Every spring, ICMAB celebrates its anniversary with a party for all the members of the institute. This year the N&N group members participated in many of the purposed activities: orienteering race (second place for the team of Martí, Jan and Miquel), tango lessons, custumes contest (second prize for the NN group), the concert by the ICMAB-choir (Anna Roig) and the ping-pong tournament where Martí Gich was a finalist!

We all enjoyed the diverse and original activities and thank all the organizers.

The orienteering race brought us to many unknown corners of the UAB-campus
The concert
Second prize

New paper from the group!

Congratulations to Anna LaromaineAnna Roig and their collaborators from the Karlsruhe Institute of Technology Tina Tronser (first author) and Pavel A. Levkin for their new paper: Bacterial Cellulose Promotes Long-Term Stemness of mESC! This manuscript was published on ACS Applied Materials and Interfaces the 20th of April 2018.  

 

Abstract: Stem cells possess unique properties, such as the ability to self-renew and the potential to differentiate into an organism’s various cell types. These make them highly valuable in regenerative medicine and tissue engineering. Their properties are precisely regulated in vivo through complex mechanisms that include multiple cues arising from the cell interaction with the surrounding extracellular matrix, neighboring cells, and soluble factors. Although much research effort has focused on developing systems and materials that mimic this complex microenvironment, the controlled regulation of differentiation and maintenance of stemness in vitro remains elusive. In this work, we demonstrate, for the first time, that the nanofibrous bacterial cellulose (BC) membrane derived from Komagataeibacter xylinus can inhibit the differentiation of mouse embryonic stem cells (mESC) under long-term conditions (17 days), improving their mouse embryonic fibroblast (MEF)-free cultivation in comparison to the MEF-supported conventional culture. The maintained cells’ pluripotency was confirmed by the mESCs’ ability to differentiate into the three germ layers (endo-, meso-, and ectoderm) after having been cultured on the BC membrane for 6 days. In addition, the culturing of mESCs on flexible, free-standing BC membranes enables the quick and facile manipulation and transfer of stem cells between culture dishes, both of which significantly facilitate the use of stem cells in routine culture and various applications. To investigate the influence of the structural and topographical properties of the cellulose on stem cell differentiation, we used the cellulose membranes differing in membrane thickness, porosity, and surface roughness. This work identifies bacterial cellulose as a novel convenient and flexible membrane material enabling long-term maintenance of mESCs’ stemness and significantly facilitating the handling and culturing of stem cells.

 

Lab cleaning, pizzas and ping-pong!

Every three months, the N&N group organizes a lab cleaning day, which is normally accompanied by a pizza lunch, but today there was a novelty: The first N&N Ping-Pong tournament! Congratulations to Anna Roig for being the winner and special thanks to Miquel and Jan for the organization tasks. 

 

Congratulations to Nerea Murillo for the Extraordinay PhD Award!

We congratulate Nerea Murillo and her supervisors Anna Roig and Concepció Domingo for the Extraordinary PhD Award (Premi Extraordinari de Doctorat) for her thesis entitled “MULTIFUNCTIONAL SILICA-BASED NANOPARTICLES FOR BIOMEDICAL APPLICATIONS“. Nerea defended her PhD thesis at ICMAB on 2014, her project aimed to fabricate hybrid (organic-inorganic) complex materials as drug carriers  using supercritical fluids. The award ceremony will take place next Friday 18th May at the Auditori de Lletres i de Psicologia of the Autonomous Univeristy of Barcelona.

Graphical summary of Nerea’s work

Hot of the press! New article about Bacterial Cellulose

Congratulations to the authors: Anna Laromaine, Tina Tronser, Ivana Pini, Sebastià Parets, Pavel A. Levkin and Anna Roig for their new publication on Soft Matter. The paper entitled “Free-standing three-dimensional hollow bacterial cellulose structures with controlled geometry via patterned superhydrophobic–hydrophilic surfaces” was published on the 17th of April 2018. 

Abstract
Bacteria can produce cellulose, one of the most abundant biopolymer on earth, and it emerges as an interesting candidate to fabricate advanced materials. Cellulose produced by Komagataeibacter Xylinus a bacterial strain, is a pure water insoluble biopolymer, without hemicelluloses or lignin. Bacterial cellulose (BC) exhibits a nanofibrous porous network microstructure with high strength, low density and high biocompatibility and it has been proposed as a cell scaffold and wound healing material. The formation of three dimensional (3D) cellulose self-standing structures is not simple. It either involves complex multi-step synthetic procedures or uses chemical methods to dissolve the cellulose and remold it. Here we present an in situ single-step method to produce self-standing 3D-BC structures with controllable wall thickness, size and geometry in a reproducible manner. Parameters such as hydrophobicity of the surfaces, volume of the inoculum and time of culture define the resulting 3D-BC structures. Hollow spheres and convex domes can be easily obtained by changing the surface wettability where the BC grows. The potential of these structures as a 3D cell scaffold is exemplified supporting the growth of mouse embryonic stem cells within a hollow spherical BC structure, indicating its biocompatibility and future prospective.