01701nas a2200157 4500008003900000245009400039210006900133260001600202520112500218653001901343100001501362700001701377700001401394700001801408856011701426 2012 d00aMonitoring cell culture 3D microenvironments: oxygen and pH nano-sensors within hydrogels0 aMonitoring cell culture 3D microenvironments oxygen and pH nanos aRome, Italy3 a

Ratiometric pH and O2 nanosensors were fabricated independently using a fluorophore that produces a signal proportional to the concentration of the analyte of interest, and a second fluorophore that produces a reference signal, insensitive to the analyte of interest. These fluorophores emit at different wavelengths and were either entrapped or covalently bound, within an inert optically transparent polymeric matrix. In this work uniform sized 3D micro-scaled alginate hydrogel constructs of approximately 100-300 $μ$m were fabricated. Through dual incorporation of HepG2 cells and nanosensors within these alginate constructs we aim to have a real-time, non-invasive method to measure microenvironmental pH and O2 content. Ratiometric fluorescent output from the microenvironment is used to monitor O2 concentrations and pH during cell culture. Measurements show that 3D micro-scaled constructs are suitable for cell growth and proliferation. Moreover O2 and pH values within the hydrogel cellularised microspheres are shown to have physiological values that enable the maintenance of the hepatic phenotype

10aBioengineering1 aTirella, A1 aCarroll, L A1 aAylott, J1 aAhluwalia, A. uhttp://95.110.227.16/publications/monitoring-cell-culture-3d-microenvironments-oxygen-and-ph-nano-sensors-within02004nas a2200169 4500008003900000245009200039210006900131260002000200520139200220653001901612653001401631100001501645700001801660700001401678700001701692856012501709 2012 d00a{Monitoring microconstructs: cell and nanosensor encapsulation in alginate micro-beads}0 aMonitoring microconstructs cell and nanosensor encapsulation in  aVienna, Austria3 a

Monitoring and controlling the microenvironment of cell cultures is an ongoing challenge for many researchers. Much research has been conducted characterising individual aspects such as 3D architecture, mechanical properties, biochemicals, etc. The biggest deficits in existing models for monitoring analytes within the cellular environment is the lack of appropriate means for non invasive, real-time and integrated monitoring of the cellular responses. Nanosensors can overcome these issues: they are porous polymeric nanoparticles that are sensitive to a range of analytes including pH and O2. Microfabrication techniques are innovative tools to obtain controlled microstructures with a defined 3D architecture. In this work uniform sized 3D micro-scaled hydrogel constructs of approximately 300-400 um diameter were fabricated. Through dual incorporation of cells and nanosensors within these constructs we aim to have a real-time, non invasive method to measure microenvironmental pH value and O2 content. Ratiometric fluorescent output from the microenvironment is used to monitor O2 and pH during cell culture. Measurements show that 3D micro-scaled constructs are suitable for cell growth and proliferation. Moreover O2 content and pH within hydrogel cellularised microspheres are shown to have physiological values which enable the maintenance of the hepatic phenotype.

10aBioengineering10aNanotools1 aTirella, A1 aAhluwalia, A.1 aAylott, J1 aCarroll, L A uhttp://95.110.227.16/publications/monitoring-microconstructs-cell-and-nanosensor-encapsulation-alginate-micro-beads.html02089nas a2200205 4500008003900000245006300039210006000102260002000162520144900182653001901631653001601650653002401666100001501690700001801705700001701723700001701740700001401757700001601771856009601787 2012 d00aA multi-stimuli environment for cardiac tissue engineering0 amultistimuli environment for cardiac tissue engineering aVienna, Austria3 a

The identification of the ideal cell source to generate cardiac tissue able to integrate into the host myocardium and with the contractile system is crucial for cardiac engineering. Amongst different cell sources so far proposed, human adult Cardiac Progenitor Cells (hCPCs) show the ability to proliferate and differentiate toward cardiac lineages when grown in appropriate microenvironmental conditions. It is widely accepted that conventional 2D cultures may provide a physiological environment for growing cells. For this reason the need to have an engineered microenvironment, matching physiological requirements, is crucial. A 3D context with spatial and time varying distribution of regulatory factors using mechanically matched scaffolds and bioreactors could represent an in vitro cell culture model being able to more closely reflects the in vivo conditions. In the present study, the possibility of using biocompatible and biodegradable scaffolds of collagen based or derivatives hydrogels in combination with Linneg/Sca-1pos hCPCs gathered from human heart biopsies was investigated. Bio-constructs were placed in the low shear, high flow MCmB (MultiCompartment modular Bioreactor) and the combined effects of dynamic culture conditions and 3D scaffolds on cell morphology and differentiation were studied in order to investigate the possibility of fabricating stem cell-derived cardiac patches to replace infarcted tissue.

10aBioengineering10aBioreactors10aDynamic 3D Cultures1 aTirella, A1 aAhluwalia, A.1 aDi Nardo, P.1 aGaudiello, E1 aGiusti, S1 aPagliari, F uhttp://95.110.227.16/publications/multi-stimuli-environment-cardiac-tissue-engineering.html00666nas a2200169 4500008003900000245006500039210006500104260002400169520010200193653001900295100001500314700001500329700001900344700001400363700001800377856010100395 2011 d00aModelling and realisation of smart graded hydrogel scaffolds0 aModelling and realisation of smart graded hydrogel scaffolds aMontpellier, France3 a

European Congress and Exhibition on Advanced Materials and Processes - Poster F12-P-2-08

10aBioengineering1 aTirella, A1 aMattei, G.1 aMontemurro, F.1 aVozzi, G.1 aAhluwalia, A. uhttp://95.110.227.16/publications/modelling-and-realisation-smart-graded-hydrogel-scaffolds.html00561nas a2200145 4500008004100000245008600041210007000127300000800197653001900205100001400224700001500238700001800253700001400271856013000285 2008 eng d00aMicrofabbricazione di scaffold in alginato con proprietà  meccaniche modulabili0 aMicrofabbricazione di scaffold in alginato con proprietà meccani a–10aBioengineering1 aOrsini, A1 aTirella, A1 aAhluwalia, A.1 aVozzi, G. uhttp://95.110.227.16/publications/microfabbricazione-di-scaffold-alginato-con-propriet%C3%A0%C2%A0-meccaniche-modulabili.html00535nas a2200133 4500008004100000245009200041210006900133260001600202300001200218653001900230100001500249700001400264856012300278 2008 eng d00aMicrofabrication of Hydrogels scaffolds including cells and mechanical characterization0 aMicrofabrication of Hydrogels scaffolds including cells and mech aPisa, Italy a367-36810aBioengineering1 aTirella, A1 aVozzi, G. uhttp://95.110.227.16/publications/microfabrication-hydrogels-scaffolds-including-cells-and-mechanical-characterization00538nas a2200169 4500008003900000245005500039210005500094260002000149300000800169520002000177653001900197100001500216700001500231700001400246700001800260856009000278 2008 d00aMicrofluidic Gradient Maker for Pattern Generation0 aMicrofluidic Gradient Maker for Pattern Generation aPorto, Portugal a8793 a

poster

10aBioengineering1 aTirella, A1 aMazzei, D.1 aVozzi, G.1 aAhluwalia, A. uhttp://95.110.227.16/publications/microfluidic-gradient-maker-pattern-generation.html01872nas a2200181 4500008004100000022001400041245008400055210006900139300001400208490000700222520133400229653001901563100001501582700001401597700001301611700001801624856004801642 2008 eng d a0887-233300aA microfluidic gradient maker for toxicity testing of bupivacaine and lidocaine0 amicrofluidic gradient maker for toxicity testing of bupivacaine  a1957–640 v223 a

A great deal of effort is being dedicated to the development of new devices able to conduct effective in vitro toxicology analyses. This paper describes the use of a microfluidic gradient maker for the toxicological analysis of two conventional local anesthetics, bupivacaine and lidocaine on cell cultures. The microfluidic device was designed and simulated using COMSOL Multiphysics and the concentration gradient in the microfluidic network was analysed through a fluidodynamic and diffusive study. Subsequently the device was fabricated with soft lithography, casting PDMS in a master to obtain channels about 250 microm deep. Both drugs were tested on C2C12 myoblasts and an analysis was performed using propidium iodide staining followed by an imaging processing routine to obtain quantitative dose-response profiles in the gradient maker. The system was critically compared with microwell-based toxicity testing. The results show that the GM is a more sensitive method for detection of cell toxicity, and compared with testing of drug toxicity using microwells with individual cell cultures, allows one shot testing with a single cell culture exposed to a large number of concentrations. However, the flow rates required to obtain a suitable concentration range across the device may damage shear sensitive cells.

10aBioengineering1 aTirella, A1 aMarano, M1 aVozzi, F1 aAhluwalia, A. uhttp://www.ncbi.nlm.nih.gov/pubmed/18940244