Search results for "Printing"

Criminal DNA databases: the European situation

2001

In the last 5 years, a number of European countries have successfully introduced national databases holding the DNA profiles from suspected and convicted criminal offenders as well as from biological stain materials from unsolved crime cases. At present, DNA databases are fully or partially in operation in the UK, The Netherlands, Austria, Germany, Finland, Norway, Denmark, Switzerland and Sweden. Furthermore, in the other European countries, specific legislation will be enacted soon, or the introduction of such databases is being discussed to initiate a legislative process. Numerous differences exist regarding the criteria for a criminal offender to be included in the database, the storage…

Ink-Jet Printing for drug srreening on microarrays: from covalent approaches to in-liquid-droplets assays

2012

Drug screening is the complex process of retrieving chemical compounds able to modulate the activity of biological targets which are of interest for certain diseases. Conventional miniaturized drug screening technologies are based on robotic dispensers coupled with microwell arrays. However these devices require time and reagent consuming (micro-, nanoliter scale) instrumental tools, liquid handling robotics and complex detectors. Here we show a low-cost and efficient drug screening methodology based on inkjet printing for delivering molecular systems in picoliter volumes coupled with easily-implemented detection tools for probing target-drug interaction. We firstly show up a screening plat…

Patterns of glucose oxidase by inkjet printing for biosensing applications,

2008

Luminometric Sub-nanoliter Droplet-to-droplet Arrays (LUMDA-chip) for Drug Screening on Phase I Metabolism Enzymes

2013

Here we show the fabrication of the Luminometric Sub-nanoliter Droplet-to-droplet Array (LUMDA chip) by inkjet printing. The chip is easy to be implemented and allows for amultiplexed multi-step biochemical assay in sub-nanoliter liquid spots. This concept is here applied to the integral membrane enzyme CYP3A4, i.e. themost relevant enzymatic target for phase I drug metabolism, and to some structurally-related inhibitors.

Printing Biology for Advanced Synthetic Biosystem

2019

Printing technologies represent a powerful tool for the direct micro- and nano- fabrication of biomolecular structures at the interface between life and materials sciences (Arrabito et al., 2012). Their continuous development over the last years has permitted the onset of man-made biosystems with customizable dimensions (from the micron-scale down to the nanometer scale), composition (organic molecules, DNA, proteins, phospholipids), and relevant functions (molecular interactions, drug screening, cellular biointerfaces, cell-like compartments). In this work, we show the possibility to leverage the fabrication of a wide class of solid-supported or liquid-liquid based synthetic compartments b…

Micro and Nano patterns for Biosensing: from enzymatic assays to single cells interaction arrays

2012

In this thesis work, solution dispensing techniques have been employed for the realization of complex biological arrays. Inkjet printing techniques were employed for the generation of drug screening platforms. This approach was initially proved with a model enzyme system like Glucose Oxidase substrate covalently linked to a functionalized silicon oxide support. On this support an enzymatic substrate (D-glucose)/inhibitor (D-glucal) couple was accurately dispensed. A simple optical detection method was used to prove the screening capability of the microarray with the possibility to assay with high reproducibility at the single spot level. Afterwards, this methodology has been extended to CYP…

Metodologie da stampa a getto d'inchiostro per la fabbricazione di substrati SERS

2019

Uno degli argomenti di maggiore interesse della Surface-enhanced Raman spectroscopy (SERS) è il controllo del posizionamento su superficie degli “hot spots” – le zone interstiziali fra aggregati di particelle metalliche che producono un aumento locale del segnale Raman. I substrati SERS consistono tipicamente in una matrice di hot-spots ad alta densità sui quali volumi macroscopici (>1 µL) di molecole di analita sono disperse. Questo approccio porta ad una alta invasività ed una distribuzione non uniforme dell’analita a causa dei flussi capillari. In questo lavoro, viene sviluppata una nuova piattaforma SERS realizzata da stampa a getto d’inchiostro2 in cui una miscela di un analita SERS…

High-throughput screening at the picoliter scale by combining Dip Pen Lithography with Inkjet printing

Drug screening is a complex, expensive and time consuming field consisting of diseasebased target identification in conjunction with high-throughput screening of chemical and natural product libraries. Conventional drug screening technology is usually time and reagent consuming (micro-, nanoliter scale) and is based on complex liquid handling robotics. In this work, we show a low-cost and miniaturized drug screening methodology based on direct bio-printing methodologies like Inkjet Printing and Dip Pen Lithography. We show the possibility to precisely deliver femtoliter scale droplets of protein targets by Dip Pen Lithography by finely tuning deposition parameters. This allows obtaining mic…

Mechanisms involved in the transmission of epigenetic deregulation : analyses of transmission in human sperm

2018

The notion that environmental exposure can be memorized and promote epimutation (defined as defects on DNA methylation) raises the question of possible epigenetic transgenerational transmission in humans. To address whether an epimutation could be transmitted in humans, we pursued two axes. First, the evaluation of intergenerational transmission in the family of a Silver-Russell patient has shown, for the first time, the efficiency of epigenetic reprogramming in humans, specifically on imprinted regions. Indeed, no imprinted defect on causal H19/IGF2 locus was detected in the patient’s spermatozoa or in the DNA of his daughter. The second axis was to assess the presence of sperm epimutation…

Hybridization in Capparis spinosa L.: Molecular and morphological evidence from a Mediterranean island complex

2014

Inter-Simple Sequence Repeat (ISSR) molecular markers and morphological analysis were used in order to characterize wild populations and cultivated forms of orphan crop species Capparis spinosa L. in a Mediterranean island complex. Nineteen wild populations belonging to two different subspecies, C. spinosa subsp. spinosa and subsp. rupestris, were sampled in different environments in Sicily and the surrounding islets Lampedusa, Pantelleria and Salina. Different biotypes cultivated in Pantelleria and Salina were analyzed. Six ISSR primers were selected for genetic characterization, and all clear and reproducible bands were scored and analyzed. Among the 47 ISSR bands obtained, 97.5% were pol…