Reconfigurable Implication and Inhibition Boolean logic gates based on NAD+-dependent enzymes: Application to signal-controlled biofuel cells and molecule release

AbstractThe Implication and Inhibition Boolean logic gates were realized using NAD+/NADH‐dependent dehydrogenases combined with hexokinase competing for biomolecule input signals. Both logic gates operated with the same enzyme composition and their reconfiguration was achieved simply by redefining the input signals. The output signals produced by the logic gates were analyzed optically and electrochemically, particularly using enzyme‐modified electrodes. The logically processed input signals were used to switch operation of a biofuel cell and activate a molecule release process

Molecular Logic: From Single Logic Gates to Sophisticated Logic Circuits, from Fundamental Science to Practical Applications

[No abstract available

Integration of biomolecular logic principles with electronic transducers on a chip

Boolean operations applied in biology and integrated with electronic transducers allow the development of a new class of digital biosensors for the detection of multiple input signals simultaneously and in real-time. With the help of Boolean functions (AND, OR, etc.), an electrical output signal will be directly delivered, representing a ”1” or “0” binary notation, corresponding to a “true” or “false” statement, respectively. Such digital biosensors have the future potential to create medical devices and systems for intelligent or smart diagnostics. The present thesis describes the realization of different enzyme-based biomolecular logic gates combined with electronic transducers for the possible application in medicine or food industry. In a first concept, a so called BioLogicChip is developed combining a “sense-act-treat” function integrated on one chip. The present system exemplarily mimics an “artificial pancreas” designed as a closed-loop drug-release system. A glucose sensor is constructed as enzyme-based AND logic gate, a temperature-depending hydrogel imitates the actuator function switching ON and OFF with its shrinking or swelling property, and an additional insulin sensor is developed to monitor and control the release of the drug (here: insulin) from the actuator. In this study, the results of the individual components such as the amperometric glucose sensor, the temperature-dependent hydrogel and the amperometric insulin sensor are presented, which are necessary to create such BioLogicChip. Moreover, a digital adrenaline biosensor is developed to proof the catheter position during adrenal vein sampling. The sensor consists of an oxygen electrode modified by a bi-enzyme system with the enzymes laccase and pyrroloquinoline quinone-dependent glucose dehydrogenase (PQQ-GDH) to realize substrate-recycling principle to detect low adrenaline concentrations (in the nanomolar concentration range). The sensor`s behavior at different pH values and at different temperatures is studied. Measurements in Ringer`s solution are performed. In addition, the sensitivity of the biosensor to other catecholamines such as noradrenaline, dopamine and dobutamine is investigated. Furthermore, the adrenaline biosensor is successfully examined in human blood plasma. Finally, “proof-of-principle” experiments have been performed by combining the adrenaline biosensor with Boolean operations to get a rapid qualitative statement of the presence or absence of adrenaline, thus validating the correct position of the catheter in a YES/NO form. This adrenaline biosensor is further miniaturized as a thin-film platinum adrenaline biosensor. Here, the bioelectrocatalytical measurement principle is applied by immobilization of the enzyme PQQ-GDH to detect adrenaline in the nanomolar concentration range, too. The measurement conditions such as pH value, glucose concentration in the analyte solution and temperature are optimized with regard to a high sensitivity and low detection limit. Also, this sensor has been verified towards other catecholamines (noradrenaline, dopamine and dobutamine). The platinum thin-film adrenaline biosensor is successfully applied in blood plasma for the detection of different spiked adrenaline concentrations. Furthermore, the developed adrenalin biosensor is able to detect the concentration difference between adrenal blood and peripheral blood. In contrast to the above-mentioned amperometric biosensor examples for biomolecular gates, also a field-effect-based platform is given attention in this thesis. The field-effect electrolyte-insulator-semiconductor (EIS) sensor consists of a layer structure of Al/p-Si/SiO2/Ta2O5 and is used to create an acetoin biosensor for the first time to control different fermentation processes. The sensor chip is modified by the enzyme acetoin reductase from B. clausii DSM 8716T for the catalytical reaction of (R)-acetoin to (R,R)-butanediol and meso-butanediol, respectively, in the presence of NADH. The linear measurement range, the optimal immobilization strategy (cross-linking by using glutaraldehyde and adsorptive binding) as well as the optimal working pH value and long-term stability are investigated by means of constant-capacitance measurements. Finally, the acetoin sensor was successfully applied in wine probes to detect different spiked acetoin concentrations. The sensor shows opportunities to be further developed as digital acetoin biosensor

2009 Major Sponsored Programs and Faculty Awards for Research and Creative Activity

From discoveries in nanoscience, nutrigenomics and software engineering to innovative initiatives in math achievement, child welfare, water and climate change, UNL faculty are engaged in meeting the challenges of a changing world. This eighth annual “Major Sponsored Programs and Faculty Awards for Research and Creative Activity” booklet highlights the successes of University of Nebraska–Lincoln faculty during 2009. It lists the funding sources, projects and investigators on major grants and sponsored program awards received during the year; published books and scholarship; fellowships and other recognitions; start-ups and intellectual property licenses; and performances and exhibitions in the fine and performing arts. This impressive list grows each year and I am pleased to present evidence of our faculty’s accomplishments. Large grants in fields ranging from rural and math education to water and renewable energy to virology, redox biology and nanomaterials enable UNL faculty to address important challenges facing Nebraska, our nation and the world. Our external research funding reflects their achievements, reaching a new record total of $122 million in fiscal year 2009, marking a 13 percent increase over last year. We are harnessing this momentum to advance new initiatives with an innovative perspective and research that responds to a changing world. We are reaching beyond our institutional, state and national borders to build partnerships that seek solutions to global challenges, provide our students with an interdisciplinary, international perspective, and enhance our state’s economy. As you read the accomplishments in this booklet, I invite you to imagine how the innovative and collaborative research, scholarship and creative activity of our faculty is changing our world and meeting the complex global challenges that lie before us

2009 Major Sponsored Programs and Faculty Awards for Research and Creative Activity

From discoveries in nanoscience, nutrigenomics and software engineering to innovative initiatives in math achievement, child welfare, water and climate change, UNL faculty are engaged in meeting the challenges of a changing world. This eighth annual “Major Sponsored Programs and Faculty Awards for Research and Creative Activity” booklet highlights the successes of University of Nebraska–Lincoln faculty during 2009. It lists the funding sources, projects and investigators on major grants and sponsored program awards received during the year; published books and scholarship; fellowships and other recognitions; start-ups and intellectual property licenses; and performances and exhibitions in the fine and performing arts. This impressive list grows each year and I am pleased to present evidence of our faculty’s accomplishments. Large grants in fields ranging from rural and math education to water and renewable energy to virology, redox biology and nanomaterials enable UNL faculty to address important challenges facing Nebraska, our nation and the world. Our external research funding reflects their achievements, reaching a new record total of $122 million in fiscal year 2009, marking a 13 percent increase over last year. We are harnessing this momentum to advance new initiatives with an innovative perspective and research that responds to a changing world. We are reaching beyond our institutional, state and national borders to build partnerships that seek solutions to global challenges, provide our students with an interdisciplinary, international perspective, and enhance our state’s economy. As you read the accomplishments in this booklet, I invite you to imagine how the innovative and collaborative research, scholarship and creative activity of our faculty is changing our world and meeting the complex global challenges that lie before us