Protein-based animal fibres of commercial importance are frequently exposed to elevated temperatures during processing treatments. Hydrothermal processes cause protein deterioration, impacting negatively on the value ...Protein-based animal fibres of commercial importance are frequently exposed to elevated temperatures during processing treatments. Hydrothermal processes cause protein deterioration, impacting negatively on the value or condition of these materials. This study was designed to investigate hydrothermal damage in wool proteins at the molecular level. The effect of hydrothermal damage on Type I and II intermediate filament proteins (keratins) extracted from wool was characterised using advanced quantitative techniques based on isobaric iTRAQ labelling and mass spectrometry. Many native peptides were observed to be degraded and modified. Amongst these, twenty keratin peptides were observed to consistently degrade during hydrothermal exposure. These peptides acted as molecular markers of damage – specific indicators of the extent of heat-induced protein damage. This technology will be of value in assessing the severity of damage imparted after high temperature exposure of protein-based animal fibres such as wool and cashmere during processes such as dyeing and carbonising, or even after high temperature human hair treatments. The identification of molecular damage markers identified within wool and other materials provides a new route to sensitive and specific evaluation of the effects of protein deterioration. It is anticipated that the utilisation of such markers will facilitate the development of targeted approaches to minimising processing damage to high-value fibres and protein-based biomaterials.展开更多
Controlling fluid flow in capillaric circuits is a key requirement to increase their uptake for assay applications.Capillary action off-valves provide such functionality by pushing an occluding bubble into the channel...Controlling fluid flow in capillaric circuits is a key requirement to increase their uptake for assay applications.Capillary action off-valves provide such functionality by pushing an occluding bubble into the channel using a difference in capillary pressure.Previously,we utilized the binary switching mode of this structure to develop a powerful set of fundamental fluidic valving operations.In this work,we study the transistor-like qualities of the off-valve and provide evidence that these structures are in fact functionally complementary to electronic junction field effect transistors.In view of this,we propose the new term capillaric field effect transistor to describe these types of valves.To support this conclusion,we present a theoretical description,experimental characterization,and practical application of analog flow resistance control.In addition,we demonstrate that the valves can also be reopened.We show modulation of the flow resistance from fully open to pinch-off,determine the flow rate-trigger channel volume relationship and demonstrate that the latter can be modeled using Shockley's equation for electronic transistors.Finally,we provide a first example of how the valves can be opened and closed repeatedly.展开更多
文摘Protein-based animal fibres of commercial importance are frequently exposed to elevated temperatures during processing treatments. Hydrothermal processes cause protein deterioration, impacting negatively on the value or condition of these materials. This study was designed to investigate hydrothermal damage in wool proteins at the molecular level. The effect of hydrothermal damage on Type I and II intermediate filament proteins (keratins) extracted from wool was characterised using advanced quantitative techniques based on isobaric iTRAQ labelling and mass spectrometry. Many native peptides were observed to be degraded and modified. Amongst these, twenty keratin peptides were observed to consistently degrade during hydrothermal exposure. These peptides acted as molecular markers of damage – specific indicators of the extent of heat-induced protein damage. This technology will be of value in assessing the severity of damage imparted after high temperature exposure of protein-based animal fibres such as wool and cashmere during processes such as dyeing and carbonising, or even after high temperature human hair treatments. The identification of molecular damage markers identified within wool and other materials provides a new route to sensitive and specific evaluation of the effects of protein deterioration. It is anticipated that the utilisation of such markers will facilitate the development of targeted approaches to minimising processing damage to high-value fibres and protein-based biomaterials.
基金The authors would like to thank Helen Devereux and Gary Turner of the Nanofabrication Laboratory at the University of Canterbury for technical support.Funding was provided by MBIE Grant UOCX1706.CM.acknowledges support in form of a JSPS Postdoctoral Fellowship for Research in Japan.V.N.acknowledges Rutherford Discovery Fellowship RDF-19-UOC-019for additional funding.
文摘Controlling fluid flow in capillaric circuits is a key requirement to increase their uptake for assay applications.Capillary action off-valves provide such functionality by pushing an occluding bubble into the channel using a difference in capillary pressure.Previously,we utilized the binary switching mode of this structure to develop a powerful set of fundamental fluidic valving operations.In this work,we study the transistor-like qualities of the off-valve and provide evidence that these structures are in fact functionally complementary to electronic junction field effect transistors.In view of this,we propose the new term capillaric field effect transistor to describe these types of valves.To support this conclusion,we present a theoretical description,experimental characterization,and practical application of analog flow resistance control.In addition,we demonstrate that the valves can also be reopened.We show modulation of the flow resistance from fully open to pinch-off,determine the flow rate-trigger channel volume relationship and demonstrate that the latter can be modeled using Shockley's equation for electronic transistors.Finally,we provide a first example of how the valves can be opened and closed repeatedly.
