Advances in miniaturization

Thanks to advances in miniaturization and developments in sensors and measurement technologies, it is already possible to collect a considerable amount of health-related information from wearable or embedded devices, and numerous new devices are also in the pipeline (Table 32.1). Some of these devices function on a constant basis, whereas others take intermittent mea-... 

A number of developments have increased the importance of capillary electrophoretic methods relative to pumped column methods in analysis. Interactions of analytes with the capillary wall are better understood, inspiring the development of means to minimize wall effects. Capillary electrophoresis (CE) has been standardized to the point of being useful as a routine technique. Incremental improvements in column coating techniques, buffer preparation, and injection techniques, combined with substantive advances in miniaturization and detection have potentiated rugged operation and high capacity massive parallelism in analysis. 

Extensive review literature exists in the area of biological fuel cells. Notably, Palmore and Whitesides summarized biological fuel cell concepts and performance up to 1992." More recently, Katz and Willner discussed recent progress in novel electrode chemistries for both microbial and enzymatic fuel cells,and Heller reviewed advances in miniature cells.This article does not duplicate these valuable contributions. Instead, we focus on the strengths and weak-... 

Controlled release can be achieved using infusion devices in hospital and chn-ical settings. Advances in miniaturization of these devices is beginning to provide portability. Ftowever, these devices are not ideal for most applications due to their cost and complex training requirements. 

The previously mentioned drawback of biosensing devices, i.e., the possibility to measure just one metabolite at a time, is nowadays partially overcome through the recent advances in miniaturization and the development of arrays of sensors. Each of the sensors constituting the array can consist in a different biosensor, allowing multi-analyte determinations. In some cases, if the array is located in a flow cell, it can be coupled to microdialysis sampling. Examples have been presented by several authors, even if the proposed... 

Future applications of CE to PCR product analysis will arise from improvements in CE instrumentation. Advances in miniaturization of CE devices by producing glass chips with etched channels of <1 cm in length... 

In the late 1990s (1998-1999), the CPAC Summer Institute focused on the advances in miniaturization that were influencing areas that are related to micro-analytical and micro-instrumentation developments. These included presentations and discussions on developments in micro-unit operations (microfluidics, micropumps, microfilters, etc.). A concern that continues to arise in these discussions was the question as to how one would sample and subsequently monitor these micro-operations. The topic of sampling has always been an area of concern to the traditional macro-operations as well. Sampling seemed to be a major problem in almost every PAT application discussed. An action item at these Summer Institutes was to address potential sampling system improvements that could work across industries. 

This book recognizes the important role that advances in miniaturization technology have had in improvements in the field of micro-instrumentation as it pertains to Process Analytical Technology (PAT). 

LIF detection is the most sensitive optical method so far, but is hard to miniaturize in order to satisfy the ultimate goal of a microfluidic chip that assembles all analytical processes within one micrometerscale microstructure. Therefore, how to achieve the miniaturization of fluorescence detection on microdevices is becoming an active field for lab-on-a-chip research. Several examples demonstrate recent advances in miniaturized LIF detection on the microchip. In 2005, Renzi et al. designed a hand-held microchip-based analytical instrument that combines fluidic, optics, electrical power, and interface modules and integrates the functions of fluidics, microseparation, lasers, power supplies etc., into an... 

In electrochemistry, reactions occur at large surfaces with comparatively higher current density. However, continuous advances in miniaturization shifted the possible range of reactions into the field... 

Advancement in miniaturization of microelectrode is possible due to the development of several micromachining techniques. Very small microelectrodes possess various extraordinary advantageous properties which enabled new fields of applications in the electrochemical systems. Limitations in... 

Recent aircraft design has focused on the development of unmanned aerial vehicles (UAVs). This class of aircraft has been successfully adapted to perform many of the same roles as manned aircraft but at lower cost. The absence of a pilot eliminates many of the safety and life support requirements and also changes the control objectives. For example, rapid acceleration or a bumpy trajectory can hinder a pilot s ability to cOTitrol the aircraft but do not affect the control system of a UAV. Another advantage of UAVs is that they can be used in environments that are xmdesirable for humans. This may include a combat zone or a toxic chemical plume. Moreover, many mission profiles do not require a large payload, and UAVs can be built much smaller to perform these missions because they do not have to support the extra weight of a pilot. Advancements in miniaturization have simultaneously made it possible to build smaller and smaller aircraft. 

A variety of components are either freely dissolved in this hydrophobic matrix or covalently anchored onto the polymeric backbone of the membrane. These membrane components mediate the selective extraction of many analytes and also make sure that the ISE membrane exhibits ion-exchanger properties. Thus far, liq-uid/polymer membrane ISEs for more than five-dozen analytes have been described [15, 27, 28]. They are routinely used in clinical analysis for the direct potentiometric detection of many anions and cations, and their application is steadily broadening with the advent of more selective membrane materials, advances in miniaturization, and the availability of more rugged sensors. Two main classes of liquid membrane ISEs can be distinguished one that contains an ion-exchanger without molecular receptor properties, and the other that is based on highly selective ionophores. While modem chemical research is mainly directed to the improvement of the second class, many commercial IS Es are still based on the first. 

Advances in miniaturization and biosensors are expected to facilitate noninvasive monitoring of neuronal signaling and intracellular environment, thus greatly improving the diagnosis and treatment of nervous-system disorders. 

With advances in miniaturization, microlenses continue to play important roles in many fields, including artificial implementation of compound eyes [2,19], optical commimication [20,21], photolithography [3,22], biomedical imaging systems [2,23,24], orthoscopic three-dimensional (3D) imaging [25,26], and labs on chips [4,27-29]. 

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