Hashimdeen, Shaikh Hafeez, Miodownik, Mark, and Edirisinghe, Mohan J.
PLoS ONE. Nov 18, 2014, Vol. 9 Issue 11
Robot, Tissue engineering, Robots, and Rapid prototyping
Author(s): Shaikh Hafeez Hashimdeen, Mark Miodownik, Mohan J. Edirisinghe [sup.*] Introduction A surge in demand for high throughput in the design and manufacture of complicated parts in a highly precise [...] In this work we bring together replicating rapid prototyping technology with electrohydrodynamic phenomena to develop a device with the ability to build structures in three-dimensions while simultaneously affording the user a degree of designing versatility and ease that is not seen in conventional computer numerically controlled machines. An attempt at reproducing an actual human ear using polycaprolactone was pursued to validate the hardware. Five different polycaprolactone solution concentrations between 7-15 wt% were used and printing was performed at applied voltages that ranged from 1 to 6 kV and at flow rates from 5[micro]l/min to 60[micro]l/min. The corresponding geometrical and aesthetic features of the printed constructs were studied to determine the effectiveness of the device. The 15 wt% concentration at 60[micro]l/min under an applied electric field of 6 kV was identified as the best operating parameters to work with.
Imaging technology, Rapid prototyping, and Imaging systems
Author(s): Jason E. Osborne, Joshua T. Dudman * Introduction A typical adult laboratory mouse used for experiments in neuroscience weighs approximately 30 grams. This modest body weight and size allows [...] A number of recent studies have provided compelling demonstrations that both mice and rats can be trained to perform a variety of behavioral tasks while restrained by mechanical elements mounted to the skull. The independent development of this technique by a number of laboratories has led to diverse solutions. We found that these solutions often used expensive materials and impeded future development and modification in the absence of engineering support. In order to address these issues, here we report on the development of a flexible single hardware design for electrophysiology and imaging both in brain tissue in vitro. Our hardware facilitates the rapid conversion of a single preparation between physiology and imaging system and the conversion of a given system between preparations. In addition, our use of rapid prototyping machines ('3D printers') allows for the deployment of new designs within a day. Here, we present specifications for design and manufacturing as well as some data from our lab demonstrating the suitability of the design for physiology in behaving animals and imaging in vitro and in vivo.
Printz, Adam D., Chan, Esther, Liong, Celine, Martinez, Rene S., and Lipomi, Darren J.
PLoS ONE. Dec 17, 2013, Vol. 8 Issue 12, e83939
Integrated circuit fabrication, Printing industry, Commercial printing industry -- Evaluation, Printing industry -- Evaluation, Indium -- Evaluation, Polymers -- Evaluation, Electrodes, and Rapid prototyping
Author(s): Adam D. Printz, Esther Chan, Celine Liong, Rene S. Martinez, Darren J. Lipomi * Introduction Transparent electrodes are essential components of nearly all displays, touch screens, and thin-film photovoltaic [...] This paper describes the fabrication of transparent electrodes based on grids of copper microwires using a non-photolithographic process. The process-'abrasion lithography'-takes two forms. In the first implementation (Method I), a water-soluble commodity polymer film is abraded with a sharp tool, coated with a conductive film, and developed by immersion in water. Water dissolves the polymer film and lifts off the conductive film in the unabraded areas. In the second implementation (Method II), the substrate is abraded directly by scratching with a sharp tool (i.e., no polymer film necessary). The abraded regions of the substrate are recessed and roughened. Following deposition of a conductive film, the lower profile and roughened topography in the abraded regions prevents mechanical exfoliation of the conductive film using adhesive tape, and thus the conductive film remains only where the substrate is scratched. As an application, conductive grids exhibit average sheet resistances of 17 [OHM] sq.sup.-1 and transparencies of 86% are fabricated and used as the anode in organic photovoltaic cells in concert with the conductive polymer, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). Compared to devices in which PEDOT:PSS alone serves as an anode, devices comprising grids of copper/nickel microwires and PEDOT:PSS exhibit lowered series resistance, which manifests in greater fill factor and power conversion efficiency. This simple method of forming micropatterns could find use in applications where cost and environmental impact should be minimized, especially as a potential replacement for the transparent electrode indium tin oxide (ITO) in thin-film electronics over large areas (i.e., solar cells) or as a method of rapid prototyping for laboratory-scale devices.
Sulfates -- Usage, Surface active agents, Rapid prototyping, Albumin, Skin, and Hazardous waste management industry
Author(s): Yusuf K. Demir 1,*, Zafer Akan 2, Oya Kerimoglu 1 Introduction The delivery of medicinal substances across the skin has been limited because of the unique barrier property of [...] Background The 'poke and release' strategy for the delivery of macromolecules using polymeric microneedle (MN) is of great importance because it eliminates microneedle reuse, the risks of biohazardous sharps and cross contamination, and it requires no special disposal mechanism. The main objective of this study was the determination of the stability and delivery of bovine serum albumin (BSA) that was transported across human skin via sodium alginate (SA) microneedle arrays (MNs) and SA needle free patches using two different analytical methods. Methodology and Findings The capability of two analytical methods, the bicinchoninic acid (BCA) assay and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), to precisely detect and quantify BSA within different types of polymeric MNs was assessed. The ex vivo protein release of BSA across dermatomed human abdominal skin from 10 w/w SA MNs was compared to that from needle-free patches using Franz diffusion cells. The developed applicator was mechanically characterized using a Texture Analyzer. The patch mold and its components were fabricated using a rapid prototyping machine. Conclusions/Significance The BCA method was able to precisely detect BSA that had been loaded into SA MNs. However, the use of SDS-PAGE as the analytical method resulted in significantly different amounts of BSA recovered from differently conditioned polymeric MNs. The permeation of BSA across dermatomed human abdominal skin by SA MNs, which were composed of 100 pyramidal needles, increased by approximately 15.4 fold compared to the permeation obtained with SA needle-free patches. The ease of use of the applicator during the release studies was also demonstrated, as was its mechanical characterization.