Stainless Steel Template Research Articles

Reproducible PDMS flexible superhydrophobic films: A method utilizing picosecond laser-etched templates

This paper provides a convenient, efficient and repeatable method for the preparation of flexible PDMS superhydrophobic films. The stainless steel template was etched with picosecond laser to create textures, which was then filled with PDMS and thermally cured to produce PDMS superhydrophobic films featuring corresponding microstructures. By constructing computational models of the microstructures and exploring the influence of laser scanning spacing on contact angle, the process parameters were optimized to obtain superhydrophobic PDMS films while ensuring the stability of microstructures. The microstructures showed straight lines spaced 55 μm apart, with each line connected by regular truncated cone structures. These structures formed Cassie contacts with the droplets, exhibiting a contact angle of 152.1° and a sliding angle of 9°. In addition, this study demonstrates the reproducibility of the PDMS superhydrophobic film preparation method and its effectiveness in delaying icing. The results indicate that the templates can be used for more than twenty replications, and the obtained PDMS superhydrophobic films have a delayed icing time of 3.3 times. These findings suggest that the PDMS superhydrophobic films have excellent performance and repeatable characteristics, making them suitable for various applications.

One step polishing to compare the mean surface roughness of nanohybrid and microhybrid composite resins

Objectives: This study's goal was to compare the mean surface roughness of nano hybrid and micro hybrid composites using a one-step polishing method. This comparison was made based on the idea that a material with reduced surface roughness will exhibit superior perishability, aesthetics, surface & optical properties, which means less wear, less staining, low plaque, and low caries rate. Methodology: This comparative study was carried out in April 2023 at the Ayub Medical College in Abbottabad, Pakistan, with a sample size of 100 (50 in each group), determined by the WHO calculator. Using a mechanical stainless steel template, 120 composite resin specimens mounted on acrylic blocks with dimensions of 2 mm x 3 mm x 3 mm were created. Results: 100 samples, separated into two groups, were used in this study. According to descriptive statistics, mean surface roughness and standard deviations for Nano hybrid composite in Group A were recorded as 0.076+0.025 and for Micro hybrid composite in Group B, they were 0.001+0.036. Conclusion: After polishing with a one-step procedure, there is a noticeable difference between the surface roughness of nano hybrid and micro hybrid composite resins, indicating that the former has higher polish ability than the latter.

Use of Foaming Disinfectants and Cleaners to Reduce Aerobic Bacteria and Salmonella on Poultry Transport Coops

Simple SummaryChicken coops are rarely washed and can soil poultry carcasses with fecal bacteria that may make people sick. Our laboratory applied two commercially available products to experimentally contaminated coops. One product contained bleach, potassium hydroxide and a foaming agent. The other product contained vinegar and hydrogen peroxide and was mixed with a detergent. Both products were applied using a firefighting apparatus known as a compressed air foam system (CAFS). These materials were washed away using a garden hose or pressure washer as the treatments called for. Surface swabs were collected prior to and after each treatment to determine the reduction of bacteria on the surface, which would be an indicator of sanitation. We found that both treatments significantly made the surface cleaner when compared to water alone. The application of these products via a CAFS may be a practical and expedient way to clean and disinfect poultry cages.Transport coops are infrequently washed and have been demonstrated to cross-contaminate broiler carcasses. We hypothesized that peracetic acid or a chlorinated cleaner, commonly used within poultry processing plants, can also be used to disinfect transport coops when applied via a compressed air foam system (CAFS). A mixture of fresh layer manure and concentrated Salmonella Typhimurium (ST) was evenly applied to the floors of four pre-cleaned transport coops and allowed to dry for thirty minutes. Treatments consisted of a (1) water rinse only, (2) product application with a water rinse, (3) product application followed by power washing and (4) power washing followed by application of product. Each foaming treatment was applied with a compressed air foam system and allowed 10 min of contact time. Samples were aseptically collected from the transport coops prior to and following treatment using a sterile 2 × 2-inch stainless steel template and a gauze swab pre-enriched with buffered peptone water. The chlorinated cleaner significantly (p < 0.05) reduced aerobic bacteria and ST by 3.18 to 4.84 logs across application methods. The peroxyacetic acid (PAA) disinfectant significantly (p < 0.05) reduced aerobic bacteria and ST by 3.99 to 5.17 logs across application methods. These data indicate that a compressed air foam system may be used in combination with a commercially available cleaner or disinfectant to reduce aerobic bacteria and ST on the surfaces of commercial poultry transport coops.

Multicenter evaluation of a new closed system drug-transfer device in reducing surface contamination by antineoplastic hazardous drugs

Results of a study to evaluate the effectiveness of a recently introduced closed system drug-transfer device (CSTD) in reducing surface contamination during compounding and simulated administration of antineoplastic hazardous drugs (AHDs) are reported. Wipe samples were collected from 6 predetermined surfaces in compounding and infusion areas of 13 U.S. cancer centers to establish preexisting levels of surface contamination by 2 marker AHDs (cyclophosphamide and fluorouracil). Stainless steel templates were placed over the 6 previously sampled surfaces, and the marker drugs were compounded and infused per a specific protocol using all components of the CSTD. Wipe samples were collected from the templates after completion of tasks and analyzed for both marker AHDs. Aggregated results of wipe sampling to detect preexisting contamination at the 13 study sites showed that overall, 66.7% of samples (104 of 156) had detectable levels of at least 1 marker AHD; subsequent testing after CSTD use per protocol found a sample contamination rate of 5.8% (9 of 156 samples). In the administration areas alone, the rate of preexisting contamination was 78% (61 of 78 samples); with use of the CSTD protocol, the contamination rate was 2.6%. Twenty-six participants rated the CSTD for ease of use, with 100% indicating that they were satisfied or extremely satisfied. A study involving a rigorous protocol and 13 cancer centers across the United States demonstrated that the CSTD reduced surface contamination by cyclophosphamide and fluorouracil during compounding and simulated administration. Participants reported that the CSTD was easy to use.

Magnetic granularity in pulsed laser deposited YBCO films on technical templates at 5 K

The manifestation of granularity in the superconducting properties of pulsed laser deposited YBCO films on commercially available metallic templates was investigated by scanning Hall probe microscopy at 5 K and was related to local orientation mapping of the YBCO layer. The YBCO films on stainless steel templates with a textured buffer layer of yttrium stabilized ZrO2 grown by alternating beam assisted deposition have a mean grain size of less than with a sharp texture. This results in a homogeneous trapped field profile and spatial distribution of the current density. On the other hand, YBCO films on biaxially textured NiW substrates show magnetic granularity that persists down to a temperature of 5 K and up to an applied magnetic field of 4 T. The origin of the granular field profile is directly correlated to the microstructural properties of the YBCO layer adopted from the granular NiW substrate which leads to a spatially inhomogeneous current density. Grain-to-grain in-plane tilts lead to grain boundaries that obstruct the current while out-of-plane tilts mainly affect the grain properties, resulting in areas with low . Hence, not all grain boundaries cause detrimental effects on since the orientation of individual NiW grains also contributes to observed inhomogeneity and granularity.

Abstract 4231: Significant reduction in workplace contamination of antineoplastic hazardous drugs in 13 U.S. hospitals following utilization of a new closed-system drug transfer device

Abstract Background: Adverse effects of worker exposure to antineoplastic hazardous drugs (AHD) have been well documented with dermal absorption from contaminated surfaces in the work environment being one of the most well researched sources of exposure. Multiple studies have documented decreased surface contamination when using CSTDs for AHD handling. Decreased surface contamination should result in decreased worker exposure and decreased risk of adverse effects. Purpose: The purpose of this study was to determine the effectiveness of a new CSTD in reducing surface contamination of marker AHDs cyclophosphamide (CP) and 5-fluorouracil (5FU) during compounding and administration in multiple cancer centers, using surface wipe-sampling methodology. The results of the wipe sampling were compared to existing contamination in the sites and to similar studies in peer-reviewed literature to determine relative effectiveness. Methods: Wipe samples of six predetermined surfaces were collected in designated compounding and infusion areas of 13 cancer centers to establish the preexisting level of surface contamination with two marker AHDs. Stainless steel templates of approximately 500 cm2 were placed over previously sampled surfaces, and a specific protocol of set doses of the AHDs were compounded and infused, using all of the components of the new CSTD system, over the templates. Wipe samples of the templates were collected following the completion of tasks and analyzed for both marker AHDs. Results: A total of 312 wipe samples were collected from the 13 centers, 156 at baseline and 156 with the CSTD. All samples were reported as ng/cm2 with the analytical limit of detection (LOD) for each drug being 0.002 ng/500 cm2. In the aggregate results of 13 sites sampled for existing contamination, 67% of wipe samples had detectable levels of the AHDs with a range of LOD to 19.880 ng/cm2 of 5FU and 0.648 ng/cm2 of CP. With the new CSTD the contaminated samples were reduced to 5.8% with a range LOD to 0.004ng/cm2 of 5FU and 2.60ng/cm2 of CP. Conclusions: The new CSTD significantly reduced surface contamination by the marker AHDs during both compounding and administration. Compared to published results of two multi-site studies of another CSTD for compounding, the new CSTD is superior in reducing surface contamination with marker AHDs, as determined by wipe sampling of similar surfaces. Research reported in this study was supported by the National Cancer Institute (NCI) of the National Institutes of Health (NIH) under award number 5R44CA153636. Citation Format: Timothy Tyler, Luci Power. Significant reduction in workplace contamination of antineoplastic hazardous drugs in 13 U.S. hospitals following utilization of a new closed-system drug transfer device [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4231. doi:10.1158/1538-7445.AM2017-4231

Design and Fabrication of a Precision Template for Spine Surgery Using Selective Laser Melting (SLM).

In order to meet the clinical requirements of spine surgery, this paper proposes the fabrication of the customized template for spine surgery through computer-aided design. A 3D metal printing-selective laser melting (SLM) technique was employed to directly fabricate the 316L stainless steel template, and the metal template with tiny locating holes was used as an auxiliary tool to insert spinal screws inside the patient’s body. To guarantee accurate fabrication of the template for cervical vertebra operation, the contact face was placed upwards to improve the joint quality between the template and the cervical vertebra. The joint surface of the printed template had a roughness of Ra = 13 ± 2 μm. After abrasive blasting, the surface roughness was Ra = 7 ± 0.5 μm. The surgical metal template was bound with the 3D-printed Acrylonitrile Butadiene Styrene (ABS) plastic model. The micro-hardness values determined at the cross-sections of SLM-processed samples varied from HV0.3 250 to HV0.3 280, and the measured tensile strength was in the range of 450 MPa to 560 MPa, which showed that the template had requisite strength. Finally, the metal template was clinically used in the patient’s surgical operation, and the screws were inserted precisely as the result of using the auxiliary template. The geometrical parameters of the template hole (e.g., diameter and wall thickness) were optimized, and measures were taken to optimize the key geometrical units (e.g., hole units) in metal 3D printing. Compared to the traditional technology of screw insertion, the use of the surgical metal template enabled the screws to be inserted more easily and accurately during spinal surgery. However, the design of the high-quality template should fully take into account the clinical demands of surgeons, as well as the advice of the designing engineers and operating technicians.

Application of bacteriophages to reduce biofilms formed by hydrogen sulfide producing bacteria on surfaces in a rendering plant.

Hydrogen sulfide producing bacteria (SPB) in raw animal by-products are likely to grow and form biofilms in the rendering processing environments, resulting in the release of harmful hydrogen sulfide (H2S) gas. The objective of this study was to reduce SPB biofilms formed on different surfaces typically found in rendering plants by applying a bacteriophage cocktail. Using a 96-well microplate method, we determined that 3 SPB strains of Citrobacter freundii and Hafnia alvei are strong biofilm formers. Application of 9 bacteriophages (10(7) PFU/mL) from families of Siphoviridae and Myoviridae resulted in a 33%-70% reduction of biofilm formation by each SPB strain. On stainless steel and plastic templates, phage treatment (10(8) PFU/mL) reduced the attached cells of a mixed SPB culture (no biofilm) by 2.3 and 2.7 log CFU/cm(2) within 6 h at 30 °C, respectively, as compared with 2 and 1.5 log CFU/cm(2) reductions of SPB biofilms within 6 h at 30 °C. Phage treatment was also applied to indigenous SPB biofilms formed on the environmental surface, stainless steel, high-density polyethylene plastic, and rubber templates in a rendering plant. With phage treatment (10(9) PFU/mL), SPB biofilms were reduced by 0.7-1.4, 0.3-0.6, and 0.2-0.6 log CFU/cm(2) in spring, summer, and fall trials, respectively. Our study demonstrated that bacteriophages could effectively reduce the selected SPB strains either attached to or in formed biofilms on various surfaces and could to some extent reduce the indigenous SPB biofilms on the surfaces in the rendering environment.

Evaluation of the Effects of a Mixture of Organic Acids and Duration of Storage on the Survival of Salmonella on Turkey Carcasses

Samples from turkey carcasses previously inoculated with Salmonella Enteritidis 33/66 were subjected to the effect of various mixtures of equal parts of organic acid solutions (acetic, ascorbic, citric, lactic, and tartaric acids). The first part of the study concerned analysis of the influence of the mixtures of organic acids over 15 or 30 min on Salmonella Enteritidis on turkey carcasses. Turkey breast samples were inoculated with Salmonella Enteritidis at 3.7, 2.7, 1.7, 0.7, and 0.07 log CFU. The antibacterial effectiveness of the organic acids differed depending on the initial population of Salmonella on the turkey carcasses. Salmonella was most sensitive to mixtures of equal parts of 1% ascorbic, 1% citric, and 1% tartaric acids. The second part of the study involved determining the influence the organic acid mixtures had on survival of Salmonella Enteritidis on turkey meat stored at 4°C for 2, 4, or 6 days. The level of Salmonella was determined using a most-probable-number method. Salmonella Enteritidis was inoculated into a nutrient broth, incubated at 37°C for 24 h, and then added to the diluent in which the turkey breast samples were immersed for 5 min. The initial Salmonella level of the control samples of turkey breast following immersion was determined in each analysis. After storage at 4°C, turkey samples were transferred to the organic acid solutions for 15 min. Stainless steel templates were used to swab 50 cm(2) of the turkey breast samples. During storage at 4°C, the Salmonella level in the meat samples decreased. The largest decrease occurred at 4°C after 6 days with equal parts of 1% acetic acid, 1% lactic acid, and 1% tartaric acid. Thus, treatment of raw turkey breasts with a mixture of organic acids is a promising option for reducing the risk of the presence of Salmonella.

Rapid fabrication of thermoplastic polymer refractive microlens array using contactless hot embossing technology.

A thermoplastic polymer refractive microlens array has been rapidly fabricated by contactless hot embossing technology through the stainless steel template with micro through-holes array, which has a diameter of 150 µm and a pitch of 185 µm. By optimizing the technical parameters including heating and demoulding temperature, loading pressure, loading and pressure holding time, a series of high quality microlenses arrays of different sags could be obtained. In addition, the sag and the radius of curvature of the microlens are controllable. The geometrical and optical properties of the microlenses are measured and the influence of temperature and pressure duration on the optical properties of the microlenses are analysed. The results show good surface features and optical performances. Unlike previous contactless hot embossing, a low cost and durable stainless steel template was utilized instead of silicon or nickel mold to avoid valuable equipments and complicated fabrication procedure. Besides, the whole contactless hot embossing process was absence of vacuum equipment. We think that the technology could be an attractive high flexibility method for enhancing efficiency and reducing cost.

A simple template-based transfer method to fabricate Bradbury-Nielsen gates with uniform tension for ion mobility spectrometry.

A Bradbury-Nielsen gate (BNG) consists of two interleaved and electrically isolated sets of wires. It is usually used to gate or modulate ion beams. Uniformly tense wires can remain parallel, equidistant, and coplanar over a wide working temperature range, which is critical to reliable BNG performance. Hence, this study analyzes the non-uniform tension of wires wound using traditional sequential winding methods in which the elastic modulus of the metal wire is much larger than that of the insulation substrate. To address this problem, a simple and reliable template-based transfer method is developed. First, a template with large elastic modulus is used to fabricate a wire mesh with uniform tension. The mesh is then transferred to the substrate. Theoretically, this method reduces the non-uniformity of the tension in wires to less than 2%; therefore, it is used to construct a BNG with stainless steel wire, a stainless steel template, and a printed circuit board substrate. The BNG was installed in our homebuilt ion mobility spectrometer. To confirm that the performance of the BNG meets the requirements of portable ion mobility spectrometry, signal intensity and resolution (approximately 30) were experimentally determined.

Metal tooth‐like surgical templates for tooth autotransplantation in adolescents

The aim of this study was to suggest a way to fabricate surgical templates to assist the surgeon in preparing the recipient socket when performing premolar autotransplantation. Premolars used previously for extractions of periodontal ligament (PDL) fibroblasts were used in this study as archetype of models for tooth transplantation. Eighty-four mandibular and maxillary first and second extracted premolars were reviewed. All teeth were extracted for orthodontic reasons. From these teeth, eight teeth were selected to serve as archetype of models in which all the other teeth were at equal size or smaller in maximum 2mm in M-D or B-L dimension. These teeth were sent to dental technician to perform identical archetype stainless steel templates. During autotransplantation immediately following donor tooth extraction, the appropriate template is chosen out of the toothlike stainless steel surgical templates and the donor tooth is then immediately replaced in its socket. This enables the surgeon to prepare the recipient site without manipulating the donor tooth and thus preventing damage to the PDL cells of the donor tooth. Only after the recipient site had been prepared to the appropriate size and shape according to the template, the donor tooth is removed from its socket, immediately placed at the recipient site and splinted as recommended. The advantage of the presented metal tooth-like surgical templates described in this study is that a set of stents has been produced by replicating different common shape adolescent premolars that reflect the biological variation in size and shape of these teeth.

Electromechanical performance of an ionic polymer–metal composite actuator with hierarchical surface texture

Two stainless steel templates were fabricated using electric-spark machining, and a hierarchical surface texture of ionic polymer was produced using both polishing and replication methods, which produced microscale and nanoscale groove-shaped microstructures at the surface of the polymer. The surface morphology of the Nafion membrane and metal electrode were observed using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). SEM and EDS line-scan analysis indicated that the interfacial surface area was considerably increased and an excellent metal electrode was obtained with the production of a hierarchical surface texture. The displacement, blocking force, and electric current were measured using home-built apparatus. The results revealed that the combined polishing and replication method significantly improved the electromechanical performance of the ionic polymer–metal composite (IPMC). Compared with sandblasted Nafion-based IPMC, the blocking force, displacement, and electric current of the replicated Nafion-based IPMC were 4.39, 2.35, and 1.87 times higher, respectively. The IPMC fabricated in this work exhibited a competitive blocking force compared with recently reported actuators.

Integrity of the Interface Between Denture Base and Soft Liner: A Scanning Electron Microscopic Study

Aims and objectives of the study was to study the integrity of the interface between the denture base and the soft liner when the thickness of the soft liner was 0.5, 1.0 and 2.0mm, and to study the integrity of the soft liner and denture base interface as influenced by aging process. 80 rectangular based specimens were fabricated using heat cured acrylic resin. The heat cured component of the specimen was fabricated from stainless steel template form by compression molding technique. Different thickness of silicone soft layer component was added to heat cured acrylic resin component of the specimen following the manufacturer's instructions to fabricate the group A, group B, group C and group D specimens. All the specimens were subjected to the same finishing and polishing procedures. The group A specimens was immediately scanned in scanning electron microscope after processing. A thermo statically controlled artificial saliva bath designed to maintain the temperature between 38±4°C was used to simulate the oral condition and to age the group B, group C and group D specimens for 3months after which they were subjected to scanning under a scanning electron microscope. All the aged specimens demonstrated two types of failures namely adhesive which occurred along the bond interface between the soft liner and the acrylic resin and adhesive and cohesive type of failure which occurred not only at the interface but also within the soft liner material itself. When the data was subjected to ANOVA, the group A specimens showed statistical significance with group B (P=0.006), group C (P=0.007) and group D specimens (P=0.004), the level of significance being (P<0.05). However, there was no statistical significance between group B and C (P=0.98), group C and D specimens (P=0.52), group B and D specimens (P=0.70), the level of significance being (P<0.05). Based on the results, statistical analysis of the results and within the limitations of this in vitro study the following conclusions can be drawn: The thickness of the liner did not show a statistically significant rate of failure on the integrity of the interface between the denture base resin and the soft liner and aging conditions simulating the clinical environment showed a statistically significant rate of failure on the integrity of the interface between the denture base resin and the soft liner.

Fabrication of anti-reflective structures using hot embossing with a stainless steel template irradiated by femtosecond laser

Periodic nanostructures have played critical roles in key components for optical applications. Femtosecond laser-induced periodic surface structures (FLIPSS) in nano scale on many material surfaces have drawn much attention in recent years. However, the relatively low throughput of the direct inducing process limits its potential in regard to high volume manufacturing. In this study, fast replication of FLIPSS on Polycarbonate (PC) films by gas-assisted a hot embossing process is demonstrated. A selected surface area of a stainless steel thin plate is irradiated by femtosecond laser pulses to form a kind of periodic anti-reflective nanostructure with a period measuring 600–700 nm. The stainless plate was then used as a template for the hot embossing process. PC films with periodic nanostructures are then replicated quickly. Compared to the original PC film, at least up to 5% of the reflectivity of the fabricated PC films with nanostructures was reduced. It proves that the gas-assisted hot embossing could procure uniform transcription for anti-reflection PC film with stainless steel template that is irradiated by femtosecond laser pulses.

Postapplication Formation of Pesticide Degradation Products in a Test House

PP-29-060 Background/Aims: Human exposure to preexisting degradation products of pesticides is a concern when conducting dose reconstruction studies where metabolic products are used to estimate exposure. The purpose of this research was to determine whether there was significant formation and translocation of pesticide degradates in an unoccupied test house where pesticides had been recently applied. Methods: To conduct the study, propoxur, cis/trans permethrin, and cypermethrin were sprayed in a simulated crack and crevice application in 1 room of the test house. Fipronil was applied to the same surfaces via syringe. Floor surface samples (n = 47) were collected at 1, 2, 3, 7, 14, 21, 28, and 35 days postapplication using isopropanol wetted cotton wipes and a stainless steel template with a 929-cm2 wiping area. No samples were taken from surfaces that had received direct pesticide application. The wipes were analyzed to determine the concentrations of the parent pesticides and the following degradation products: 2-iso-propoxyphenol, cis/trans 3-(2,2-dichlorovinyl)-3-3-dimethyl-(1-cyclopropane) carboxylic acid (cis/trans DCCA), 3-phenoxybenzoic acid (3-PBA), fipronil sulfone, fipronil sulfide, and fipronil desulfinyl. Results: Excepting a single sample where fipronil was not found, the parent pesticides were present in all samples. In contrast, the propoxur metabolite 2-iso-propoxyphenol was not detected in any sample. Fipronil sulfide was present at low levels (5.5 ± 3.0 pg/cm2) in 44 samples, whereas fipronil sulfone and desulfinyl were not found. Trans-DCCA, cis-DCCA, and 3-PBA were present in low, but quantifiable amounts, in 42, 16, and 9 wipes, respectively. Although 2 of the degradates were present in most of the samples, their continuous low level occurrence throughout the study period did not indicate an association with the pesticide application performed in the study. Conclusion: The study results indicate that formation and translocation of these metabolites to other surfaces after a recent indoor pesticide application may not be a significant factor affecting dose reconstruction studies.

Reconstruction of Orbital Wall Defects With Bioactive Glass Plates

Synthetic bioactive glass (BAG) is used in many surgical applications. Special bioactive glasses do not favor microbial growth. This study evaluated the clinical outcome of bioactive glass plates in reconstructive orbital surgery. In a retrospective series of 49 patients, 35 orbital floors and 6 orbital medial and superior walls were reconstructed after fronto-orbital trauma, and 8 patients were treated with BAG plates after fronto-orbital tumor resection. These patients were evaluated in terms of reconstruction materials, complications, and functional outcomes. During the 2-year follow-up, 3 of the 35 orbital floor trauma reconstructions were reoperated (9%) because of diplopia, and new reconstructions with BAG were performed. In all of the 8 patients with tumors and in 6 of the patients undergoing orbital wall reconstruction, the plates were in the correct position after reconstruction, and none had to be removed. One patient with a benign tumor and 7 of the 8 patients with malignant tumors survived to the 2-year follow-up. Reconstructive surgery of the orbit is one of the most demanding challenges in head and neck surgery. In orbital defect reconstruction, a BAG plate seems to be a well-tolerated and reliable reconstruction material alternative; however, BAG plates are brittle and rigid, and cannot be molded and shaped by a surgeon. The use of a stainless steel template of equal shape and size to a BAG plate is recommended to ameliorate this deficiency.

Self-assembled palladium nanowires by electroless deposition

A simple approach to the self-assembly production of palladium nanowires by electrolessdeposition on a porous stainless steel template is reported. Various arrays of self-assembledpalladium nanowires in the form of single wire, parallel and curved wires, intersections andnetwork structures are illustrated. This experimental result demonstrates that metalnanowires can be built in a self-assembled manner by the assembly of nanoparticlesgenerated in the initial stages of the deposition without any external field except thechemical reaction. Such self-assembled nanowires may attract engineering applicationsbecause the electroless deposition process and the preparation of the substrate are simpleand inexpensive.

Vacuum-assisted thermal bonding of plastic capillary electrophoresis microchip imprinted with stainless steel template

An improved fabrication of poly(methyl methacrylate) (PMMA)-based capillary electrophoresis microchips has been demonstrated. The microchannel structures on PMMA substrates were generated by one-step hot embossing procedure using a stainless steel template. Hundreds of patterned PMMA substrates have been successfully obtained using the single metal template. Sequent microchannel enclosure with high yield up to 90% was accomplished by a vacuum-assisted thermal bonding method. The results of profilometric scanning of separated substrates showed the dimensions of the channels were well preserved during the bonding process. Finally, analytical functionalities of these PMMA microchips were demonstrated by performing fast electrophoretic separations and high sensitive end-column amperometric detections of dopamine and catechol. The entire fabrication methodology may also be useful for preparation of other thermoplastic microfluidic systems.

Fabrication and characterization of poly(methyl methacrylate) microchannels by in situ polymerization with a novel metal template.

A stainless steel template for the fabrication of plastic microfluidic devices has been developed by photolithography and chemical etching technique. The preparation process of the template is simple, rapid, and low-cost. The cross sectional profiles of raised microchannels on the template are trapezoidal. The surface roughness of the templates was controlled down to 190 nm. The template can be used repeatedly to generate devices reproducibly. The microfluidic devices of poly(methyl methacrylate) (PMMA) were fabricated by in situ polymerization using the templates. The reproducibility of the fabricated microchannel is high and the relative standard deviation is 0.7% by the in situ polymerization approach. Some physical properties of the polymerized microchannels were characterized including the transparency, the thermal deformation temperature, and the dimensional information. Current monitoring was used to evaluate the electroosmotic flow within the microchannels under the electric field strength of 300 V/cm.