Micro and Nano Systems Letters最新文献

{"title":"Hydrophobic surface for direct PEGDA micro-pattern fabrication","authors":"Anna Danielak,&nbsp;Juhee Ko,&nbsp;Aminul Islam,&nbsp;David Bue Pedersen,&nbsp;Jungchul Lee","doi":"10.1186/s40486-023-00169-8","DOIUrl":"10.1186/s40486-023-00169-8","url":null,"abstract":"<div><p>Photopolymerization of hydrogels films has gained interest in many biomedical and industrial fields. Hydrogel micro-patterns fabricated directly on a device are used as filtering barriers, however, due to weak mechanical properties, these parts require a stable support but deposition of hydrogel in non-polymerized state brings a risk of sinking inside the structure. These limitations can be overcome by applying a hydrophobic surface. This paper presents a novel two-step method, in which a hydrophobic surface was designed and manufactured using mask-projection vat photopolymerization additive manufacturing (VPP). Afterwards, PEGDA-based hydrogel photopolymers were deposited on the surface and a micro-scale patterns were cured. The parts were subjected to water immersion and heating in order to evaluate the swelling and shrinking behaviour of hydrogel. The parts remained stable on the substrate and maintained the properties and the results revealed the shape retention over 97%. This work shows that VPP can be applied in the manufacturing of hydrophobic surfaces for hydrogel photopolymer deposition and curing without sacrificing critical properties.</p><h3>Graphical Abstract</h3>\u0000 <figure><div><div><div><picture><source><img></source></picture></div></div></div></figure>\u0000 </div>","PeriodicalId":704,"journal":{"name":"Micro and Nano Systems Letters","volume":"11 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2023-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://mnsl-journal.springeropen.com/counter/pdf/10.1186/s40486-023-00169-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4305878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advancements in visible-light-driven double perovskite nanoparticles for photodegradation","authors":"Runia Jana,&nbsp;P. Mary Rajaitha,&nbsp;Sugato Hajra,&nbsp;Hoe Joon Kim","doi":"10.1186/s40486-023-00168-9","DOIUrl":"10.1186/s40486-023-00168-9","url":null,"abstract":"<div><p>Perovskites are of significant interest in the field of photocatalysis. To date, many perovskite nanostructures have been developed, and their applications in photocatalysis have been studied. There has been considerable improvement in the research on metal doping in the perovskite structure to improve their optical and structural properties. This mini-review examines the recent progress in the synthesis of lead-free double perovskite nanoparticles and their application in visible-light photocatalysis. Lead-free perovskites are emerging as an eco-friendly solution in energy, electrochemistry, and sensing. Double perovskites are known for their flexible structural, optical, and morphological properties due to their lattice framework having a general form AAʹBBʹO₆. They are more useful for hydrogen evolution due to their higher conduction band potential than simple perovskites. Here, we summarize the current progress and provide insights for the future development of double perovskites toward efficient photodegradation.</p></div>","PeriodicalId":704,"journal":{"name":"Micro and Nano Systems Letters","volume":"11 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2023-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://mnsl-journal.springeropen.com/counter/pdf/10.1186/s40486-023-00168-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4875128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stimuli-responsive polymer-based bioinspired soft robots","authors":"Swati Panda,&nbsp;Sugato Hajra,&nbsp;P. Mary Rajaitha,&nbsp;Hoe Joon Kim","doi":"10.1186/s40486-023-00167-w","DOIUrl":"10.1186/s40486-023-00167-w","url":null,"abstract":"<div><p>Soft robotics enables various applications in certain environments where conventional rigid robotics cannot deliver the same performance due to their form factor and stiffness. Animals use their soft external organs to carry out activities in response to challenging natural environments efficiently. The objective of soft robots is to provide biologically inspired abilities and enable adaptable and flexible interactions with complex objects and surroundings. Recent advances in stimuli-responsive soft robot technology have heavily used polymer-based multifunctional materials. Soft robots with incredibly sophisticated multi-mechanical, electrical, or optical capabilities have demonstrated the ability to modify their shape intelligently in response to external stimuli, such as light, electricity, thermal gradient, and magnetic fields. This short review covers recent advances in scientific techniques for incorporating multifunctional polymeric materials into stimuli-responsive bioinspired soft robots and their applications. We also discuss how biological inspiration and environmental effects can provide a viable viewpoint for bioinspired design in the innovative field of soft robotics. Lastly, we highlight the future outlooks and prospects for soft, stimuli-responsive, bio-inspired robots.</p></div>","PeriodicalId":704,"journal":{"name":"Micro and Nano Systems Letters","volume":"11 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2023-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://mnsl-journal.springeropen.com/counter/pdf/10.1186/s40486-023-00167-w","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4352672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"3D printing fabrication process for fine control of microneedle shape","authors":"Jinwoong Jeong,&nbsp;Jaeu Park,&nbsp;Sanghoon Lee","doi":"10.1186/s40486-022-00165-4","DOIUrl":"10.1186/s40486-022-00165-4","url":null,"abstract":"<div><p>Microneedle electrode (ME) is used to monitor bioelectrical signals by penetrating via the skin, and it compensates for a limitation of surface electrodes. However, existing fabrication of ME have limited in controlling the shape of microneedles, which is directly relevant to the performance and durability of microneedles as an electrode. In this study, a novel method using 3D printing is developed to control needle bevel angles. By controlling the angle of printing direction, needle bevel angles are changed. Various angles of printing direction (0–90°) are investigated to fabricate moldings, and those moldings are used for microneedle fabrications using biocompatible polyimide (PI). The height implementation rate and aspect ratio are also investigated to optimize PI microneedles. The penetration test of the fabricated microneedles is conducted in porcine skin. The PI microneedle of 1000 μm fabricated by the printing angle of 40° showed the bevel angle of 54.5°, which can penetrate the porcine skin. The result demonstrates that this suggested fabrication can be applied using various polymeric materials to optimize microneedle shape.</p></div>","PeriodicalId":704,"journal":{"name":"Micro and Nano Systems Letters","volume":"11 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2023-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://mnsl-journal.springeropen.com/counter/pdf/10.1186/s40486-022-00165-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4082055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ethanol-sensing properties of cobalt porphyrin-functionalized titanium dioxide nanoparticles as chemiresistive materials that are integrated into a low power microheater","authors":"Kwanhun Kim,&nbsp;Yunsung Kang,&nbsp;Kyubin Bae,&nbsp;Jongbaeg Kim","doi":"10.1186/s40486-022-00146-7","DOIUrl":"10.1186/s40486-022-00146-7","url":null,"abstract":"<div><p>Gaseous ethanol detection has attracted significant interest owing to its practical applications such as in breath analysis, chemical process monitoring, and safety evaluations of food packaging. In this study, titanium dioxide (TiO₂) nanoparticles functionalized with cobalt porphyrin (CoPP) are utilized as resistive ethanol-sensing materials, and are integrated with a suspended micro-heater for low power consumption. The micro-heater with the suspended structure inhibits substrate heat transfer, resulting in power consumption as low as 18 mW when the operating temperature is approximately 300 °C. CoPP functionalization allows an enhanced response (197.8%) to 10 ppm ethanol compared to that of pristine TiO₂ nanoparticles. It is confirmed that the sensor response is reliable upon exposure to 10 ppm ethanol for three cycles. In addition, responses of different magnitude are obtained under exposure to ethanol at various concentrations from 9 to 1 ppm, indicating that the resistance change originates from a charge transfer between the sensing materials and target gas. The sensing mechanism of CoPP-functionalized TiO₂ in relation to charge transfer is analyzed, and the performance of the proposed sensor with previously reported TiO₂-based ethanol sensors is compared. Considering that it is processed by batch fabrication, consumes low power, and offers high sensitivity, the proposed sensor is promising for use as a portable sensor in the distributed monitoring of gaseous ethanol.</p></div>","PeriodicalId":704,"journal":{"name":"Micro and Nano Systems Letters","volume":"10 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2022-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://mnsl-journal.springeropen.com/counter/pdf/10.1186/s40486-022-00146-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4743008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Toluene sensing characteristics of tin oxide-based gas sensor deposited with various amounts of metalloporphyrin","authors":"Byeonghwa Cho,&nbsp;Jongbaeg Kim","doi":"10.1186/s40486-022-00145-8","DOIUrl":"10.1186/s40486-022-00145-8","url":null,"abstract":"<div><p>In this study, the sensing characteristics of tin oxide-based gas sensors deposit with different amounts of metalloporphyrin, which is a functionalization substance, are evaluated. The mass of metalloporphyrin deposited is 3, 10, 20, 30, and 40 mg for 5 different sensors prepared. The deposition of 3 mg of metalloporphyrin result in an island form of functionalization instead of a thin film; meanwhile, thin films with thicknesses of 25, 35, 74, and 92 nm are formed for the other four cases. As the deposition amount of metalloporphyrin increase, the performance of the sensor deteriorate. The samples are prepared by subdividing the amount of metalloporphyrin source to determine the optimized deposition amount. A sample is prepared with deposition amounts ranging between 1 to 10 mg. The sensors deposit with 3–5 mg metalloporphyrin has excellent response, response, and recovery time characteristics.</p></div>","PeriodicalId":704,"journal":{"name":"Micro and Nano Systems Letters","volume":"10 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2022-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://mnsl-journal.springeropen.com/counter/pdf/10.1186/s40486-022-00145-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4346790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Green synthesis of silver nanoparticles and its antibacterial activity using fungus Talaromyces purpureogenus isolated from Taxus baccata Linn.","authors":"Ankush Sharma,&nbsp;Anand Sagar,&nbsp;Jagriti Rana,&nbsp;Reena Rani","doi":"10.1186/s40486-022-00144-9","DOIUrl":"10.1186/s40486-022-00144-9","url":null,"abstract":"<div><p>The present study is focused on the synthesis of silver nanoparticles (AgNPs) utilizing endophytic fungus <i>Talaromyces purpureogenus</i>, isolated from <i>Taxus baccata</i> Linn. Extracellular extract of <i>Talaromyces purpureogenus</i> has shown occurrence of secondary metabolites viz. terpenoids and phenols. Gas chromatography-mass spectroscopy analysis showed the presence of 16 compounds. Techniques like Ultraviolet–visible spectroscopy, Fourier transform infrared spectroscopy, dynamic light scattering, field emission gun scanning electron microscopy, high-resolution transmission electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction were employed to characterize the synthesized AgNPs. UV–Vis spectroscopy showed sharp peaks at 380–470 nm which indicates the presence of metallic silver. FTIR analysis showed the presence of various functional groups like phenols, hydroxyl groups, and primary amines. In DLS, Z-average size and PdI of synthesized AgNPs were 240.2 r.nm and 0.720 respectively, with zeta potential − 19.6 mV. In FEG-SEM and HRTEM the spherical AgNPs showed diameter in the range of 30–60 nm. In EDS analysis the weight percent of Ag is 67.26% and atomic percent is 43.13%. From XRD analysis the size of AgNPs was found to be 49.3 nm with face-centered cubic crystalline nature of fungal synthesized AgNPs. These nanoparticles have shown significant antibacterial activity against tested strains viz. <i>Listeria monocytogenes</i> (13 ± 0.29 mm), <i>Escherichia coli</i> (17 ± 0.14 mm), <i>Shigella dysenteriae</i> (18 ± 0.21 mm) and <i>Salmonella typhi</i> (14 ± 0.13 mm). These synthesized AgNPs have shown effective free radical scavenging activity against 2,2′-diphenyl-1-picrylhydrazyl. The present study showed that the endophytic fungus <i>Talaromyces purpureogenus</i> can be used as a prominent source to synthesize AgNPs by using biological, ecofriendly, and in a non-toxic way accompanied by antibacterial and antioxidant properties which further can reduce the harvesting pressure faced by <i>Taxus baccata.</i></p><h3>Graphical Abstract</h3>\u0000 <figure><div><div><div><picture><source><img></source></picture></div></div></div></figure>\u0000 </div>","PeriodicalId":704,"journal":{"name":"Micro and Nano Systems Letters","volume":"10 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2022-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://mnsl-journal.springeropen.com/counter/pdf/10.1186/s40486-022-00144-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"5087555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multiple ratiometric nanothermometry using semiconductor BiFeO3 nanowires and quantitative validation of thermal sensitivity","authors":"K. Prashanthi,&nbsp;K. Krishna Mohan,&nbsp;Željka Antić,&nbsp;Kaveh Ahadi,&nbsp;Miroslav D. Dramicanin","doi":"10.1186/s40486-022-00143-w","DOIUrl":"10.1186/s40486-022-00143-w","url":null,"abstract":"<div><p>Here, we report a very sensitive, non-contact, ratio-metric, and robust luminescence-based temperature sensing using a combination of conventional photoluminescence (PL) and negative thermal quenching (NTQ) mechanisms of semiconductor BiFeO₃ (BFO) nanowires. Using this approach, we have demonstrated the absolute thermal sensitivity of ~ 10 mK⁻¹ over the 300–438 K temperature range and the relative sensitivity of 0.75% K⁻¹ at 300 K. Further, we have validated thermal sensitivity of BFO nanowires quantitatively using linear regression and analytical hierarchy process (AHP) and found close match with the experimental results. These results indicated that BFO nanowires are excellent candidates for developing high‐performance luminescence-based temperature sensors.</p><h3>Graphical abstract</h3>\u0000 <figure><div><div><div><picture><source><img></source></picture></div></div></div></figure>\u0000 </div>","PeriodicalId":704,"journal":{"name":"Micro and Nano Systems Letters","volume":"10 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2022-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://mnsl-journal.springeropen.com/counter/pdf/10.1186/s40486-022-00143-w","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4726482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Green synthesized plant-based silver nanoparticles: therapeutic prospective for anticancer and antiviral activity","authors":"Nancy Jain,&nbsp;Priyanshu Jain,&nbsp;Devyani Rajput,&nbsp;Umesh Kumar Patil","doi":"10.1186/s40486-021-00131-6","DOIUrl":"https://doi.org/10.1186/s40486-021-00131-6","url":null,"abstract":"<p>Nanotechnology holds an emerging domain of medical science as it can be utilized virtually in all areas. Phyto-constituents are valuable and encouraging candidates for synthesizing green silver nanoparticles (AgNPs) which possess great potentials toward chronic diseases. This review gives an overview of the Green approach of AgNPs synthesis and its characterization. The present review further explores the potentials of Phyto-based AgNPs toward anticancer and antiviral activity including its probable mechanism of action. Green synthesized AgNPs prepared by numerous medicinal plants extract are critically reviewed for cancer and viral infection. Thus, this article mainly highlights green synthesized Phyto-based AgNPs with their potential applications for cancer and viral infection including mechanism of action and therapeutic future prospective in a single window. </p>","PeriodicalId":704,"journal":{"name":"Micro and Nano Systems Letters","volume":"9 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2021-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1186/s40486-021-00131-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4479604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High speed silicon wet anisotropic etching for applications in bulk micromachining: a review","authors":"Prem Pal,&nbsp;Veerla Swarnalatha,&nbsp;Avvaru Venkata Narasimha Rao,&nbsp;Ashok Kumar Pandey,&nbsp;Hiroshi Tanaka,&nbsp;Kazuo Sato","doi":"10.1186/s40486-021-00129-0","DOIUrl":"https://doi.org/10.1186/s40486-021-00129-0","url":null,"abstract":"<p>Wet anisotropic etching is extensively employed in silicon bulk micromachining to fabricate microstructures for various applications in the field of microelectromechanical systems (MEMS). In addition, it is most widely used for surface texturing to minimize the reflectance of light to improve the efficiency of crystalline silicon solar cells. In wet bulk micromachining, the etch rate is a major factor that affects the throughput. Slower etch rate increases the fabrication time and therefore is of great concern in MEMS industry where wet anisotropic etching is employed to perform the silicon bulk micromachining, especially to fabricate deep cavities and freestanding microstructures by removal of underneath material through undercutting process. Several methods have been proposed to increase the etch rate of silicon in wet anisotropic etchants either by physical means (e.g. agitation, microwave irradiation) or chemically by incorporation of additives. The ultrasonic agitation during etching and microwave irradiation on the etchants increase the etch rate. However, ultrasonic method may rupture the fragile structures and microwave irradiation causes irradiation damage to the structures. Another method is to increase the etching temperature towards the boiling point of the etchant. The etching characteristics of pure potassium hydroxide solution (KOH) is studied near the boiling point of KOH, while surfactant added tetramethylammonium hydroxide (TMAH) is investigated at higher temperature to increase the etch rate. Both these studies have shown a potential way of increasing the etch rate by elevating the temperature of the etchants to its boiling point, which is a function of concentration of etch solution. The effect of various kinds of additives on the etch rate of silicon is investigated in TMAH and KOH. In this paper, the additives which improve the etch rate have been discussed. Recently the effect of hydroxylamine (NH₂OH) on the etching characteristics of TMAH and KOH is investigated in detail. The concentration of NH₂OH in TMAH/KOH is varied to optimize the etchant composition to obtain improved etching characteristics especially the etch rate and undercutting which are important parameters for increasing throughput. In this article, different methods explored to improve the etch rate of silicon have been discussed so that the researchers/scientists/engineers can get the details of these methods in a single reference.</p>","PeriodicalId":704,"journal":{"name":"Micro and Nano Systems Letters","volume":"9 1","pages":""},"PeriodicalIF":3.6,"publicationDate":"2021-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"5155008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}