scholarly journals Bio-inspired smart surface to achieve controllable locomotion through adjustable anisotropic friction

Friction ◽  
2021 ◽  
Author(s):  
Zhongying Ji ◽  
Shiyu Qin ◽  
Shuanhong Ma ◽  
Xin Jia ◽  
Xiaolong Wang ◽  
...  

AbstractAnisotropic friction generated by microstructured surfaces is crucial for performing functions such as directional locomotion and adhesion in biological systems. Hence, an epoxy-based shape memory polymer (SMP) incorporating Fe3O4 nanoparticles is used in this study to create a smart surface with oriented structures to mimic anisotropic friction and exploit human-developed controllable locomotion systems. Applying the specific properties of the epoxy-based SMP, fast switching friction can be achieved by adjusting the topography and stiffness of the microstructures on the surface. In addition, the photothermogenesis effect of Fe3O4 nanoparticles induces changes in the asymmetric topography and stiffness on the SMP surface under the irradiation of near-infrared (NIR) light, thereby inducing a rapid switching of the friction force. Furthermore, a microbot is created to demonstrate remotely controlled locomotion, such as unidirectional and round-trip movements, and braking by switching the friction force under NIR light. These results are promising for the design of new intelligent surfaces and interfaces; additionally, they may facilitate the investigation of biological structures and processes.

2020 ◽  
Author(s):  
Alex Stafford ◽  
Dowon Ahn ◽  
Emily Raulerson ◽  
Kun-You Chung ◽  
Kaihong Sun ◽  
...  

Driving rapid polymerizations with visible to near-infrared (NIR) light will enable nascent technologies in the emerging fields of bio- and composite-printing. However, current photopolymerization strategies are limited by long reaction times, high light intensities, and/or large catalyst loadings. Improving efficiency remains elusive without a comprehensive, mechanistic evaluation of photocatalysis to better understand how composition relates to polymerization metrics. With this objective in mind, a series of methine- and aza-bridged boron dipyrromethene (BODIPY) derivatives were synthesized and systematically characterized to elucidate key structure-property relationships that facilitate efficient photopolymerization driven by visible to NIR light. For both BODIPY scaffolds, halogenation was shown as a general method to increase polymerization rate, quantitatively characterized using a custom real-time infrared spectroscopy setup. Furthermore, a combination of steady-state emission quenching experiments, electronic structure calculations, and ultrafast transient absorption revealed that efficient intersystem crossing to the lowest excited triplet state upon halogenation was a key mechanistic step to achieving rapid photopolymerization reactions. Unprecedented polymerization rates were achieved with extremely low light intensities (< 1 mW/cm<sup>2</sup>) and catalyst loadings (< 50 μM), exemplified by reaction completion within 60 seconds of irradiation using green, red, and NIR light-emitting diodes.


Nanoscale ◽  
2021 ◽  
Author(s):  
Jinsong Xiong ◽  
Qinghuan Bian ◽  
Shuijin Lei ◽  
Yatian Deng ◽  
Kehan Zhao ◽  
...  

Near-infrared (NIR) light induced photothermal cancer therapy using nanomaterials as photothermal agents has attracted considerable research interest over the past few years. As the key factor in the photothermal therapy...


Biomedicines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 756
Author(s):  
Manoj Kumar Mahata ◽  
Ranjit De ◽  
Kang Taek Lee

Due to the unique properties of lanthanide-doped upconverting nanoparticles (UCNP) under near-infrared (NIR) light, the last decade has shown a sharp progress in their biomedicine applications. Advances in the techniques for polymer, dye, and bio-molecule conjugation on the surface of the nanoparticles has further expanded their dynamic opportunities for optogenetics, oncotherapy and bioimaging. In this account, considering the primary benefits such as the absence of photobleaching, photoblinking, and autofluorescence of UCNPs not only facilitate the construction of accurate, sensitive and multifunctional nanoprobes, but also improve therapeutic and diagnostic results. We introduce, with the basic knowledge of upconversion, unique properties of UCNPs and the mechanisms involved in photon upconversion and discuss how UCNPs can be implemented in biological practices. In this focused review, we categorize the applications of UCNP-based various strategies into the following domains: neuromodulation, immunotherapy, drug delivery, photodynamic and photothermal therapy, bioimaging and biosensing. Herein, we also discuss the current emerging bioapplications with cutting edge nano-/biointerfacing of UCNPs. Finally, this review provides concluding remarks on future opportunities and challenges on clinical translation of UCNPs-based nanotechnology research.


Author(s):  
Jiaxin Shen ◽  
Dandan Chen ◽  
Ye Liu ◽  
Guoyang Gao ◽  
Zhihe Liu ◽  
...  

Photodynamic therapy (PDT) is a promising method for cancer therapy and also may initiate unexpected damages to normal cells and tissues. Herein, we developed a near-infrared (NIR) light-activatable nanophotosensitizer, which...


2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Mary K. Popp ◽  
Imane Oubou ◽  
Colin Shepherd ◽  
Zachary Nager ◽  
Courtney Anderson ◽  
...  

Photothermal therapy (PTT) treatments have shown strong potential in treating tumors through their ability to target destructive heat preferentially to tumor regions. In this paper we demonstrate that PTT in a murine melanoma model using gold nanorods (GNRs) and near-infrared (NIR) light decreases tumor volume and increases animal survival to an extent that is comparable to the current generation of melanoma drugs. GNRs, in particular, have shown a strong ability to reach ablative temperatures quickly in tumors when exposed to NIR light. The current research tests the efficacy of GNRs PTT in a difficult and fast growing murine melanoma model using a NIR light-emitting diode (LED) light source. LED light sources in the NIR spectrum could provide a safer and more practical approach to photothermal therapy than lasers. We also show that the LED light source can effectively and quickly heatin vitroandin vivomodels to ablative temperatures when combined with GNRs. We anticipate that this approach could have significant implications for human cancer therapy.


2018 ◽  
Vol 115 (3) ◽  
pp. 501-506 ◽  
Author(s):  
Meng Qiu ◽  
Dou Wang ◽  
Weiyuan Liang ◽  
Liping Liu ◽  
Yin Zhang ◽  
...  

A biodegradable drug delivery system (DDS) is one the most promising therapeutic strategies for cancer therapy. Here, we propose a unique concept of light activation of black phosphorus (BP) at hydrogel nanostructures for cancer therapy. A photosensitizer converts light into heat that softens and melts drug-loaded hydrogel-based nanostructures. Drug release rates can be accurately controlled by light intensity, exposure duration, BP concentration, and hydrogel composition. Owing to sufficiently deep penetration of near-infrared (NIR) light through tissues, our BP-based system shows high therapeutic efficacy for treatment of s.c. cancers. Importantly, our drug delivery system is completely harmless and degradable in vivo. Together, our work proposes a unique concept for precision cancer therapy by external light excitation to release cancer drugs. If these findings are successfully translated into the clinic, millions of patients with cancer will benefit from our work.


2021 ◽  
Vol 32 (1) ◽  
pp. 015003
Author(s):  
Sang-Woo Seo ◽  
Youngsik Song ◽  
Hojjat Rostami Azmand

Abstract Controlled photothermal actuation of liquid release is presented using periodically arrayed hydrogel columns in a macroporous silicon membrane. Thermo-responsive hydrogel is mixed with Gold (Au) nanorods, and surface plasmon-induced local heating by near-infrared (NIR) light is utilized as an actuation method. We adopted theoretical modeling, which treats the hydrogel as a poro-viscoelastic medium to understand the mechanical and liquid transport properties of the hydrogel. To demonstrate the feasibility of the liquid release control using NIR light, we first characterized the temperature response of Au nanorod embedded hydrogel in the silicon membrane using its optical transmission behavior to confirm the successful device fabrication. Next, the liquid release characteristics from the structure were studied using fluorescent imaging of fluorescein dye solution while pulsed NIR light was illuminated on the structure. We successfully demonstrate that the liquid release can be controlled using remote NIR illumination from the presented structure. Considering the periodically arrayed configuration with high spatial resolution, this will have a potential prospect for optically-addressable chemical release systems, which benefit retina prosthesis interfaces.


Vascular ◽  
2021 ◽  
pp. 170853812110514
Author(s):  
Nail Kahraman ◽  
Gündüz Yümün ◽  
Deniz Demir ◽  
Kadir K Özsin ◽  
Sadık A Sünbül ◽  
...  

Objectives Varicose veins that cannot be seen with the naked eye can be easily detected with Near Infrared (NIR) light. With a minimally invasive procedure performed with NIR light guided, the need for reoperation is reduced, while optimal treatment of venous insufficiency and symptoms is provided. In this study, the detection of residual varicose veins after varicose vein surgery using NIR light and the results of treatment of sclerotherapy were investigated. Methods In this retrospective study, treatment and clinical outcomes of patients’ who underwent NIR light-guided foam sclerotherapy for Clinical-Etiology-Anatomy-Pathophysiology (CEAP) (C1, C2) stage residual varicose veins after surgical varicose treatment between 2014 and 2017 were examined. Data of patients who underwent foam sclerotherapy with NIR light were collected and analyzed. Results A total of 151 patients and 171 lower extremity varicose veins were treated with surgery. 55 (35.7%) of the patients were male, and 96 (62.3%) were female. Their age ranges from 20 to 64, with an average age of 45.38. 4 (2.6%) of the patients had phlebectomy. 137 of patients (90.7%) had ligation of perforated veins, phlebectomy, and great saphenous vein (GSV) stripping, 10 of patients (6.6%) had GSV stripping, perforating vein ligation, phlebectomy, and small saphenous vein (SSV) surgery. No residual leakage was observed in the controls of GSV, SSV, and perforating veins by duplex ultrasonography (DUS). In the first month after varicose surgery, an average of 1.64 ± 1.05 sessions of sclerotherapy was applied to patients with CEAP C1, C2 stage residual varicose veins. 70 patients had one session of sclerotherapy, 37 patients had two sessions of sclerotherapy, 20 patients had three sessions of sclerotherapy, and 11 patients had four sessions of sclerotherapy administrated. The need for complementary therapy was required for all female patients; 13 of the male patients did not require complementary sclerotherapy. While single-session sclerotherapy was applied to most male patients (32 (58.18%), 10 (18.18%) patients received two sclerotherapy sessions. After completing sclerotherapy, 7 (4.63%) patients had superficial venous thrombosis, and 13 (8.60%) patients had hyperpigmentation. Conclusion Surgical treatment is a safe and effective technique in venous insufficiency. Nevertheless, residual varicose veins may remain, and these can be detected noninvasively with NIR light. Foam sclerotherapy with NIR light is a minimally invasive and safe treatment method for small residual varicose veins after the operation. We think that sclerotherapy with NIR light as a complementary treatment is a practical, reliable, and demanding treatment for clinical improvement, especially in female patients.


Sign in / Sign up

Export Citation Format

Share Document