Article
Chemistry, Analytical
Baha Ondes, Fatma Akpinar, Murat Uygun, Mihrican Muti, Deniz Aktas Uygun
Summary: A highly stable urea biosensor was prepared by immobilizing urease enzyme onto nanoparticles, showing a detection limit of 0.77 mu M and a linear concentration range of 0.01 mM-500 mM. The biosensor system exhibited high repeatability and retained a certain level of activity after long-term storage. Interference from common interferents was found to be negligible, and the biosensor was proven suitable for detecting urea in artificial human serum.
MICROCHEMICAL JOURNAL
(2021)
Article
Engineering, Environmental
Salhah D. Al-Qahtani, Hanan K. Alzahrani, Omer A. Azher, Zeid O. Owidah, Matokah Abualnaja, Turki M. Habeebullah, Nashwa M. El-Metwaly
Summary: A high-sensitivity viscose fabric was developed for colorimetric recognition of urea in fluids using co-encapsulated calcium alginate nanoparticles. Extracted anthocyanin from red-cabbage and urease enzyme were studied for their role in the fabrication of a biosensor on fabrics. The colorimetric changes of the fabric were monitored with increasing urea concentration, showing a shift in absorbance spectra and color variations.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2021)
Article
Engineering, Environmental
Lucas Crane, Hannah Ray, Nasser Hamdan, Treavor H. Boyer
Summary: Enzyme-induced carbonate precipitation (EICP) has the potential to reduce carbon dioxide emissions compared to traditional cementation methods. This study investigated the use of fresh human urine and calcium-rich zeolites as sustainable alternatives for EICP. The results demonstrated that calcium-rich chabazite had higher ammonium adsorption and calcium release capabilities compared to calcium-rich clinoptilolite. The inclusion of a pre-hydrolysis step and longer adsorption times had significant impacts on ammonium adsorption and precipitation outcomes.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2022)
Article
Chemistry, Analytical
Cheol-Kyun Choi, Samy M. Shaban, Byeong-Seok Moon, Do-Gi Pyun, Dong-Hwan Kim
Summary: This study developed a rapid and reliable colorimetric urea biosensor assisted by a smartphone, with high selectivity, sensitivity, and reliability. It enables direct diagnosis of human urine and paves the way for daily monitoring systems of renal and hepatic dysfunction diseases.
ANALYTICA CHIMICA ACTA
(2021)
Article
Polymer Science
Mohamed H. El-Newehy, Hany El-Hamshary, Waheed M. Salem
Summary: Cellulose, a widely-used material, was utilized as a carrier for urease enzyme and tricyanofuran hydrazone to develop a novel fibrous film sensor. The sensor can detect urea visually with rapid response time and low detection limits. The morphology of the nanofibrous films was characterized using various analytical tools, showcasing the successful immobilization of urease enzyme and TCFH onto cellulose nanofibers.
Article
Biotechnology & Applied Microbiology
Marcello Fidaleo, Elisa Tavilli
Summary: This study developed a packed bed immobilized enzyme reactor for removing urea in high polyphenol wines, and immobilization of the enzyme was found to be an effective way to overcome enzyme deactivation caused by phenols, thus enhancing the activity of urease.
FOOD AND BIOPRODUCTS PROCESSING
(2021)
Article
Chemistry, Analytical
Adria Martinez-Avino, Lusine Hakobyan, Ana Ballester-Caudet, Yolanda Moliner-Martinez, Carmen Molins-Legua, Pilar Campins-Falco
Summary: The proposed sensing device utilizes a solid sensing membrane composed of PDMS composite for in situ analysis of ammonia and urea in water and urine samples, with satisfactory strategies applied. Qualitative and quantitative analyte detection is achieved through diffuse reflectance measurements and digital image processing after the colorimetric reaction, showing a linear relationship between sensor response and analyte concentration, and validation through the Berthelot reaction-based thymol-PDMS sensor.
Article
Chemistry, Analytical
Dong Wang, Xiyu Mao, Yitao Liang, Yu Cai, Tingting Tu, Shanshan Zhang, Tianyu Li, Lu Fang, Yue Zhou, Zhaoyang Wang, Yu Jiang, Xuesong Ye, Bo Liang
Summary: Urine analysis is widely used in clinical practice to indicate human health status and diagnose chronic kidney disease (CKD). This study developed NH4+, urea, and creatinine selective electrodes for urine analysis, achieving good selectivity, consistency, and stability. Integration into a paper-based device allowed for point-of-care testing using real human urine samples. This multi-parameter urine testing device has the potential to efficiently manage CKD.
Article
Biochemistry & Molecular Biology
Laszlo Kook, Kristof Bence Nagy, Ilona Nyiro-Kosa, Szilveszter Kovacs, Jan Zitka, Miroslav Otmar, Peter Bakonyi, Nandor Nemestothy, Katalin Belafi-Bako
Summary: This study aims to simultaneously recover urea and phosphorous from synthetic urine using electrochemical pH modulation. Urea was stabilized by the in situ formation of OH- ions at the cathode. The precipitation of phosphorous with divalent cations (Ca2+, Mg2+) during pH elevation was also investigated. Results showed that urea could be successfully stabilized for over 1 month at pH 11.5, and over 82% phosphorous recovery could be achieved in the form of amorphous calcium magnesium phosphate (CMP) precipitate.
Article
Chemistry, Multidisciplinary
Nur Izzati Zakaria, Rosmawani Mohammad, Sharina Abu Hanifah, Azrilawani Ahmad
Summary: In this study, an optical biosensor for urea based on functionalised calcium carbonate nanoparticles was successfully developed. The biosensor showed a colorimetric indication of urea concentrations and had a wide linear response range, low detection limit, good reproducibility, and no interference from major cations. The fabricated biosensor demonstrated no significant difference with the standard method for urea determination in urine samples.
ARABIAN JOURNAL OF CHEMISTRY
(2022)
Review
Environmental Sciences
Marta Klimczyk, Anna Siczek, Lech Schimmelpfennig
Summary: The addition of urease inhibitor NBPT to urea fertilizers can reduce ammonia emissions, while nitrification inhibitors may lead to an increase in ammonia emission. Factors such as dose and date of application, method of application, type of soil and pH, as well as atmospheric conditions, also have an impact on ammonia emissions.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Chemistry, Multidisciplinary
Amrish Prabakaran, Bahrudeen Shahul Hameed, K. S. Shalini Devi, Uma Maheswari Krishnan
Summary: A promising electrochemical biosensor was developed for the direct detection of urea, utilizing urease enzyme and a nanointerface consisting of gold nanoparticle decorated Prussian blue nanocubes and multi-walled carbon nanotubes. The sensor showed a linear sensing range between 1 and 10 mM urea concentration with a response time of 20 s at 0.2 V vs. Ag/AgCl, and has a detection limit and sensitivity values of 0.32 mM and 0.108 mu A/mM, respectively. The biosensor demonstrated good selectivity and was validated with rat blood serum.
Article
Polymer Science
Natalia Guerrero-Alburquerque, Shanyu Zhao, Daniel Rentsch, Matthias M. Koebel, Marco Lattuada, Wim J. Malfait
Summary: Urea, as an alternative to KOCN, shows potential for grafting ureido groups onto amines in aqueous media due to its low cost, non-toxicity, and biocompatibility. Reaction times are almost independent of substrate and pH, but excess urea is required for practically feasible reaction rates.
Article
Chemistry, Analytical
Farzaneh Shalileh, Hossein Sabahi, Mohammad Golbashy, Mehdi Dadmehr, Morteza Hosseini
Summary: A novel colorimetric paper-based urea biosensor was developed for the rapid and accurate detection of urea adulteration in milk. The biosensing mechanism relies on the color change of anthocyanin due to the urease-mediated hydrolysis of urea and pH increment. The biosensor showed promising results for the detection of urea in milk samples, even in the presence of other adulterants and interferents.
ANALYTICA CHIMICA ACTA
(2023)
Article
Multidisciplinary Sciences
Tuser T. Biswas, Junchun Yu, Vincent A. Nierstrasz
Summary: In this study, tyrosinase enzyme was digitally printed on plasma pretreated polyamide-6,6 fabric using sustainable technologies. Ink containing carboxymethyl cellulose was found to be the most suitable viscosity modifier for the enzyme. The printed enzyme on the fabric surface retained a high level of activity even after multiple rinsing cycles. The printed fabrics showed more stable enzyme activity compared to the ink solution for at least 60 days. This research demonstrates the potential applications of tyrosinase printed synthetic fabrics in various fields.
SCIENTIFIC REPORTS
(2022)
Article
Multidisciplinary Sciences
Mingtong Li, Yichao Tang, Ren Hao Soon, Bin Dong, Wenqi Hu, Metin Sitti
Summary: Wireless small-scale soft actuators, utilizing the interactions between coiled artificial muscle and radio frequency-magnetic heating, have been developed to address the constraints of current miniature soft actuators. These wirelessly controlled actuators exhibit a large output force and high work capacity, and can be designed into various functional devices for minimally invasive medical applications.
Article
Multidisciplinary Sciences
Ren Hao Soon, Ziyu Ren, Wenqi Hu, Ugur Bozuyuk, Erdost Yildiz, Meng Li, Metin Sitti
Summary: This article presents a wireless spring-preloaded barbed needle release mechanism for anchoring untethered soft miniature robots. The mechanism is wirelessly triggered using radio-frequency remote heating and can be easily integrated into existing robotic platforms. It provides robust anchoring in biological tissues and extends the operating depth of the device inside the body. This mechanism opens up new possibilities for biomedical functionalities in untethered soft medical robots.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Chemistry, Multidisciplinary
Yufeng Shou, Xin Yong Teo, Xianlei Li, Zhicheng Le, Ling Liu, Xinhong Sun, Win Jonhson, Jun Ding, Chwee Teck Lim, Andy Tay
Summary: This study developed a dynamic 3D magnetic hydrogel that can wirelessly and reversibly change its matrix stiffness multiple times using an external magnet, enabling the study of the impact of matrix softening on cancer biology. It was found that increasing matrix stiffness promotes tumor malignancy, but the malignant transformations can be halted or reversed by matrix softening, enhancing drug efficacy.
Article
Chemistry, Multidisciplinary
Shuwen Chen, Shicheng Fan, Jiaming Qi, Ze Xiong, Zheng Qiao, Zixiong Wu, Joo Chuan Yeo, Chwee Teck Lim
Summary: A bilayer liquid-solid conductor (b-LSC) with amphiphilic properties is introduced in this study to interface reliably with both rigid electronics and elastomeric substrates. It exhibits high strain-insensitive conductivity, extreme stretchability, and negligible resistance change under ultra-high strain. The b-LSC can be used for various applications, such as stretchable sensor arrays, multi-layered stretchable displays, and highly integrated haptic user-interactive optoelectric E-skins.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Analytical
Huanqian Zhang, Jee Chin Teoh, Jianfeng Wu, Longteng Yu, Chwee Teck Lim
Summary: One advantage of a resistive sensor array (RSA) with shared rows and shared columns is the reduced number of wires, which can lessen the complexity and burden on wearable electronic systems. However, the drawback is the crosstalk current effect between adjacent elements, which leads to high measurement error. This study introduces a new circuit design called the dynamic zero current method (DZCM) to decrease the measurement error further.
Article
Engineering, Biomedical
Hardik Makkar, Ying Zhou, Kai Soo Tan, Chwee Teck Lim, Gopu Sriram
Summary: Gingival crevice and gingival crevicular fluid (GCF) flow are crucial for maintaining gingival health and preventing periodontal disease. However, current in vitro models lack the dynamic nature of the gingival crevicular microenvironment, hindering the development of periodontal therapeutics. This study describes a microfluidic platform that mimics GCF flow to culture gingival connective tissue. The platform successfully replicated microbial colonization, biofilm formation, and early gingival inflammation in response to oral symbiont and periodontal pathogen exposure. The induction of flow attenuated the secretion of inflammatory mediators, demonstrating the protective effect of GCF flow.
ADVANCED HEALTHCARE MATERIALS
(2023)
Article
Engineering, Electrical & Electronic
Shuaikang Gao, Qi Wang, Longteng Yu
Summary: This article presents a novel approach to object recognition based on surface properties, called multimodal tactile perception. By modifying the fingertips of a five-fingered robotic hand, hardness and texture perception are achieved through the attachment of a rigid indenter and a glass bead on the thumb and index finger respectively. After processing the data using fast Fourier transform and principal component analysis, machine learning algorithms such as multilayer perceptron and support vector machines are used to identify objects based on hardness and texture. The online experiment demonstrates an accuracy of 86.0% in distinguishing seven different toys. This work provides a quick solution for object recognition using force sensors in humanoid robots.
IEEE SENSORS LETTERS
(2023)
Article
Multidisciplinary Sciences
Ren Hao Soon, Zhen Yin, Metin Alp Dogan, Nihal Olcay Dogan, Mehmet Efe Tiryaki, Alp Can Karacakol, Asli Aydin, Pouria Esmaeili-Dokht, Metin Sitti
Summary: This article presents a pangolin-inspired bi-layered soft robot design that achieves heating >70 degrees C at distances >5cm without compromising compliance and safety, thus providing a new option for biomedical applications.
NATURE COMMUNICATIONS
(2023)
Article
Nanoscience & Nanotechnology
Y. Belotti, D. S. Jokhun, V. L. M. Valerio, T. W. Chong, C. T. Lim
Summary: We developed a fast and cost-effective method that combines pH imaging and machine learning for non-invasive identification of different cell populations at the single-cell level. By leveraging biophysical and biochemical markers obtained from pH imaging with deep learning, we achieved highly accurate classification of cancer cells.
Review
Nanoscience & Nanotechnology
Christy Kwokdinata, Vaibavi Ramanujam, Jiahui Chen, Paula Nunes de Oliveira, Mui Hoon Nai, Wai Hon Chooi, Chwee Teck Lim, Shi Yan Ng, Laurent David, Sing Yian Chew
Summary: This study found that using injectable hyaluronan-gelatin hydrogel in transplantation therapy can promote cell survival and neural differentiation of human spinal cord progenitor cells.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Engineering, Biomedical
Hardik Makkar, Chwee Teck Lim, Kai Soo Tan, Gopu Sriram
Summary: Gingival connective tissue and its vasculature are important for the immune response against oral bacteria and act as a connection between the oral and systemic environments. However, there's a lack of models that mimic the complex features of vascularized gingival connective tissue and its interaction with oral bacteria, limiting our understanding of periodontal health and disease. In this study, the researchers developed vascularized gingival tissue models to study the interactions between oral bacteria and gingival tissues in different states. They found that different oral bacteria had different effects on the tissue, with some leading to disease symptoms. The models also showed potential for studying periodontitis and vascular diseases. Overall, the vascularized gingival tissue models provide an in vitro platform for studying host-microbiome interactions and immune response in periodontal health and disease, and may contribute to the development of new periodontal therapeutics.
Article
Chemistry, Multidisciplinary
Jiaming Qi, Feng Gao, Guanghui Sun, Joo Chuan Yeo, Chwee Teck Lim
Summary: To enhance the realism and immersion of human-computer interaction, novel haptics technologies are developed to bridge the gap between the physical world and digital environment. The HaptGlove, an untethered and lightweight pneumatic glove, allows users to physically interact in a VR environment, providing natural and realistic kinesthetic and cutaneous sensations. Through a user study, significant improvements in VR realism and immersion are observed, with participants achieving 78.9% accuracy in sorting virtual objects of different stiffnesses. Importantly, HaptGlove facilitates VR training, education, entertainment, and socialization.
Article
Automation & Control Systems
Yao Tang, Longteng Yu, Jing Pan, Ni Yao, Weidong Geng, Xiong Li, Limin Tong, Lei Zhang, Zhengyou Zhang, Aiguo Song
Summary: Soft, flexible, thin, and multimodal robotic skins are achieved by embedding lab-made optical nanofibers into elastomeric films. These skins have low flexural rigidity and large evanescent field, thanks to the subwavelength diameters of the nanofibers. Variable sensitivities and sensing ranges for both force and temperature can be achieved by tuning the light wavelength, nanofiber diameter, and skin thickness. These optical nanofiber skins have the potential to be used in various intelligent systems, including robotics, prosthetics, human-machine interface, and wearable devices.
ADVANCED INTELLIGENT SYSTEMS
(2023)
Review
Chemistry, Multidisciplinary
Shuwen Chen, Shicheng Fan, Henryk Chan, Zheng Qiao, Jiaming Qi, Zixiong Wu, Joo Chuan Yeo, Chwee Teck Lim
Summary: Flexible wearable devices and medical robotics are crucial for smart healthcare. Liquid metal materials have emerged as key elements for these innovations. This review discusses the latest breakthroughs in liquid metal functionalization and their applications in healthcare-related wearables and soft robotics.
ADVANCED FUNCTIONAL MATERIALS
(2023)
