The imine of polybenzimidazole (PBI) is chemically oxidized by hydrogen peroxide (H(2)O(2)) in the presence of acetic acid (AcOH). Fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopies (XPS) showed that when the AcOH concentration remained constant, the degree of oxidation increased with increasing H(2)O(2) levels. Moreover, the imine also exhibited electrochemical redox behavior. Based on these properties, a PBI-modified Au (PBI/Au) electrode was developed as an enzyme-free H(2)O(2) sensor. At an applied potential of -0.5V vs. Ag/AgCl, the current response of the PBI/Au electrode was linear with H(2)O(2) concentration over a range from 0.075 to 1.5mM, with a sensitivity of 55.0 μA mM(-1)cm(-2). The probe had excellent stability, with <5% variation from its initial response current after storage at 50°C for 10 days. Potentially interfering species such as ascorbic or uric acid had no effect on sensitivity. Sensitivity improved dramatically when multiwalled carbon nanotubes (MWCNT) were incorporated in the probe. Under optimal conditions, the detection of H(2)O(2) using a MWCNT-PBI/Au electrode was linear from 1.56 μM to 2.5mM, with a sensitivity of 928.6 μA mM(-1)cm(-2). Analysis of H(2)O(2) concentrations in urine samples using a MWCNT-PBI/Au electrode produced accurate real-time results comparable to those of traditional HPLC methods.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.talanta.2011.04.038 | DOI Listing |
Braz J Microbiol
January 2025
ICAR - Indian Veterinary Research Institute, Bengaluru, 560 024, Karnataka, India.
Developing an effective vaccine for haemorrhagic septicaemia (HS) in cattle and buffaloes is urgently needed. While preferred for their safety, achieving sufficient, cross-protective, and long-lasting immunity is still challenging when administering inactivated vaccines. This study aimed to assess the efficacy of four inactivating components comprising three inactivating agents: (1) Binary ethylenimine (BEI), (2) Formalin, (3) a combination of BEI and Formalin, and (4) Hydrogen peroxide (HO), in inactivating Pasteurella multocida to enhance HS vaccine potency.
View Article and Find Full Text PDFMikrochim Acta
January 2025
Department of Chemistry, School of Science, Xihua University, Chengdu, 610039, PR China.
Based on the enhanced peroxidase-like activity of carbon dots nanozymes (CDszymes), with a specific oxidation reaction of D-amino acid oxidase catalysing the formation of HO from D-amino acid, an ultrasensitive sensing platform, was constructed for the quantitative detection of D-amino acids in saliva. With the increase of D-amino acids concentration, the blue color of catalytic product gradually deepend, the fluorescence CDszymes gradually quenched, and the temperature gradually increased. Using D-alanine as D-amino acid models, the detection limits of D-alanine in colorimetric/photothermal/fluorescent mode were 0.
View Article and Find Full Text PDFAdv Healthc Mater
January 2025
National and Local Joint Engineering Research Center of Biomedical Functional Materials, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, 210023, China.
Bacterial infections can lead to severe medical complications, including major medical incidents and even death, posing a significant challenge in clinical trauma repair. Consequently, the development of new, efficient, and non-resistant antimicrobial agents has become a priority for medical practitioners. In this study, a stepwise hydrothermal reaction strategy is utilized to prepare FeO@MoS core-shell nanoparticles (NPs) with photosynthesis-like activity for the treatment of bacterial infections.
View Article and Find Full Text PDFRSC Adv
January 2025
Environmental Biotechnology Laboratory, Department of Biological Sciences, Birla Institute of Technology and Science Pilani, Hyderabad Campus, Jawahar Nagar, Kapra Mandal, Medchal District Hyderabad 500078 India
Cow milk is readily adulterated due to its complex properties that can emulsify many adulterants. Among the commonly used adulterants in cow milk are hydrogen peroxide (HP) and nitrite. Commercially available HP is added to extend cow milk's shelf life, while nitrite enters through the tap or pond water added to increase cow milk's volume.
View Article and Find Full Text PDFFront Bioeng Biotechnol
January 2025
Department of Experimental Research and Guangxi Cancer Molecular Medicine Engineering Research Center and Guangxi Key Laboratory of Basic and Translational Research for Colorectal Cancer, Guangxi Medical University Cancer Hospital, Nanning, China.
An emerging strategy in cancer therapy involves inducing reactive oxygen species (ROS), specifically within tumors using nanozymes. However, existing nanozymes suffer from limitations such as low reactivity, poor biocompatibility, and limited targeting capabilities, hindering their therapeutic efficacy. In response, the PdRu@PEI bimetallic nanoalloys were constructed with well-catalytic activities and effective separation of charges, which can catalyze hydrogen peroxide (HO) to toxic hydroxyl radical (·OH) under near-infrared laser stimulation.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!