Carbon-Based Nanobiohybrid Thin Film for Amperometric Glucose Sensing

Potential Environmental and Health Implications from the Scaled-Up Production and Disposal of Nanomaterials Used in Biosensors

Biosensors often combine biological recognition elements with nanomaterials of varying compositions and dimensions to facilitate or enhance the operating mechanism of the device. While incorporating nanomaterials is beneficial to developing high-performance biosensors, at the stages of scale-up and disposal, it may lead to the unmanaged release of toxic nanomaterials. Here we attempt to foster connections between the domains of biosensors development and human and environmental toxicology to encourage a holistic approach to the development and scale-up of biosensors. We begin by exploring the toxicity of nanomaterials commonly used in biosensor design. From our analysis, we introduce five factors with a role in nanotoxicity that should be considered at the biosensor development stages to better manage toxicity. Finally, we contextualize the discussion by presenting the relevant stages and routes of exposure in the biosensor life cycle. Our review found little consensus on how the factors presented govern nanomaterial toxicity, especially in composite and alloyed nanomaterials. To bridge the current gap in understanding and mitigate the risks of uncontrolled nanomaterial release, we advocate for greater collaboration through a precautionary One Health approach to future development and a movement towards a circular approach to biosensor use and disposal.

Fabrication of 2D-MoSe2 incorporated NiO Nanorods modified electrode for selective detection of glucose in serum samples

Layered molybdenum diselenide (MoSe2) nanosheets were formed by the weak Van der Waals forces of attraction between Se and Mo atoms. MoSe2 has a larger space between the adjacent layers and smaller band gaps in the range of 0.85 to ~ 1.6 eV. In this study, MoSe2 nanosheets decorated nickel oxide (NiO) nanorods have been synthesized by hydrothermal method using sodium molybdate and selenium metal powder. NiO/MoSe2 composite formation was confirmed by powder X-ray diffraction analysis. In addition, the presence of MoSe2 nanosheets on NiO nanorods were confirmed by field emission scanning electron microscopy, high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy. The Nyquist plots of NiO/MoSe2 coated glassy carbon electrode (GCE) was indicated that it had lower charge transfer resistance compared to NiO/GCE and MoSe2/GCE. Furthermore, as-prepared NiO/MoSe2/GCE was used to detect glucose in alkaline solution by cyclic voltammetry and amperometry techniques. The NiO/MoSe2/GCE was exhibited a linear response for the oxidation of glucose from 50 µM to 15.5 mM (R2 = 0.9842) at 0.5 V by amperometry. The sensor response time and the limit of detection were found to be 2 s and 0.6 µM for glucose. Moreover, selectivity of the NiO/MoSe2 sensor was tested in the presence of common interferent molecules such as hydrogen peroxide, fructose, lactose, ascorbic acid, uric acid, and dopamine. It was found that NiO/MoSe2/GCE did not respond to these interfering biomolecules. In addition, NiO/MoSe2/GCE had shown high stability, reproducibility and repeatability. Finally, the practical application of the sensor was demonstrated by detecting glucose in human blood serum with the acceptable recovery.

Plate-like hydroxyapatite synthesized from dodecanedioic acid enhances chondrogenic cell proliferation

BACKGROUND

The scaffold for head and neck reconstruction needs mechanical strength to maintain specific forms. Hydroxyapatite (HA) enhances the mechanical strength of hydrogel and is routinely used for cartilage regeneration. However, there is a demand for hydroxyapatite that controls chondrogenic cell behavior.

OBJECTIVE

Our aim was to regulate HA morphology through a hydrothermal process using organic acid and enhance chondrocyte proliferation and differentiation using shaped-regulated HA.

METHODS

HA was synthesized from dodecanedioic acid (DD:HA) and oleic acid (OA:HA) by a hydrothermal method and then coated onto glass plates. Surface properties of the samples were compared by various techniques. Surface roughness and contact angles were calculated. Proliferation and differentiation of chondrogenic cells were measured by MTT assays and Alcian Blue staining, respectively, after various incubation periods.

RESULTS

The morphological structures of DD:HA and OA:HA were different; however, the crystallinity and chemical structures were similar. Surface roughness and hydrophilic behavior were higher on DD:HA. DD:HA enhanced chondrogenic cell proliferation over time. The differentiation of ATDC5 cells was also increased on the DD:HA surface compared with those in other groups.

CONCLUSIONS

DD:HA enhanced cell viability to a greater extent than OA:HA did, indicating its excellent potential as an inorganic material compatible with chondrocyte regeneration.