A portable micro-nanochannel bio-3D printed liver microtissue biosensor for DON detection.

We investigated a portable micro-nanochannel biosensor 3D-printed liver microtissues for rapid and sensitive deoxynivalenol (DON) detection. The screen-printed carbon electrode (SPCE) was modified with nanoporous anodic aluminum oxide (AAO), gold nanoparticles (AuNPs), and cytochrome C oxidase (COx) to enhance sensor performance. Gelatin methacrylate hydrogel, combined with hepatocellular carcinoma cells, formed the bioink for 3D printing. Liver microtissues were prepared through standardized and high-throughput techniques via bio-3D printing technology. These microtissues were immobilized onto modified electrodes to fabricate liver microtissue sensors. The peak current of this biosensor was positively correlated with DON concentration, as determined by cyclic voltammetry (CV), within a linear detection range of 2∼40 µg/mL. The standard curve equation is denoted by ICV(µA) = = 18.76956 + 0.03107CDON(µg/mL), with a correlation coefficient R2 was 0.99471(n＝3). A minimum detection limit of 1.229 µg/mL was calculated from the formula, indicating the successful construction of a portable micro-nanochannel bio-3D printed liver microtissue biosensor. It provides innovative ideas for developing rapid and convenient instrumentation to detect mycotoxin hazards after grain production. It also holds significant potential for application in the prediction and assessment of post-production quality changes in grain.

3D bio-printing-based vascular-microtissue electrochemical biosensor for fish parvalbumin detection.

A novel 3D bio-printing vascular microtissue biosensor was developed to detect fish parvalbumin quickly. The graphite rod electrode was modified with gold and copper organic framework (Cu-MOF) to improve the sensor properties. Polydopamine-modified multi-wall carbon nanotubes (PDA-MWCNT) were mixed with gelatin methacryloyl (GelMA) to prepare a conductive hydrogel. The conductive hydrogel was mixed with mast cells and endothelial cells to produce a bio-ink for 3D bioprinting. High throughput and standardized preparation of vascular microtissue was performed by stereolithography 3D bioprinting. The vascular microtissue was immobilized on the modified electrode to construct the microtissue sensor. The biosensor's peak current was positively correlated with the fish parvalbumin concentration, and the detection linear concentration range was 0.1 ∼ 2.5 µg/mL. The standard curve equation was IDPV(µA) = 31.30 + 5.46 CPV(µg/mL), the correlation coefficient R2 was 0.990 (n = 5), and the detection limit was 0.065 µg/mL. These indicated a biomimetic microtissue sensor detecting fish parvalbumin has been successfully constructed.

A novel 3D bio-printing "liver lobule" microtissue biosensor for the detection of AFB1.

In this paper, a novel "liver lobule" microtissue biosensor based on 3D bio-printing is developed to rapidly determine aflatoxin B1 (AFB1). Methylacylated Hyaluronic acid (HAMA) hydrogel, HepG2 cells, and carbon nanotubes are used to construct "liver lobule" models. In addition, 3D bio-printing is used to perform high-throughput and standardized preparation in order to simulate the organ morphology and induce functional formation. Afterwards, based on the electrochemical rapid detection technology, a 3D bio-printed "liver lobule" microtissue is immobilized on the screen-printed electrode, and the mycotoxin is detected by differential pulse voltammetry (DPV). The DPV response increases with the concentration of AFB1 in the range of 0.1-3.5 µg/mL. The linear detection range is 0.1-1.5 µg/mL and the calculated lowest detection limit is 0.039 µg/mL. Thus, this study develops a new mycotoxin detection method based on the 3D printing technology, which has high stability and reproducibility. It has wide application prospects in the field of detection and evaluation of food hazards.