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Abstract Introduction Visual assessment and imaging of the donor liver are inaccurate in predicting fibrosis and remain surrogates for histopathology. We demonstrate that 3‐s scans using a handheld near‐infrared‐spectroscopy (NIRS) instrument can identify and quantify fibrosis in fresh human liver samples. Methods We undertook NIRS scans on 107 samples from 27 patients, 88 from 23 patients with liver disease, and 19 from four organ donors. Results Liver disease patients had a median immature fibrosis of 40% (interquartile range [IQR] 20–60) and mature fibrosis of 30% (10%–50%) on histopathology. The organ donor livers had a median fibrosis (both mature and immature) of 10% (IQR 5%–15%). Using machine learning, this study detected presence of cirrhosis and METAVIR grade of fibrosis with a classification accuracy of 96.3% and 97.2%, precision of 96.3% and 97.0%, recall of 96.3% and 97.2%, specificity of 95.4% and 98.0% and area under receiver operator curve of 0.977 and 0.999, respectively. Using partial‐least square regression machine learning, this study predicted the percentage of both immature (R2 = 0.842) and mature (R2 = 0.837) with a low margin of error (root mean square of error of 9.76% and 7.96%, respectively). Conclusion This study demonstrates that a point‐of‐care NIRS instrument can accurately detect, quantify and classify liver fibrosis using machine learning.

Biomedical electronic implants require a power source to operate. Miniaturised implants can preclude batteries and as implant dimensions reduce further, inductive power transfer no longer becomes the optimum strategy for wireless power delivery. Wide dipole antennas are proposed as an alternative power transmitter for long and thin implants. A miniaturised bioelectronic device measuring 1 mm by 1 mm by 20 mm was fabricated, wirelessly powered and used to stimulate retinal ganglion cells to provide biological validation of its functionality. Optimised wide dipole antennas operating in the GHz range for implant depths of 5 mm to 35 mm in 5 mm steps were simulated, fabricated and measured. Saline solution was used as a biological tissue phantom for power transfer efficiency measurements. The maximum safe deliverable power to the device was 1.7 mW in simulation and 1.3 mW in measurement at power transfer efficiencies of 15% and 11% respectively. The work herein confirms that wide dipole transmitting antennas are suitable for radiative near field power transfer to long and thin implants. This power transfer technique could be used for implants that are injectable, deliverable via catheter and minimally invasive, advancing the aim to create smaller more innovative electronic implantable devices. Keywords: Wireless power transfer, Bioelectronics, Antennas, Retinal ganglion cells, Injectable, Biological tissue, Finite element method