Bacterial cellulose (BC), with non-toxicity, high purity, and biocompatibility, has been considered as a versatile candidate for various biomedical applications. Recently, the fabrication of BC-based composite scaffolds compounded with other ingredients such as nanoparticles and polymers has received extensive investigation, which enabled the development of numerous promising biomedical products. Additionally, BC-derived nanocrystals (BCNCs) and nanofibrils (BCNFs) have proven to be promising reinforcing agents in a variety of polymeric scaffolds for biomedical applications. In this review, we summarize recent preparation strategies for BC-based and BCNCs- and BCNFs-containing composite scaffolds and their advances in biomedical applications, including wound healing, tissue engineering, and drug delivery, as well as tumor cell culture and cancer treatment. Finally, we present challenges and future perspectives for BC-based composite scaffolds for biomedical applications.

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Since the first discovery of polyacetylene in the late 1970s, the one-dimensional (1D) conjugated polymers have attracted immense research interest as a result of their high conductivity, wide and tunable...

Rapid and effective differentiation and quantification of a small molecule drug, such as fentanyl, in bodily fluids are major challenges for diagnosis and personal medication. However, the current toxicology methods used to measure drug concentration and metabolites require laboratory-based testing, which is not an efficient or cost-effective way to treat patients in a timely manner. Here, we show an assay for monitoring fentanyl levels by combining the intermolecular interaction-enabled small molecule recognition (iMSR) with differential impedance analysis of conjugated polymers. The differential interactions with the designed anchor interface were transduced through the perturbance of the electric status of the flexible conducting polymer. This assay showed excellent fentanyl selectivity against common interferences, as well as in variable body fluids through either testing strips or skin patches. Directly using the patient blood, the sensor provided 1%–5% of the average deviation compared to the “gold” standard method LC-MS results in the medically relevant fentanyl range of 20–90 nM. The superior sensing properties, in conjunction with mechanical flexibility and compatibility, enabled point-of-care detection and provided a promising avenue for applications beyond the scope of biomarker detection.

A flexible resistive-type polyaniline-based gas sensor was fabricated by simple dip-coating of graphene combined with in situ polymerization of aniline on a flexible waste mask substrate. The prepared polypropylene/graphene/polyaniline (PP/G/PANI) hybrid sensor demonstrated a fast response (114 s) and recovery time (23 s), ppb-level detection limit (100 ppb), high response value (250% toward 50 ppm NH3, which is over four times greater than that of the pristine PANI sensor), acceptable flexibility, excellent selectivity, and long-term stability at room temperature. The morphological and structural properties of the composite sensor materials were characterized by scanning electron microscopy and energy-dispersive spectroscopy characterization, and the surface chemistry of the hybrid sensors was analyzed by Fourier transform infrared spectroscopy. The excellent sensing performance was mainly ascribed to the larger specific surface area and efficient conducting paths of the porous PP/G/PANI network. Moreover, the PP/G/PANI hybrid gas sensor exhibited excellent sensing capability on volatile sulfur compounds contained in human breath, indicating that the hybrid sensor can be applied to breath analysis and kidney disease diagnosis.