A remarkable progress in the development of portable paper-based biosensors (PBBs) and microfluidic paper-based analytical devices (μPADs) has recently been achieved. In these devices, a paper formed of microfibers of cellulose, a carbohydrate biopolymer, offers both an ample space in its micropores for analytical reagents storage and a capillary force to drive liquid samples to a dedicated reaction zone for instantaneous detection of the desired analytes. Owing to the low cost and ultra-high sensitivity, these novel devices have become a promising alternative to traditional advanced analytical instruments and offer great potential for applications in medical emergencies, health diagnostics at points-of-care, and broad early-cancer screening. In this review, we focus particularly on recent important achievements in utilization of cellulose and its modifications in portable sensing devices for biomedical applications. The progress in functionalization of cellulose papers with antibodies, nucleic acids and nanomaterials in PBBs and μPADs, is discussed and critically evaluated.

Neurodegenerative diseases (NDs) are a diverse group of disorders characterized by the progressive degeneration and death of neurons, leading to a range of neurological symptoms. Despite the heterogeneity of these conditions, a common denominator is the implication of mitochondrial dysfunction in their pathogenesis. Mitochondria play a crucial role in creating biomolecules, providing energy through adenosine triphosphate (ATP) generated by oxidative phosphorylation (OXPHOS), and producing reactive oxygen species (ROS). When they’re not functioning correctly, becoming fragmented and losing their membrane potential, they contribute to these diseases. In this review, we explore how mitochondria fuse and undergo fission, especially in the context of NDs. We discuss the genetic and protein mutations linked to these diseases and how they impact mitochondrial dynamics. We also look at the key regulatory proteins in fusion (MFN1, MFN2, and OPA1) and fission (DRP1 and FIS1), including their post-translational modifications. Furthermore, we highlight potential drugs that can influence mitochondrial dynamics. By unpacking these complex processes, we aim to direct research towards treatments that can improve life quality for people with these challenging conditions.