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Locating remedies for Alzheimer’s disease (AD) has been majorly restricted by the inefficiency to establish a definitive detection model for early-stage diagnosis of pathological events. This current lapse in AD diagnosis also limits the therapeutic efficiency of the drugs, which might have been effective if given at the earlier stages of the disease. The indicated situation directs towards the burgeoned need for an effective biomarker technique that will help in early detection of AD and would be imminently useful to facilitate improved diagnosis and stimulate therapeutic trials. Till date, the major biomarkers, specifically associated with AD detection, may help in determining the early-stage AD diagnosis and identifying alterations in the cellular proteome, offering deeper insight into disease etiology. Currently existing multidisciplinary clinical diagnosis of AD is a very tedious, expensive procedure and requires highly trained and skilled professionals who are rarely available outside the specialty clinics. Mutations in amyloid precursor protein (APP) or Presenilin 1 and 2 (PSEN1 and PSEN2) are some biomarkers acting as critical checkpoints for AD diagnosis. However, the presence of some associated biomarkers in cerebrospinal fluid (CSF) such as total-Tau (tTau), phosphorylated- Tau (pTau) 181 and Amyloid-β (Aβ) 1-42 using structural or functional imaging techniques is considered for confirmatory diagnosis of AD. Furthermore, the molecular diagnosis of AD incorporates various sophisticated techniques including immuno-sensing, machine learning, nano conjugation-based detections, etc. In the current review description, we have summarized the various diagnostic approaches and their relevance in mitigating the long-standing urgency of targeted diagnostic tools for detection of AD.

Release of cargo molecules from cell-like nanocarriers can be achieved by chemical perturbations, including changes to pH and redox state and viaoptical modulation of membrane properties. However, little is known about the kinetics or products of vesicle breakdown due to limitations in real-time imaging at nanometer length scales. Using a library of 12 single–single type photocleavable amphiphilic Janus dendrimers, we developed a self-assembling light-responsive dendrimersome vesicle platform. A photocleavable ortho-nitrobenzyl inserted between the hydrophobic and hydrophilic dendrons of amphiphilic Janus dendrimers allowed for photocleavage and disassembly of their supramolecular assemblies. Distinct methods used to self-assemble amphiphilic Janus dendrimers produced either nanometer size small unilamellar vesicles or micron size giant multilamellar and onion-like dendrimersomes. In situobservation of giant photosensitive dendrimersomes viaconfocal microscopy elucidated rapid morphological transitions that accompany vesicle breakdown upon 405 nm laser illumination. Giant dendrimersomes displayed light-induced cleavage, disassembling and reassembling into much smaller vesicles at millisecond time scales. Additionally, photocleavable vesicles demonstrated rapid release of molecular and macromolecular cargos. These results guided our design of multilamellar particles to photorelease surface-attached proteins, photoinduce cargo recruitment, and photoconvert vesicle morphology. Real-time characterization of the breakdown and reassembly of lamellar structures provides insights on partial cargo retention and informs the design of versatile, optically regulated carriers for applications in nanoscience and synthetic biology.

In recent times, several approaches for targeted gene therapy (GT) had been studied. However, the emergence of extracellular vesicles (EVs) as a shuttle carrying genetic information between cells has gained a lot of interest in scientific communities. Owing to their higher capabilities in dealing with short sequences of nucleic acid (mRNA, miRNA), proteins, recombinant proteins, exosomes, the most popular form of EVs are viewed as reliable biological therapeutic conveyers. They have natural access through every biological membrane and can be employed for site-specific and efficient drug delivery without eliciting any immune responses hence, qualifying as an ideal delivery vehicle. Also, there are many research studies conducted in the last few decades on using exosome-mediated gene therapy into developing an effective therapy with the concept of a higher degree of precision in gene isolation, purification and delivery mechanism loading, delivery and targeting protocols. This review discusses several facets that contribute towards developing an efficient therapeutic regime for gene therapy, highlighting limitations and drawbacks associated with current GT and suggested therapeutic regimes.