Nanotechnologies meeting natural sources:Engineered lipoproteins for precise brain disease theranostics

Biological nanotechnologies have provided considerable opportunities in the management of malignancies with delicate design and negligible toxicity,from preventive and diagnostic to therapeutic fields.Lipoproteins,because of their inherent blood-brain barrier permeability and lesion-homing capability,have been identified as promising strategies for high-performance theranostics of brain diseases.However,the application of natural lipoproteins remains limited owing to insufficient accumulation and complex purification processes,which can be critical for individual therapeutics and clinical translation.To address these issues,lipoprotein-inspired nano drug-delivery systems(nano-DDSs),which have been learned from nature,have been fabricated to achieve synergistic drug delivery involving site-specific accumulation and tractable preparation with versatile physicochemical functions.In this review,the barriers in brain disease treatment,advantages of state-of-the-art lipoprotein-inspired nano-DDSs,and bio-interactions of such nano-DDSs are highlighted.Furthermore,the characteristics and advanced applications of natural lipoproteins and tailor-made lipoprotein-inspired nano-DDSs are summarized.Specifically,the key designs and current applications of lipoprotein-inspired nano-DDSs in the field of brain disease therapy are intensively discussed.Finally,the current challenges and future perspectives in the field of lipoprotein-inspired nano-DDSs combined with other vehicles,such as exosomes,cell membranes,and bacteria,are discussed.

Nano-enabled cellular engineering for bioelectric studies

Engineered cells have opened up a new avenue for scientists and engineers to achieve specialized biological functions.Nanomaterials,such as silicon nanowires and quantum dots,can establish tight interfaces with cells either extra-or intracellularly,and they have already been widely used to control cellular functions.The future exploration of nanomaterials in cellular engineering may reveal numerous opportunities in both fundamental bioelectric studies and clinic applications.In this review,we highlight several nanomaterials-enabled non-genetic approaches to fabricating engineered cells.First,we briefly review the latest progress in engineered or synthetic cells,such as protocells that create cell-like behaviors from nonliving building blocks,and cells made by genetic or chemical modifications.Next,we illustrate the need for non-genetic cellular engineering with semiconductors and present some examples where chemical synthesis yields complex morphology or functions needed for biointerfaces.We then provide discussions in detail about the semiconductor nanostructure-enabled neural,cardiac,and microbial modulations.We also suggest the need to integrate tissue engineering with semiconductor devices to carry out more complex functions.We end this review by providing our perspectives for future development in non-genetic cellular engineering.