Sweat-Based in Vitro Diagnostics(IVD):From Sample Collection to Point-of-Care Testing(POCT)

Sweat-based diagnostics offer an exciting avenue to noninvasively monitor analytes which had previously only been avail-able through painful blood draws.Sweat is enriched with physiologically valuable information,and recent proteomic studies have identified numerous critical analytes which have highly correlated levels in blood,interstitial fluid and sweat.How-ever,usage of sweat for health monitoring has not been studied extensively due to the substantial challenge of assembling a composite clinic-ready device.Recent advances in soft electronics have made this goal realizable,as these devices can perform electronic or optical monitoring on a flexible substrate using small volumes of liquid.While this field is still in its infancy,this review examines the physiological composition of sweat,various improvements in material science that improve sensor design,existing FDA approvals,methods of extracting sweat and comparisons to blood-based tests.Furthermore,this review assesses the critical challenges which must be overcome for this type of technology to make it out of research laboratories and into continuous clinical use.We believe that once properly harnessed,sweat-based diagnostics can provide patients a painless monitoring tool which can be customized to track a wide variety of medical conditions from the comfort of a patient’s own home.

Integrated microfluidic devices for in vitro diagnostics at point of care

Given the continuous and growing demand for point of care(POC)diagnostic tests,attention has been shifted toward integration and miniaturization of laboratory protocols into“sample-in-answer-out”devices.Microfluidic technologies have been considered an ideal solution to address the requirements of POC diagnostics since many laboratory functions can be miniaturized and incorporated onto a single integrated chip.In this review,we summarize the advances of integrated microfluidic devices for POC diagnostics in the last 3 years.Particularly,we summarize current materials used for microfluidic chip fabrication,discuss the innovation of versatile integrated microfluidic devices,especially the strategies for simplifying sample preparation in manual or self-driven systems,and new detection methods of microfluidic chips.In addition,we describe new integrated microfluidic devices for POC diagnostics of protein-targeted immunodiagnostics,nucleic acid molecular tests,and small molecule metabolites analysis.We also provide future perspectives and current challenges for clinical translation and commercialization of these microfluidic technologies.

An integrative review on the applications of 3D printing in the field of in vitro diagnostics

Biomedicine is one of the fastest growing areas of additive manufacturing.Especially,in the field of in vitro diagnostics(IVD),contributions of 3D printing include i)rapid prototyping and iterative IVD proof-of-concept designing ranging from materials,devices to system integration;ii)conceptual design simpli-fication and improved practicality of IVD products;iii)shifting the IVD applications from centralized labs to point-of-care testing(POCT).In this review,the latest developments of 3D printing and its advantages in IVD applications are summarized.A series of 3D-printed objects for IVD applications,including single-function modules,multi-function devices which integrate several single-function modules for specific an-alytical applications such as sample pre-treatment and chemo-/bio-sensing,and all-in-one systems which integrate multi-function devices and the instrument operating them,are analyzed from the perspective of functional integration.The current and potential commercial applications of 3D-printed objects in the IVD field are highlighted.The features of 3D printing,especially rapid prototyping and low start-up,en-able the easy fabrication of bespoke modules,devices and systems for a range of analytical applications,and broadens the commercial IVD prospects.