Abstract Molecular switches that change their conformation upon target binding offer powerful capabilities for biotechnology and synthetic biology. Aptamers are useful as molecular because they excellent properties, undergo reversible folding, can be engineered into many nanostructures. Unfortunately, the thermodynamic kinetic properties of aptamer developed to date intrinsically coupled, such high temporal resolution only achieved at cost lower sensitivity or background. Here, we describe a...

We present a generalizable approach for designing biosensors that can continuously detect small-molecule biomarkers in real time and without sample preparation. This is achieved by converting existing antibodies into target-responsive "antibody-switches" enable continuous optical biosensing. To engineer these switches, are linked to molecular competitor through DNA scaffold, such competitive target binding induces scaffold switching fluorescent signaling of changing concentrations. As...

Aptamers are a promising class of affinity reagents because signal transduction mechanisms can be built into the reagent, so that they directly produce physically measurable output upon target binding. However, endowing functionality an aptamer remains trial-and-error process compromise its or specificity and typically requires knowledge ligand binding domain structure. In this work, design architecture convert existing "reversible switch" whose kinetic thermodynamic properties tuned without...

Abstract Aptamer switches that respond sensitively to pH could enhance control over molecular devices, improving their diagnostic and therapeutic efficacy. Previous designs have inserted pH-sensitive DNA motifs into aptamer sequences. Unfortunately, performance was limited by the motifs’ intrinsic pH-responses not be tuned operate across arbitrary ranges. Here, we present a methodology for converting virtually any switch with pH-selective binding properties — in acidic, neutral, or alkaline...

The development of receptors suitable for the continuous detection analytes in complex, interferent-rich samples remains challenging. Antibodies are highly sensitive but difficult to engineer order introduce signaling functionality, while aptamer switches easy construct often yield only a modest target sensitivity. We present here programmable antibody and DNA switch (PANDAS), which combines desirable properties both by using nucleic acid tether link an analyte-specific internal...

Abstract Almost all biosensors that use ligand-receptor binding operate under equilibrium conditions. However, at low ligand concentrations, the equilibration with receptor (e.g., antibodies and aptamers) becomes slow thus equilibrium-based are inherently limited in making measurements both rapid sensitive. In this work, we provide a theoretical foundation for method through which can quantitatively measure concentration before reaching equilibrium. Rather than only measuring single...

Abstract Current technology for measuring specific biomarkers – continuously in complex samples, without sample preparation is limited to just handful of molecules such as glucose and blood oxygen. In this work, we present the first optical biosensor system that enables continuous detection a wide range human plasma. Our employs modular duplex-bubble switch (DBS) architecture converts aptamers into structure-switching fluorescence probes whose affinity kinetics can be readily tuned. These...

Abstract For more than fifty years, the enzyme‐linked immunosorbent assay (ELISA) serves as gold standard for protein biomarker detection. However, conventional ELISA requires considerable sample preparation including reagent addition, incubation, and washing steps, limiting its usefulness at point‐of‐care. In this work, “instant ELISA” (fluorophore‐linked assay) biosensor that can measure biomarkers in picomolar range within 15 min undiluted plasma or serum with no is described. The sensor...

ConspectusContinuous biosensors have the potential to transform medicine, enabling healthcare be more preventative and personalized as compared current standard of reactive diagnostics. Realizing this transformative requires that can function continuously in vivo without sample preparation deliver molecular specificity, sensitivity, high temporal resolution. Molecular switches stand out a promising solution for creating such sensors continuous detection many different types molecules. are...

DNA switches that can change conformation in response to certain wavelengths of light could enable rapid and noninvasive control chemical processes for a wide range applications. However, most current photoresponsive are limited by either irreversible switching or reversible with impractically slow kinetics. Here, we report the design an intramolecular triplex photoswitch (TPS) based on single-stranded undergoes photoswitching between folded unfolded states through isomerization internal...

Cells rely on secreted signaling molecules to coordinate essential biological functions including development, metabolism, and immunity. Unfortunately, such processes remain difficult measure with sufficient chemical specificity temporal resolution. To address this need, an aptamer-conjugated hydrogel matrix that enables continuous fluorescent measurement of specific analytes - in two dimensions, real-time is developed. As a proof concept, imaging inter-cellular cyclic adenosine...

Abstract Cells rely on secreted signaling molecules to coordinate essential biological functions including development, metabolism, and immunity. Unfortunately, such processes remain difficult measure with sufficient chemical specificity temporal resolution. To address this need, we have developed an aptamer-conjugated hydrogel matrix that enables continuous fluorescent measurement of specific analytes – in two dimensions, real-time. As a proof concept, performed real-time imaging...

Abstract We present a generalizable approach for designing biosensors that can continuously detect specific biomarkers in real time and without sample preparation. This is achieved by converting existing antibodies into target-responsive “antibody-switches” enable continuous optical biosensing. To engineer these switches, are linked to molecular competitor through DNA scaffold, such competitive target binding induces scaffold switching fluorescent signaling of changing concentrations. As...

Abstract Molecular switches that change their conformation upon target binding offer powerful capabilities for biotechnology and synthetic biology. In particular, aptamers have proven useful as molecular because they excellent properties, undergo reversible folding, can be readily engineered into a wide range of nanostructures. Unfortunately, the thermodynamic kinetic properties aptamer developed to date are intrinsically coupled, such high temporal resolution ( i.e. , switching time) only...

Abstract Since its invention in the 1970’s, enzyme-linked immunosorbent assay (ELISA) has served as “gold-standard” for blood and plasma protein biomarker quantification. However, ELISAs require significant amounts of sample preparation entailing multiple reagent additions, incubations, washing steps, limiting their clinical usefulness context diagnosis prognosis rapidly evolving medical conditions. In this work, we describe ‘instant ELISA’ biosensor platform, a probe that can be exposed...

Cellular Signaling Cells communicate through secreted biomolecules, however there are few tools to directly record these signals. In article number 2306704, Chan Ho Park, H. Tom Soh, and co-workers report that embedding fluorescent aptamer sensors within a biocompatible hydrogel enables tracking of cell-to-cell signaling with molecular specificity high temporal resolution, demonstrated by monitoring the signals driving slime mold cell migration. This technology should be applicable for...

As a regional staple that is of considerable cultural and economic significance in the Bali region, Arak subject this study, which aims to investigate influence social media marketing, brand image, word mouth have on decisions customers make about purchase Bali. In preliminary study with 10 participants, it was discovered twenty percent respondents were more interested purchasing Bali, while eighty preferred alcoholic beverages imported from other countries. This finding survey. For purpose...

Abstract The development of receptors suitable for the continuous detection analytes in complex, interferent-rich samples remains challenging. Antibodies are highly sensitive but difficult to engineer order introduce signaling functionality, while aptamer switches easy construct often yield only modest target sensitivity. We present here programmable antibody and DNA switch (PANDAS), which combines best features both systems by using a nucleic acid tether link an analyte-specific internal...

Abstract Aptamer switches that respond sensitively to local variations in pH could enable the development of molecular devices greatly enhance diagnostic accuracy and therapeutic efficacy. Previous design strategies relied on inserting a known pH-sensitive DNA motif into aptamer structure. Unfortunately, their performance was ultimately governed by intrinsic pH-response inserted not be readily tuned operate across arbitrary ranges. In this work, we present general methodology for converting...

Abstract Almost all biosensors that use ligand-receptor binding operate under equilibrium conditions. However, at low ligand concentrations, the equilibration with receptor ( e.g. , antibodies and aptamers) become slow thus equilibrium-based are inherently limited in making measurements both rapid sensitive. In this work, we provide a theoretical foundation for novel method through which can quantitatively measure concentration before reaching equilibrium. Rather than only measuring single...

Abstract DNA switches that can change conformation in response to certain wavelengths of light could enable rapid and non-invasive control chemical processes for a wide range applications. However, most current photo-responsive are limited either by irreversible switching or reversible with impractically slow kinetics. Here, we report the design an intramolecular triplex photoswitch (TPS) based on single-stranded undergoes photoswitching between folded unfolded states through isomerization...