Polymeric delivery systems have been extensively studied to achieve localized and controlled release of protein drugs. However, it is still challenging to control the release of multiple protein drugs in distinct stages according to the progress of disease or treatment. This study successfully demonstrates that multiple protein drugs can be released from aptamer-functionalized hydrogels with ad...

We report on a novel strategy for DNA aptamer immobilization to develop sensitive electrochemical detection of a protein biomarker, with prostate specific antigen (PSA) as a case biomarker. Thiolated single-stranded DNA (ssDNA) was co-immobilized with 3-mercapto-1-propanol on gold electrodes, and used as a scaffold for DNA aptamer attachment through hybridization of the aptamer overhang (so-cal...

Although several imaging modalities are widely used for tumor imaging, none are tumor type-specific. Different types of cancer exhibit differential therapeutic responses, thus necessitating development of an imaging modality able to detect various tumor types with high specificity. To illustrate this point, CD30-specific oligonucleotide aptamer in vivo imaging probes were conjugated to the near...

A label-free aptasensor for platelet-derived growth factor (PDGF) protein is reported. The aptasensor uses mixed self-assembled monolayers (SAMs) composed of a thiol-modified PDGF binding aptamer and 6-mercaptohexanol (MCH) on a gold electrode. The SAMs were characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV) before an...

A fiber-optic biosensor using an aptamer receptor has been developed for the measurement of thrombin. An antithrombin DNA aptamer was immobilized on the surface of silica microspheres, and these aptamer beads were distributed in microwells on the distal tip of an imaging fiber. A different oligonucleotide bead type prepared using the same method as the aptamer beads was also included in the mic...

High-mobility group A2 (HMGA2) protein regulates retinoblastoma (RB) cancer cell proliferation. Here, a stable phosphorothioate-modified HMGA2 aptamer was used to block HMGA2 protein function in RB cells. HMGA2-aptamer internalisation in RB cells (Y79, Weri Rb1) and non-neoplastic human retinal cells (MIO-M1) were optimised. Aptamer induced dose-dependent cytotoxicity in RB cancer cells (0.25-1...

We identified an RNA aptamer that induces TetR-controlled gene expression in Escherichia coli when expressed in the cell. The aptamer was found by a combined approach of in vitro selection for TetR binding and in vivo screening for TetR induction. The smallest active aptamer folds into a stem-loop with an internal loop interrupting the stem. Mutational analysis in vivo and in-line probing in vi...

Riboswitches, whose folding is controlled by binding of metabolites to the aptamer domain, regulate downstream gene expression. Folding properties of the aptamer strongly influence the conformation of the downstream expression platform, which controls transcription termination or translation initiation. We have characterized the energy landscape of the add riboswitch aptamer quantitatively by u...

Aptamers have emerged as a new class of small molecule ligands. These short, single-stranded oligonucleotides can be produced through simple chemical synthesis, making them easier and less costly to produce than antibodies. We synthesized an RNA aptamer probe specific for human CD4 using a reported sequence and investigated the potential use of this probe in cell phenotyping. Studies in culture...

Abstract Background Procalcitonin (PCT) is a protein that can be used as biomarker for sepsis detection. Sepsis disease where early diagnosis crucial. Using PCT new alternative overcomes limitations of traditional diagnostic methods. Objective To develop platform detection using novel material called aptamer. Results Aptamers could specifically bind to were selected and various molecular biolog...