Search results for "aptamer"

Prophylaxis of Pseudophakic Cystoid Macular Edema with Intraoperative Pegaptanib

2011

The purpose of this study was to determine the efficacy of an intraoperative intravitreal pegaptanib injection during phacoemulsification in preventing the development of pseudophakic cystoid macular edema (CME) following cataract surgery.This prospective, controlled pilot study was carried out at the Department of Ophthalmology, Nuevo Hospital Universitario y Politécnico La Fe, Valencia (Spain). Five hundred patients with cataract and healthy retina were included in the study. Patients were assigned in a 1:1 ratio to receive an intraoperative intravitreal pegaptanib injection (n=250) or not (control group, n=250) associated with standardized phacoemulsification surgery and postoperative tr…

Implantable Sensors Based on Gold Nanoparticles for Continuous Long-Term Concentration Monitoring in the Body.

2021

Implantable sensors continuously transmit information on vital values or biomarker concentrations in bodily fluids, enabling physicians to survey disease progression and monitor therapeutic success. However, currently available technologies still face difficulties with long-term operation and transferability to different analytes. We show the potential of a generalizable platform based on gold nanoparticles embedded in a hydrogel for long-term implanted biosensing. Using optical imaging and an intelligent sensor/reference-design, we assess the tissue concentration of kanamycin in anesthetized rats by interrogating our implanted sensor noninvasively through the skin. Combining a tissue-integ…

Aptamer-embedded DNA origami cage for detecting (glycated) hemoglobin with a surface plasmon resonance sensor

2020

DNA origami-based cages functionalized with aptamer motifs, were used to detect hemoglobin and glycated hemoglobin. The binding between the cages and hemoglobin was monitored using a surface plasmon resonance (SPR) sensor. One DNA strand in the nano-cage was replaced with an aptamer that demonstrated a high affinity to hemoglobin (Hb) or glycated hemoglobin (gHb). Three types of the DNA nano-cages designed to fit the size and shape of hemoglobin were evaluated: one without an aptamer, one with the Hb-affinity aptamer (HA) and one with the gHb-affinity aptamer (GHA). Both DNA nano-cages embedded with HA and GHA showed significantly more stable binding with Hb and gHb by 5 and 9 times, respec…

Smart Sorption Materials in Green Analytical Chemistry

2019

The use of smart materials as alternative sorption materials for their use in greening sample preparation has been reviewed. It has been taking into consideration recent advances on the use of natural products, without any modification or purification, for making analyte extraction and pre-concentration and the use of specific materials in solid-phase extraction (SPE) and solid-phase microextraction (SPME) approaches. Inorganic materials, such as metal oxides, alumina-based, silica-based, and carbon-based materials together with biomimetic sorbents such as classical immunosorbents, aptamers, and molecularly imprinted polymers, have been reviewed as examples of these materials, stressing the…

Nano-materials for use in sensing of salmonella infections: Recent advances

2016

Salmonella infectious diseases spreading every day through food have become a life-threatening problem for millions of people and growing menace to society. Health expert's estimate that the yearly cost of all the food borne diseases is approximately $5-6 billion. Traditional methodologies for salmonella analysis provide high reliability and very low limits of detection. Among them immunoassays and Nucleic acid-based assays provide results within 24h, but they are expensive, tedious and time consuming. So, there is an urgent need for development of rapid, robust and cost-effective alternative technologies for real-time monitoring of salmonella. Several biosensors have been designed and comm…

Recent advances in aptamer-based miniaturized extraction approaches in food analysis

2021

Abstract Sample preparation is a relevant step in food analysis to achieve adequate extraction and preconcentration of target analytes before their introduction in the analytical system. Current trends in sample preparation involve moving towards miniaturized extraction devices combined with advanced affinity-based sorbents. Within affinity-based materials, aptamer-based ones have attracted much attention due to their excellent molecular recognition properties, high stability, and the possibility of immobilization onto the surface of different supporting materials, such as nanoparticles, monolithic stationary phases, etc. This review gives an overview of the literature published regarding a…

Smart Materials for Solid-Phase Extraction Applications

2019

Ensuring food safety using aptamer based assays: Electroanalytical approach

2020

Aptamers, are being increasingly employed as favorable receptors for constructing highly sensitive biosensors, for their remarkable affinities towards certain targets including a wide scope of biological or chemical substances, and their superiority over other biologic receptors. The selectivity and affinity of the aptamers have been integrated with the wise design of the assay, applying suitable modifications, such as nanomaterials on the electrode surface, employing oligonucleotide-specific amplification strategies or, their combinations. After successful performance of the electrochemical aptasensors for biomedical applications, the food sector with its direct implication for human healt…

Nanomaterial-based cocaine aptasensors.

2015

Up to now, many different methods have been developed for detection of cocaine, but most of these methods are usually time-consuming, tedious and require special or expensive equipment. Therefore, the development of simple, sensitive and rapid detection methods is necessary. In the last decade, aptamers have been used as a new biosensor platform for detection of cocaine in different samples. Aptamers are artificial single-stranded DNA or RNA oligonucleotides capable of binding to specific molecular targets with high affinity and if integrated to nanomaterials, it may lead in precise methods for cocaine detection in the common laboratories. In this review, recent advances and applications of…

Intravitreal pegaptanib sodium for refractory pseudophakic macular oedema.

2008

Evaluate the efficacy of intravitreal pegaptanib sodium (Macugen®) in refractory pseudophakic cystoid macular oedema (CME). Prospective, nonrandomized, interventional case series. Four eyes of four patients with refractory pseudophakic CME to pars plana vitrectomy and intravitreal bevacizumab and triamcinolone, were treated with pegaptanib sodium, with a mean follow up of 4 months. Pre- and postinfection examinations included assessment of best-corrected visual acuity (BCVA) using the Early Treatment Diabetic Retinopathy Study chart (ETDRS), fluorescein angiography (FA), and optical coherence tomography (OCT). Visual acuity increased in all patients after intravitreal pegaptanib sodium. OCT…