Study of the Aggregation of DNA‐Capped Gold Nanoparticles: A Smart and Flexible Aptasensor for Spermine Sensing

Abstract

As mart gold nanoparticle based aptasensor is developed for the sensing of this biomarker in ac onvenient and fast manner. Acomprehensive study was performed to elucidate the driving force of DNA adsorption,d ifferent factors' effects, such as gold nanoparticle size, DNA length, concentration, and working pH towardss permine sensing by using UV/Vis absorption spectroscopya nd isothermalt itration calorimetry.I tw as found that the developed aptasensor could detectspermine by two differ-ent sensing mechanismss imply by adjustingt he DNA concentration without complicated procedures. Good performance in complicated matrices was provenb yt he satisfactory results obtained in the spike analysis of both artificial urine and clinical urine samples. Such af lexible and smart approach described here would provide au seful tool for the fast sensing of spermine and prostatec ancer screening.[a] T.

A Highly Selective Turn-On Biosensor for Measuring Spermine/Spermidine in Human Urine and Blood

“…Thus, in this study, all biosensing works were performed in HEPES buffer at 7.4 pH. Herein, it is worthwhile to cite a few systems that are useful at acidic pHs such as pH 6, 5.5, or even 3.29. , Control experiments with AG (pure agarose hydrogel) were also performed, and the results shown in Figure S7 reveal no affinity of AG for spermine/spermidine.…”

“…Results from Figure b indicates short (≤7 s) reaction time, which is effective for practical use. It is clearly evident from Table that the detection of spermine/spermidine often challenged by other biogenic amines, ,,,, polyamines, ,,, or BSA/histamine, etc. Furthermore, biogenic amines such as putrescine and cadaverine prevail in urine.…”

“…For instrument-free detection of spermine by the hydrogel, the LOD that was visible to the naked eye appeared to be 40 μM (Figure c). Notably, nanoparticle-derived probes offer great LOD, in the order of nanomolar (nM). ,,,,− However, their saturation limits also hit at a low spermine concentration (up to several μM). Therefore, these systems are not very useful at a higher spermine concentration.…”

“…The subject, however, got increased momentum after the seminal report from Hamachi et al in which the authors have described the use of a hybrid hydrogel as an excellent fluorosensor for spermine/spermidine in artificial urine. In this work, we have compiled the literature on this topic in Table , − which shows that during the past few years, a number of nanoparticle-based probes have emerged as effective probes for the purpose of detection. The stimulating contribution from Kim et al deserves special reference in this context .…”

“…The stimulating contribution from Kim et al deserves special reference in this context . Later, a few self-assembled systems encompassing different polymer/dye/surfactant/macrocycles/quantum dots have also appeared in the literature for sensing spermine/spermidine in different real-world samples. ,,,− , Unfortunately, most of the reported systems suffer from various limitations such as tedious and complex synthetic and purification steps; ,,,,,,− inferior turn-off phenomenon; ,,,,, interference from other polyamines (e.g., putrescine, histamine, cadaverine, adamantanamine, etc. )/glutathione/NaCl; ,,,,,,,,, use of expensive gold nanoparticles; ,,,,− requirement of certain stringent conditions for stability; ,,,,,,,− inability to function at physiological pH condition; ,,− and use of organic solvent in the detection process. ,,,, …”