Journal: Biosensors

Article Title: Retention-Based, Dissociation-Sensitive Pre-Screening of Aptamers Using a Centrifugal Microspin Filter

doi: 10.3390/bios16090510

Figure Lengend Snippet: Relationship between ln-transformed W0-NRT and the literature-reported dissociation rate constants of streptavidin aptamers. W0-NRT after 10 wash cycles was calculated for 6 streptavidin aptamers, ln-transformed, and plotted against the dissociation rate constants ( k off ) reported in the literature. Each point represents one aptamer. W0-NRT values are shown as the ln-transformed mean retention obtained from three parallel process replicates, and the SD shown is that of the replicate W0-NRT values propagated through the logarithmic transformation. Each fraction was quantified by qPCR in technical triplicate. The red solid line represents the linear regression, and the gray dashed lines represent the 95% confidence band of the fitted regression line. Spearman and Pearson correlation coefficients, the corresponding p values, R 2 , and the number of aptamers analyzed are indicated in the graph. The statistical significance of the Spearman correlation was assessed using an exact two-sided test based on exhaustive enumeration of all permutations.

Article Snippet: Hydrophilic streptavidin magnetic beads (S1421S) and the Monarch Spin PCR & DNA Cleanup Kit (5 μg; T1130) were purchased from New England Biolabs (Ipswich, MA, USA).

Techniques: Transformation Assay, Dissociation Rate Constant

Journal: Biosensors

Article Title: Retention-Based, Dissociation-Sensitive Pre-Screening of Aptamers Using a Centrifugal Microspin Filter

doi: 10.3390/bios16090510

Figure Lengend Snippet: Sandwich detection of thrombin using aptamers ranked by the MSF– k off assay. ( A ) Schematic of the sandwich assay configuration. Biotinylated HD1 was immobilized on streptavidin magnetic beads as the capture aptamer, and HD22 or M03 was used as the detection aptamer for thrombin. ( B ) Amount of detection aptamer recovered after ten washes at thrombin concentrations of 0, 0.5, 5, and 50 nM, as quantified by qPCR. ( C ) Post-wash retention of HD22 and M03, calculated as W10/W0 × 100 using the corresponding unwashed value at each thrombin concentration. Data are presented as the mean ± SD of three parallel assay replicates ( n = 3), with each sample quantified by qPCR in technical triplicate. At 0 nM thrombin, the qPCR signals were below the lower limit of quantification for both detection aptamers and are indicated as NQ (

Article Snippet: Hydrophilic streptavidin magnetic beads (S1421S) and the Monarch Spin PCR & DNA Cleanup Kit (5 μg; T1130) were purchased from New England Biolabs (Ipswich, MA, USA).

Techniques: Sandwich Format Assay, Magnetic Beads, Concentration Assay