Development and validation of dot-ELISA on modified cellulose filter paper: a simplified novel approach

Abstract

GMA-g-CFP matrix validated for dot-ELISA exhibits specificity and sensitivity comparable to the commercial NC membrane and is relevant for mass screening in field conditions as in epidemiological studies.

Cellulose grafting by photoinduced controlled radical polymerisation

“…For the S-S BiB grafted filter papers, the 35 M n reported for the DP 600 polymers were closer to the theoretical M n , possibly suggesting a higher efficiency of the sacrificial initiator in these reactions. The dispersities for the polymers formed from the sacrificial initiator were 1.1 for all reactions, showing the formation of well-defined polymers.. 40 The chains grafted from the S-S BiB modified filter papers were cleaved by the utilisation of DTT, as previously reported. 38 FT-IR spectra ( Figure S1) of the filter papers before and after cleavage revealed that the intensity of the carbonyl peak was strongly reduced after cleavage indicating that a majority of the 45 polymer had been cleaved of the surface.…”

“…The carbonyl 35 peak intensity in the spectrum revealed that all the papers had been grafted with relatively large amounts of polymer. The agreement in the intensity of the peaks from duplicate samples demonstrated that there was more polymer grafted on the filter papers grafted in the reactions with target DP 600, showing that it 40 was possible to regulate the amount of grafted polymer by altering the target DP using a sacrificial initiator. The intensity of the carbonyl peak in the spectrum was significantly higher than the typical intensities reported for polymer grafted filter paper, 28,29,[40][41][42] showing the efficiency of the photoinduced CRP method.…”

“…This ensured that the free polymer formed from the sacrificial initiator in bulk was removed by the selected washing procedure, and that no 35 polymerisation was initiated from filter paper if no immobilised initiator was present. Second, a BiB modified filter paper was placed in DMSO and monomer and subjected to the same conditions in terms of temperature, time and UV light exposure, as the grafted filter paper to ensure that no polymerisation occurs 40 without the catalyst complex present.…”

“…Conversions, molecular weights and dispersities of the free polymers were determined from 1 H NMR and SEC (Table 2, figure S6-S8). The target DP 40 for all three monomer compositions for the copolymerisation of αClεCL and ɛCL was 100. The final molecular weights of the polymer formed from the sacrificial initiator were significantly lower for all three polymerisations than the theoretical molecular weight calculated from 1 H NMR.…”

“…15 They observed that the rate of polymerisation was increased by light compared to when the reaction was performed in the dark. They also discovered that 40 there was an increase in the control of the polymerisation when it was exposed to light during the reaction. More recently, several studies using ultra-violet (UV) and visible light have been demonstrated to trigger metal complex mediated radical polymerisations.…”