Fluorescent Nanoprobes with Oriented Modified Antibodies to Improve Lateral Flow Immunoassay of Cardiac Troponin I

Performance of nanoprobes can often determine the detection level of Lateral immunochromatography. Traditional probes were limited by the quantity and orientation of antibodies, immune activity of the Fab region or binding strength between protein and substrate. This study developed a new efficient and robust technology to construct fluorescent nanoprobes with oriented modified antibodies, based on specific binding of the Fc region of antibody with streptococcal protein G (SPG) on the surface of polystyrene microspheres (MS) and subsequent covalent cross-linking at binding sites to firm them. Lateral flow immunoassay using these probes was applied for the detection of cardiac troponin I (cTnI). The significantly improved detection sensitivity demonstrated that antibody orientation on MS surfaces effectively enhanced immunological activities of probes compared with random immobilizing methods. Furthermore, performance evaluation results of lateral flow test strips met clinical requirements perfectly, including limit of detection (0.032 ng/mL), linearity (<i>R</i> > 0.99), repeatability (CV < 10%), correlation (<i>R</i> > 0.99), and heat aging stability. This research also employed heterophilic blocking reagent (HBR) to actively block redundant binding sites of SPG for the first time in order to eliminate false positive interferences, improving the sensitivity and precision of test results further

DataSheet1_Engineered procyanidin-Fe nanoparticle alleviates intestinal inflammation through scavenging ROS and altering gut microbiome in colitis mice.PDF

Inflammatory bowel disease (IBD) is an idiopathic chronic inflammatory bowel disease characterized by inflammation, intestinal barrier injury, and imbalance of gut microbiota. Excess accumulation of reactive oxygen species (ROS) is closely correlated with the development and reoccurrence of IBD. Previous researches demonstrate that procyanidin, as a natural antioxidant, exhibits strong ability of eliminating ROS, thus showing good therapeutic effects in the inflammation-related diseases. Non-etheless, its poor stability and solubility always limits the therapeutic outcomes. Here, we typically designed an antioxidant coordination polymer nanoparticle using the engineering of procyanidin (Pc) and free iron (Fe), named Pc-Fe nanozyme, for effectively scavenging ROS and further inhibiting inflammation while altering the gut microbiome for the treatment of colitis. Furthermore, in vitro experiments uncover that Pc-Fe nanoparticles exert strong multi biomimic activities, including peroxidase, and glutathione peroxidase, for the scavenging of ROS and protecting cells from oxidative injury. In addition, the colon accumulation of Pc-Fe nanozyme effectively protects the intestinal mucosa from oxidative damage while significantly downregulates pro-inflammatory factors, repairs the intestinal barriers and alternates gut microbiome after orally administrated in sodium dextran sulfate (DSS) induced colitis mice. The results collectively illustrate that the multienzyme mimicking Pc-Fe nanozyme owns high potential for treating IBD through scavenging ROS, inhibiting inflammation, repairing gut barriers and alternating gut microbiome, which further promising its clinical translation on IBD treatment and other ROS induced intestinal diseases.</p

Distribution of the reported AHC cases in Jiangsu Province during the outbreak of September 2010.

<p>Distribution of the reported AHC cases in Jiangsu Province during the outbreak of September 2010.</p

Homology of the complete VP1 regions of the strains in different clusters within CA24v genotype GIV in this study.

<p>Homology of the complete VP1 regions of the strains in different clusters within CA24v genotype GIV in this study.</p

AHC cases reported to NDSIMS in Jiangsu from 2007 to 2010.

<p>AHC cases reported to NDSIMS in Jiangsu from 2007 to 2010.</p

Amino acid mutations in the 3Cpro region in different genotypes of CA24v.

*<p>Amino acid mutation only present in all GIV-C5 strains.</p

Phylogenetic analysis based on the 915-nucleotide VP1 gene of CA24v.

<p>All Jiangsu CA24v isolates identified in this study, marked with black triangles, were compared with strains available in GenBank. Strains for which the complete sequences of both the 3Cpro and VP1 regions were available are indicated **. The MEGA 4.0 software was used for the phylogenetic analysis. The stability of the nodes was assessed using neighbor-joining cluster analysis with 1000 bootstrap replications, and only bootstrap values >70% are shown at the nodes.</p

Homology of the complete 3Cpro regions of the strains in different clusters within CA24v genotype GIV investigated in this study.

<p>Homology of the complete 3Cpro regions of the strains in different clusters within CA24v genotype GIV investigated in this study.</p

Amino acid mutations in the VP1 region in different genotypes of CA24v.

*<p>Amino acid mutation only present in all GIV-C5 strains.</p

Phylogenetic analysis based on the 549-nucleotide 3Cpro gene of CA24v.

<p>All Jiangsu CA24v isolates identified in this study, marked with black triangles, were compared with strains available in GenBank. Strains for which the complete sequences of both the 3Cpro and VP1 regions were available are indicated with **. The MEGA 4.0 software was used for the phylogenetic analysis. The stability of the nodes was assessed using neighbor-joining cluster analysis with 1000 bootstrap replications, and only bootstrap values >70% are shown at the nodes.</p