streptavidin coated aunps  (Bangs Laboratories)

Journal: bioRxiv

Article Title: Nanoparticle-Supported, Rapid, Digital Quantification of Neutralizing Antibodies Against SARS-CoV-2 Variants

doi: 10.1101/2024.11.05.622148

Figure Lengend Snippet: (a) NasRED-tAb (total antibody) sensing preparation: RBD (or S1)-AuNPs formation by streptavidin-biotin reaction, and then simple mixing with Ab-containing sample. (b) NasRED-nAb (neutralizing antibody) sensing preparation: ACE2-AuNPs formation by streptavidin-biotin reaction and mixing of ACE2-AuNPs, nAb-containing sample, and streptavidin-formed multivalent S1 (or RBD) molecules. The multivalent-S1 (or RBD) molecules are created by mixing biotinylated RBD or S1 with streptavidin and used to evaluate the competition of ACE2-AuNPs and nAbs for binding. (c-e) Rapid detection process comprising centrifugation of the mixtures to create a high-concentration region for accelerated reaction, followed by 20 minutes of incubation time allowing the stable clusters formation, and subsequently resuspension of the non-reacting AuNPs by vortex agitation. (f,g) Key components of the portable electronic readout system comprise an LED, a photodetector, a tube chamber, and (g) signal digitalization customized circuitry. (h-i) Representative data highlight the differences between NaSRED-tAb and NasRED-nAb assays: (left) schematics of Ab-modulated AuNP cluster distributions, where Abs trigger the formation of AuNP clusters for tAb assay but nAbs block streptavidin-RBD proteins from binding to ACE2-AuNPs; (right) sensing curves plotting normalized optical signals (transmission T PED for tAb and extinction E PED for nAb) against AS35 (red) and CR3022 (black) using WT-RBD-functionalized AuNP sensors for tAb and ACE2 functionalized AuNP sensors and multivalent WT-RBD for nAb. NC stands for negative control. T PED and E PED were obtained by averaging signals collected along five different orientations in the PED tube holder for each sample (Methods section).

Article Snippet: Streptavidin-coated AuNPs (∼0.13 nM, 80 nm, optical density (OD)10) were purchased from Cytodiagnostics.

Techniques: Binding Assay, Centrifugation, Concentration Assay, Incubation, Blocking Assay, Transmission Assay, Negative Control

Journal: bioRxiv

Article Title: Nanoparticle-Supported, Rapid, Digital Quantification of Neutralizing Antibodies Against SARS-CoV-2 Variants

doi: 10.1101/2024.11.05.622148

Figure Lengend Snippet: (a) Images of tubes displaying color changes in AuNP solutions of different concentrations corresponding to the optical density (OD) values provided by the manufacturer (Cytodiagnostics). The AuNPs obtained from Cytodiagnostics were reported to have an initial optical density OD of 10. In this context, OD is the base-10 logarithm of the ratio between incident and transmitted optical power. A higher OD indicates greater extinction and a higher concentration of AuNPs. (b) The electronic readout signal OD PED plotted as a function of the manufacturer-provided OD values, with a linear fit described by the equation OD PED = 0.3 × OD + 0.06.

Article Snippet: Streptavidin-coated AuNPs (∼0.13 nM, 80 nm, optical density (OD)10) were purchased from Cytodiagnostics.

Techniques: Concentration Assay

Journal: BMC Microbiology

Article Title: Rapid, visual, label-based biosensor platform for identification of hepatitis C virus in clinical applications

doi: 10.1186/s12866-024-03220-9

Figure Lengend Snippet: Schematic diagram of HCV-RT-LAMP-AuNPs-LFB assay’s principle. ( A ) Schematic diagram of AuNPs-LFB principles for the interpretation of HCV-RT-LAMP outcomes. I, HCV-RT-LAMP amplification products (2.0 µl) and running buffer (100 µl) are added simultaneously on the sample pad. II, Due to capillary action, the running buffer containing HCV-RT-LAMP products move forward onto the conjugate pad and nitrocellulose (NC) membrane. The dye streptavidin-coated gold nanoparticles (streptavidin-AuNPs) are rehydrated and integrate with FAM/biotin labeled HCV-RT-LAMP products. III, The FAM/biotin-labeled HCV-RT-LAMP products are captured by anti-FAM at the test line (TL). Streptavidin-AuNPs are captured by biotin-BSA at the control line (CL). IV, Interpretation of the HCV-RT-LAMP-AuNPs-LFB assay. HCV-positive results are indicated by CL and TL bands on the AuNPs-LFB. Negative results are indicated when only the CL band appears on the AuNPs-LFB. ( B ) Workflow of the HCV-RT-LAMP-AuNPs-LFB assay. The workflow comprises the following closely linked steps: rapid genomic RNA extraction (step 1), RT-LAMP amplification (step 2), and AuNPs-LFB visual interpretation (step 3). The entire detection process is complete within 40 min

Article Snippet: Crimson dye streptavidin-coated AuNPs (40 ± 5 nm, 10 mg/ml) were obtained from Bangs Laboratories Inc. (Fishers, IN, USA).

Techniques: Amplification, Membrane, Labeling, Control, RNA Extraction

Journal: BMC Microbiology

Article Title: Rapid, visual, label-based biosensor platform for identification of hepatitis C virus in clinical applications

doi: 10.1186/s12866-024-03220-9

Figure Lengend Snippet: The HCV-RT-LAMP-AuNPs-LFB primers used in this study

Article Snippet: Crimson dye streptavidin-coated AuNPs (40 ± 5 nm, 10 mg/ml) were obtained from Bangs Laboratories Inc. (Fishers, IN, USA).

Techniques: Sequencing

Journal: BMC Microbiology

Article Title: Rapid, visual, label-based biosensor platform for identification of hepatitis C virus in clinical applications

doi: 10.1186/s12866-024-03220-9

Figure Lengend Snippet: Pathogens used in this study

Article Snippet: Crimson dye streptavidin-coated AuNPs (40 ± 5 nm, 10 mg/ml) were obtained from Bangs Laboratories Inc. (Fishers, IN, USA).

Techniques: Construct, Plasmid Preparation, Virus

Journal: BMC Microbiology

Article Title: Rapid, visual, label-based biosensor platform for identification of hepatitis C virus in clinical applications

doi: 10.1186/s12866-024-03220-9

Figure Lengend Snippet: Verification of HCV-RT-LAMP products. The HCV-RT-LAMP products were identified simultaneously using ( A ) 2% agarose gel electrophoresis, ( B ) color change (L-HNB), and ( C ) AuNPs-LFB. Templates of 1–8 were HCV-1b plasmid, HCV-2a plasmid, HCV 3b plasmid, HCV-6a plasmid, HCV-3a plasmid, hepatitis B virus (HBV), human immunodeficiency virus (HIV), and distilled water (DW), respectively. CL: control line; TL: test line

Article Snippet: Crimson dye streptavidin-coated AuNPs (40 ± 5 nm, 10 mg/ml) were obtained from Bangs Laboratories Inc. (Fishers, IN, USA).

Techniques: Agarose Gel Electrophoresis, Plasmid Preparation, Virus, Control

Journal: BMC Microbiology

Article Title: Rapid, visual, label-based biosensor platform for identification of hepatitis C virus in clinical applications

doi: 10.1186/s12866-024-03220-9

Figure Lengend Snippet: Sensitivity analysis of the HCV-RT-LAMP-AuNPs-LFB assay with serial dilutions of nucleic acid template. Visual reagent (L-HNB) and AuNPs-LFB approaches were simultaneously used to readout the HCV-RT-LAMP outcomes. L-HNB ( A )/AuNPs-LFB ( B ); 1–6 represent the HCV plasmid concentrations of 2.0 × 10 3 copies, 2.0 × 10 2 copies, 2.0 × 10 1 copies, 2.0 × 10 0 copies, and 1 copy per test and distilled water (DW), respectively. The limit of detection (LoD) of the HCV-RT-LAMP assay was 20 copies per test. CL: control line; TL: test line

Article Snippet: Crimson dye streptavidin-coated AuNPs (40 ± 5 nm, 10 mg/ml) were obtained from Bangs Laboratories Inc. (Fishers, IN, USA).

Techniques: Plasmid Preparation, RT Lamp Assay, Control

Journal: BMC Microbiology

Article Title: Rapid, visual, label-based biosensor platform for identification of hepatitis C virus in clinical applications

doi: 10.1186/s12866-024-03220-9

Figure Lengend Snippet: Amplification time optimization for the HCV-RT-LAMP-AuNPs-LFB assay. Four RT-LAMP reaction times, including 10 min ( A ), 20 min ( B ), 30 min ( C ), and 40 min ( D ), were evaluated at optimal reaction conditions. Tube/biosensor 1–6 represent HCV plasmid concentrations of 2.0 × 10 3 copies, 2.0 × 10 2 copies, 2.0 × 10 1 copies, 2.0 × 10 0 copies, and 1 copy per test and distilled water (DW), respectively. The results were analyzed simultaneously using visual reagent L-HNB and AuNPs-LFB. The signal of the LoD appeared with a 30 min reaction time through AuNPs-LFB. CL, control line; TL, test line

Article Snippet: Crimson dye streptavidin-coated AuNPs (40 ± 5 nm, 10 mg/ml) were obtained from Bangs Laboratories Inc. (Fishers, IN, USA).

Techniques: Amplification, Plasmid Preparation, Control

Journal: BMC Microbiology

Article Title: Rapid, visual, label-based biosensor platform for identification of hepatitis C virus in clinical applications

doi: 10.1186/s12866-024-03220-9

Figure Lengend Snippet: HCV-RT-LAMP-AuNPs-LFB assay specificity with different strains. Assay specificity was evaluated using different nucleic acid templates. Each result was tested through AuNPs-LFB: 1–5, HCV 1b, 2a, 3b, 6a, and 3a 5’UTR plasmids; 6–11, HCV clinical samples; 12, Hepatitis B virus; 13, Human immunodeficiency virus; 14, Epstein-Barr virus; 15, Coxsackie virus CAV16; 16, Human papillomavirus; 17, Human enterovirus EV71; 18, Influenza A virus; 19, Influenza B virus; 20, Cryptococcus neoformans ; 21, Enterococcus faecium ; 22, Salmonella enteritidis ; 23, Shigella bogdii ; 24, Staphylococcus aureus ; 25, Streptococcus pyogenes ; 26, Streptococcus pneumoniae ; 27, Escherichia coli ; 28, Pseudomonas aeruginosa ; 29, Klebsiella pneumoniae ; 30, Mycobacterium tuberculosis ; 31, Brucella ; 32, Other microbial nucleic acid mixtures containing HCV-1b plasmids; 33, Other microbial nucleic acid mixtures containing HCV-2a plasmids; 34, Other microbial nucleic acid mixtures containing HCV-3b plasmids; 35, Other microbial nucleic acid mixtures containing HCV-6a plasmids; 36, Other microbial nucleic acid mixtures containing HCV-3a plasmids; 37, Other microbial nucleic acid mixtures; 38, distilled water (DW). CL, control line; TL, test line

Article Snippet: Crimson dye streptavidin-coated AuNPs (40 ± 5 nm, 10 mg/ml) were obtained from Bangs Laboratories Inc. (Fishers, IN, USA).

Techniques: Virus, Control

Journal: BMC Microbiology

Article Title: Rapid, visual, label-based biosensor platform for identification of hepatitis C virus in clinical applications

doi: 10.1186/s12866-024-03220-9

Figure Lengend Snippet: Comparing HCV levels in clinical samples using RT-qPCR and our HCV-RT-LAMP-AuNPs-LFB methods

Article Snippet: Crimson dye streptavidin-coated AuNPs (40 ± 5 nm, 10 mg/ml) were obtained from Bangs Laboratories Inc. (Fishers, IN, USA).

Techniques:

Journal: BMC Microbiology

Article Title: Rapid, visual, label-based biosensor platform for identification of hepatitis C virus in clinical applications

doi: 10.1186/s12866-024-03220-9

Figure Lengend Snippet: Comparison of the commonly used methods for HCV detection

Article Snippet: Crimson dye streptavidin-coated AuNPs (40 ± 5 nm, 10 mg/ml) were obtained from Bangs Laboratories Inc. (Fishers, IN, USA).

Techniques: Comparison, Enzyme-linked Immunosorbent Assay, Infection, Real-time Polymerase Chain Reaction, CRISPR, Biosensor Assay