We report a simple and highly sensitive colorimetric method for the detection and quantification of proteins, based on the aggregation of ascorbic acid (AA) capped gold nanoparticles (AuNPs) by proteins. The interactions between our AuNPs and nine different proteins of various sizes and shapes (cytochrome C (12 kDa), lysozyme (14.3 kDa), myoglobin (17 kDa), human serum albumin (66 kDa), bovine serum albumin (66.4 kDa), human transferrin (80 kDa), aldolase (160 kDa), catalase (240 kDa), and human H-ferritin (500 kDa)) generated similar AuNPs-protein absorption spectra in a concentration-dependent manner in the range of 1-15 nM. Upon the addition of a protein, the UV-visible spectra of AuNPs-protein conjugates shifted from 524 nm for the AuNps alone to longer wavelength (600-750 nm) due to the presence of one of these proteins. This bathochromic shift is accompanied by a color change from a cherry red, to dark purple, and then light grey or colorless if excess protein has been added, indicating the formation of AuNPs-protein conjugates followed by protein-induced aggregation of the AuNPs. High-resolution transmission electron microscopy images revealed uniformly distributed spherical nanoparticles with an average size of 27.5 ± 15.2 nm, increasing in size to 39.6 ± 12.9 nm upon the addition of a protein, indicating the formation of AuNPs-protein conjugates in solution. A general mechanism for the protein-induced aggregation of our AuNPs is proposed. The consistent behavior observed with the nine proteins tested in our study suggests that our assay can be universally applied for the quantification of pure proteins in a solution, regardless of size, shape, or molecular weight.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1039/d4ay01146e | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
To inhibit endocytic entry of some viruses, cells promote acidification of endosomes by expressing the short isoform of human nuclear receptor 7 (NCOA7) which increases activity of vacuolar ATPase (V-ATPase). While we found that HIV-1 infection of primary T cells led to acidification of endosomes, NCOA7 levels were only marginally affected. Contrastingly, levels of the 50 kDa form of the sodium/hydrogen exchanger 6 (NHE6) were greatly reduced.
View Article and Find Full Text PDFMammalian red blood cells are generated via a terminal erythroid differentiation pathway culminating in cell polarization and enucleation. Actin filament polymerization is critical for enucleation, but the molecular regulatory mechanisms remain poorly understood. We utilized publicly available RNA-seq and proteomics datasets to mine for actin-binding proteins and actin- nucleation factors differentially expressed during human erythroid differentiation and discovered that a focal adhesion protein-Tensin-1-dramatically increases in expression late in differentiation.
View Article and Find Full Text PDFUnravelling a new focus of Spotted Fever Rickettsioses as causative agents of acute undifferentiated febrile illness in Odisha, A state in eastern Costal India.
Acta Trop
January 2025
Professor, Department of Paediatrics, All India Institute of Medical Sciences [AIIMS], Bhubaneswar, Odisha.751019. Electronic address:
Spotted fever group Rickettsia (SFGR) infections remain largely under-investigated as causative agents of acute undifferentiated febrile illness (AUFI) in resource-limited settings. Few studies are available on the prevalence of SFGR infections in India, especially in eastern India. In a cross-sectional study conducted in 192 hospitalized adult and paediatric patients with AUFI, the frequency of SFGR using sequential PCR targeting genes encoding citrate synthase gene (gltA), 17 kDa lipoprotein precursor antigen (17kDa), outer membrane proteins A and B (omp A & omp B) was 6.
View Article and Find Full Text PDFStudy of Different Cultivated Plants Rhizosphere Soil Fungi-Mediated Pectinase: Insights into Production, Optimization, Purification, Biocompatibility, and Application.
Microb Ecol
January 2025
Department of Botany, Faculty of Science, Fayoum University, Fayoum, 63511, Egypt.
Microorganisms are preferred as an enzyme source due to their short lifespan, high production rate, affordability, and absence of harmful chemicals in enzymes generated from plant and animal sources. Fungi communities are biological factories for many bioactive compounds such as the important industrial enzyme pectinase. The current study dealt with production, optimization, purification, biocompatibility, and application of fungal pectinase obtained from five plant rhizospheres (banana, jarawa, lemon, tomato, and wheat) at Fayoum Governorate, Egypt.
View Article and Find Full Text PDFA Nanotheranostic Agent for Synergistic Antitumor Chemo/Phototherapy Prepared by Paclitaxel-Induced Self-Assembly of PEGylated Human Serum Albumin with Prolonged Circulation.
ACS Omega
December 2024
Key Laboratory of Chemical Biology of Natural Products (Ministry of Education), Institute of Biochemical and Biotechnological Drugs, School of Pharmaceutical Sciences, Shandong University, Jinan, Shandong 250012, China.
The integration of different therapies to enhance the efficacy and minimize adverse reactions has become popular recently. This approach leverages the complementary mechanisms of action of different treatments, which can lead to better therapeutic outcomes and reduced side effects. Human serum albumin (HSA) exhibits excellent drug loading ability and is often used for biomimetic tumor delivery in multidrug nanocarriers.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!