For the first time, we present an original sensing strategy with an ultra-wide detection window from 17 nM to 20 mM to detect SCN- ions. Initially, we investigated the clustering and optical properties of noble metal sol nanoparticles (NPs) due to the competitive interaction of thiocyanate ions (SCN-) and cetyltrimethylammonium bromide (CTAB) under weak acidic conditions, and found that different dimensions and scales of nanoclusters containing the alkyne-embedded Au@Ag NPs and relatively small Ag NPs could be achieved by the mediation of CTAB through electrostatic forces and hydrophobic interaction, in which SCN- could be covalently bonded with the silver surface of NPs to form a compact molecular layer (-Ag-S-C[triple bond, length as m-dash]N), and CTAB could only occupy remaining sites. In this process, we found that SCN- always runs counter to CTAB and tends to dissolve nanoclusters, so that they occupy the exposed surface of NPs in nanoclusters rather than the binding sites of one another.
View Article and Find Full Text PDFEstablishing an accurate, simple, and rapid serodiagnosis method aiming for specific cancer antigens is critically important for the clinical diagnosis, therapy, and prognostication of cancer. Currently, surface-enhanced Raman scattering (SERS) readout techniques challenge fluorescent-based detection methods in terms of both optical stability and more importantly multiple detection capability, which become more desirable for clinical diagnostics. We thus started using an interference-free mixing SERS emission (m-SERS) readout to simultaneously indicate, for the first time, three specific liver cancer antigens, including α-fetoprotein (AFP), carcinoembryonic antigen (CEA), and ferritin (FER), even in one clinical serum sample.
View Article and Find Full Text PDFHere, a completely new readout technique, so-called "Click" SERS, has been developed based on Raman scattered light splice derived from nanoparticle (NP) assemblies. The single and narrow (1-2 nm) emission originating from triple bond-containing reporters undergoes dynamic combinatorial output, by means of controllable splice of SERS-active NPs analogous to small molecule units in click chemistry. Entirely different to conventional "sole code related to sole target" readout protocol, the intuitional, predictable and uniquely identifiable "Click" SERS is relies on the number rather than the intensity of combinatorial emissions.
View Article and Find Full Text PDFThe first appeal of clinical assay is always accurate and rapid. For alkaline phosphatase (ALP) monitoring in medical treatment, a rapid, reliable surface-enhanced Raman scattering (SERS) test kit is designed based on a "hot spots" amplification strategy. Consisting of alkyne-tagged Au nanoparticles (NPs), Ag, and enzyme substrate, the packaged test kit can achieve one-step clinical assay of ALP in human serum within several minutes, while the operation is simple as it directly inputs the sample into the test kit.
View Article and Find Full Text PDFThe alkyne tags possess unique interference-free Raman emissions but are still hindered for further application in the field of biochemical labels due to its extremely weak spontaneous Raman scattering. With the aid of computational chemistry, herein, an alkyne-modulated surface-enhanced Raman scattering (SERS) palette is constructed based on rationally designed 4-ethynylbenzenethiol derivatives for spectroscopic signature, Au@Ag core for optical enhancement and an encapsulating polyallylamine shell for protection and conjugation. Even for the pigment rich plant cell (e.
View Article and Find Full Text PDFNasopharyngeal carcinoma (NPC) is a highly prevalent disease in Southeast Asia and its prevalence is clearly affected by genetic background. Various theories have been suggested for its high incidence in this geographical region but to these days no conclusive explanation has been identified. Chromosomal imbalances identifiable through comparative genomic hybridization may shed some light on common genetic alterations that may be of relevance to the onset and progression of NPC.
View Article and Find Full Text PDFObjective: To study the correlation of prostate-specific membrane antigen (PSMA) and prostate-specific antigen (PSA) expression with Gleason score of prostate carcinoma.
Methods: Monoclonal antibodies against epitopes of PSMA extracellular domain were prepared, with which the expression of PSMA of prostate carcinoma (PC) was determined by immunohistochemical staining. Correlation of its expression with Gleason score of PC was statistically analyzed, and compared with that of PSA.
Objective: To investigate the effect of HER2/neu overexpression on the wild p53 gene expression, cell proliferation and sensitivity to gamma-irradiation via phosphatidylinositol 3-kinase (PI3K) pathway in human breast cancer cell MCF7.
Methods: Lipofectin-mediated gene transfection method was used to transfer HER2/neu into MCF7 cells. Expression of HER2/neu, p53, Akt and p-Akt protein after PI3K pathway inhibitor LY294002 treatment was determined by Western blot.
Overexpression and activation of HER-2/neu (also known as c-erbB-2), a proto-oncogene, was found in about 30% of human breast cancers, promoting cancer growth and making cancer cells resistant to chemo- and radio-therapy. Wild-type p53 is crucial in regulating cell growth and apoptosis and is found to be mutated or deleted in 60-70% of human cancers. And some cancers with a wild-type p53 do not have normal p53 function, suggesting that it is implicated in a complex process regulated by many factors.
View Article and Find Full Text PDFObjective: To evaluate the effect of HER2/neu overexpression on wild p53 protein expression and to delineate the related signal pathways.
Methods: Lipofectin method was used to transfer HER2/neu into human breast tumor cell line MCF7. Overexpression of HER2/neu was then determined by Western blot.