TEMED Enhanced Photoluminescent Imaging Detection of Proteins in Human Serum Using Quantum Dots after PAGE

Abstract

In this paper, the development of a novel enhanced photoluminescent (PL) imaging method for human serum proteins detection after polyacrylamide gel electrophoresis (PAGE) is described. Thioglycolic acid (TGA)-capped CdTe QDs and enhanced reagent tetramethylethylenediamine (TEMED) have been introduced, resulting in direct detection of various proteins in native polyacrylamide gels and expanded application scope to SDS gels. Some relatively low-abundance proteins such as Zinc-α(2)-glycoprotein (ZAG) and α(2)-HS-glycoprotein (α(2)-HSG) are easily detected by TEMED enhanced PL imaging and identified by MS and MS/MS techniques. In the present study, the PL imaging conditions such as QDs concentration, alkali concentration, and enhanced reagents are optimized and the possible mechanisms are analyzed. The sensitivity of TEMED enhanced PL imaging is satisfying, with a linear range of 11.7-375 ng for ferritin, comparing with 46.9-375 ng in CBB-R250 staining and 23.4-375 ng in direct PL imaging. As a novel PL imaging detection method that is simple, fast, and sensitive, it shows great analytical potential in proteome research and in biochemistry.

Macrophage polarization: convergence point targeted by Mycobacterium tuberculosis and HIV

“…Therefore, the switch toward a M2 Mɸ program might simply be part of a defensive mechanism by the host to control HIV-induced tissue damage since they participate in suppression of inflammation and promotion of tissue repair (Figure 1; Martinez et al, 2009; Murray and Wynn, 2011). Recently, a functional proteomic analysis of HIV-infected Mɸs in the presence of regulatory T cells showed that a deviation of M1 to M2 Mɸ program is associated with neuroprotection in the case of HIV-associated neurocognitive disorders, suggesting M2 Mɸs may curtail the M1 HIV polarized activity resulting in tissue damage (Huang et al, 2010). Conversely, the switch toward the M2 Mɸ program might also occur as an evasion strategy by HIV to promote its own survival.…”

Effects of N,N,N′,N′-tetramethylethylenediamine on the properties of CdTe quantum dots

“…35 The electronegative N atoms can bind onto the surface traps of the QDs to decrease the amount of defects and hence improve the PL intensity. 36,37 In addition, it is known that TEMED is a common reducing agent, and the structure of TEMED is similar to that of DTT, a molecule which is small enough to diffuse to the QDs interface. 38 Therefore, it is believed that TEMED is able to diffuse to the CdTe QDs interface, and can easily form a stable six-membered ring possessing an internal dinitrogen bond upon oxidation.…”

Quantum dot applications endowing novelty to analytical proteomics

“…Hahn et al demonstrated improved sensitivity using QDs as compared to a fluorescein dye for detection of Escherichia coli O157:H7 . Lidke et al tracked QD‐conjugated EGF interacting with a variety of visible fluorescent protein tagged erbB receptors in engineered cell lines.…”

“…The QD Western Blotting Kits have been rigorously designed to maximize sensitivity and minimize both nonspecific binding of the conjugate and for reducing membrane autofluorescence. Introduction of the QD system dramatically reduced the time and effort required for conventional western blot analysis . Two different QD western blotting protocols (CdSe QDs) were demonstrated for ultrasensitive detection of tracer proteins (Telomere‐associated proteins—telomeric repeat binding factor, a 56 kDa protein) and TRF1‐interacting nuclear protein 2 (40 kDa protein) directly in cell lysates .…”