In recent years, specific detection of proteins is one of the hot issues about aptamers in proteomics. Here we reported a simple, sensitive and specific proximity-dependent protein assay with dual DNA aptamers. Thrombin was used as the model protein, and two aptamer probes with complementary sequence at 3′-end were designed for the two distinct epitopes of the protein. Association of the two aptamers with thrombin resulted in stable hybrids due to the proximity of 3′-end, then polymerase reaction was induced. The amount of obtained dsDNA was indicated using the fluorescence dye Sybr Green I. The results showed that the initial velocity of polymerase reaction had a positive correlation with concentration of thrombin. The advantages of this dual-aptamer-based approach included simple and flexible design of aptamer probes, high selectivity and high sensitivity. The detection limit was 6.9 pmol/L.

Mesenchymal stem cells (MSCs) mainly found in the bone marrow of adult mammals demonstrate unique capacities of differentiating into multiple cell lineages and undifferentiated MSCs are considered an ideal source of seed cells for cell therapy and tissue engineering. However, MSCs are heterogeneous and not abundant in bone marrow, and there are few specific markers for these cells currently. Therefore, new methods to isolate and characterize MSCs are urgently required. To address the problem, we successfully developed a high-specificity aptamer, called Apt-W2, to specifically recognize mouse bone marrow mesenchymal stem cells (mBMSCs). We synthesized Apt-W2 modified magnetic beads (Apt-W2-MBs) and used them as bait to fish out the MSCs from mouse bone marrow accurately by magnetic-activated cell sorting (MACS). Next, the sorted cells could break free from the Apt-W2-MBs by the competition of C-W2 (complementary strands of Apt-W2). As a result, the sorted cells were intact, and maintained the stem cell phenotype and good proliferative ability. Simultaneously, the sorted cells showed high pluripotency to differentiate into osteoblasts, chondrocytes, and adipocytes. More importantly, the Apt-W2-MB cocktail showed a fine capture performance for MSCs (∼88.33%). This new methodological approach can greatly facilitate MSC isolation efficiently and intactly, thereby enhancing the rate of in vitro differentiation of MSC-derived cells for the emerging field of tissue engineering and regenerative medicine. This new instrumental application of aptamers is an important innovation that achieved both high efficiency and nondestructive cell sorting, opening the door to novel cell sorting approaches.

The identification of functional ligand-membrane protein interactions under native conditions remains a major challenge in cancer biology. Using cell-systematic evolution of ligands by exponential enrichment, we identified a high-affinity DNA aptamer, CW06, against breast cancer cells. To precisely identify its native membrane target, we developed Aptamer-mediated Metabolic Glycan-labeling Proximity Hybridization (Apt-MGPH), which revealed the mitochondrial solute carrier SLC25A24 as the specific target. Unexpectedly, CW06 treatment upregulated SLC25A24 expression, disrupting methionine metabolism, depleting cytosolic SAM, and inducing G1 cell cycle arrest and senescence via the p21–HMGA1 axis. In mouse xenograft models, CW06 significantly inhibited tumor growth without affecting healthy tissues. Targeted degradation of SLC25A24 reverses these effects, confirming its regulatory role in the metabolism–senescence axis. Our study establishes Apt-MGPH as a robust tool for membrane target identification and highlights aptamer-induced target overexpression as a strategy for cancer therapy.

The survivability of strategic target in battlefield will be enhanced relying on the technology of electro optical jamming. Effective interference is occurrence in a certain wave band with conventional technology of smoke shadowing and lure. They can’t cope with the developing multimode precision guidance weapon. Foam is a new passive electro optical jamming technology of non-toxic and non-pollution. Visible, laser, infrared, millimeter-wave and centimeter-wave can all be weakened by foam. Foams were made through mixed gas by self-made foaming machine. The infrared extinction properties of foams cloud was studied using Fourier transform infrared spectrometer Bruker OPAG33. The factors which influencing the effects of infrared extinction of foams cloud were studied by experiments. It was observed that an intensive absorbing action was obtained in wave band of mid and far infrared. The diameter of foam and the thickness of cloud had an obvious effect on the transmittance of mid and far infrared. The reasons were analyzed by modeling the process of infrared signal propagating in foams cloud.