Accuracy of the system was investigated from % recovery of spiked TYR standard solutions and found to be in the range of 90-104%, which further verified the feasibility and reliability of our method applied in a complex environment. We anticipate this SERS-based immunoassay method to be applied to TYR detection in the clinical setting and to be extended to other promising related fields.Taking advantage of the superior biocompatibility, good stability in a wide pH and temperature range, as well as its strong affinity with DNA of hydroxyapatite (HAp), tetrahedral DNA nanostructures (TDNs) conjugated with AS1411 aptamer (anti-nucleolin overexpressed on tumor cell membranes) were employed as affinity ligands to construct a novel mono-dispersed HAp based probe with Gd3+ doping (Apt-TDNs-GdHAp) for MR imaging. The adsorption of TDNs on the nano-HAp surface facilely accomplished the construction of the Apt-TDNs-GdHAp probes. Meanwhile, the use of hydrophilic TDNs not only favored the phase-transfer from the oil phase to the aqueous phase, but also enhanced the mono-dispersion of this probe due to the well-ordered distribution of TDNs on the surface of nano-HAp. Moreover, Apt-TDNs-GdHAp probe with a better mono-dispersion and crystalinity achieved twice higher longitudinal relaxivity (r1 value) than that of GdHAp synthesized by microwave-assisted method (Microwave-GdHAp), exhibiting much more excellent T1-weighted imaging performance. With the introduction of TDNs, the stability and the tumor-targeting accessibility were also greatly improved, showing its great potential for further bio-applications.Cell-derived nanoparticles, so called Extracellular Vesicles (EVs), can reflect the physiological or pathological conditions of donor cells and can provide promising biomarkers for the non-invasive diagnosis of cancers. Size-based purification method is one of the common strategies for rapid extracting EVs from biosamples, but the downstream clinical studies still remain challenges in EV enrichment with high purity and high yield. Here, such challenges could be fulfilled through the development of an arrayed Exosome Purification and Operation System (Exo-POS) for efficiently isolating EVs from complex biofluids. Human urinary EVs with mean size of approximately 170 nm were isolated successfully from donors within 30 min, and the purification of individual samples were performable in parallel. Samples purified by Exo-POS showed detectable EV-specific biomarkers and less protein impurities than that by ultrafiltration method. The results also demonstrate the great purification ability of Exo-POS to discriminate between the EV-derived proteomic and genomic expressions of cancer patients and healthy controls. The developed platform can easily be adapted to retrieve EVs from biological samples for the downstream analysis, demonstrating its potential for both rapid clinical diagnosis and biomarker discovery.In this work, we proposed an electrochemical aptasensor for patulin (PAT) based on tetrahedral DNA nanostructures (TDNs) and thionine (Thi)-labeled Fe3O4 nanoparticles (Fe3O4NPs)/rGO signal amplification strategy. The rigid structure of TDNs could effectively improve the binding efficiency. Fe3O4NPs/rGO with excellent electrical conductivity and large specific surface area was used as a label material, which could load more Thi and accelerate electron transfer. Besides, the unique catalytic properties of Fe3O4NPs could achieve active signal amplification. Once PAT existed, PAT aptamer was released from the capture probe, thereby introducing Fe3O4NPs/rGO with Thi onto the electrode surface. Therefore, a noticeable increase in Thi current intensity was observed. Under the optimized conditions, the proposed aptasensor showed superior performance with a linear range from 5 × 10-8 to 5 × 10-1 μg mL-1 and a detection limit of 30.4 fg mL-1. The obtained sensor showed reliable specificity, stability and reproducibility, and was successfully applied to the determination of real samples.Herein, we report the development of sandwich type Surface Enhanced Raman Spectroscopy (SERS) immunosensor modified to be zwitterionic for the detection of soluble B7-H6 biomarker in blood serum from cervical cancer patients. Anti-fouling capture SERS substrate of biosensor based on gold (Au) thin film was modified with a self-assembled monolayer of zwitterionic l-cysteine to combat serum fouling and was then conjugated with NKp30 receptor protein to capture the B7-H6 biomarker in blood serum. The SERS nanoprobe based on spiky gold nanoparticles (AuNPs) was functionalized with ATP reporter molecule, that is stable at a wide range of pH, making the SERS signal reliable in complex media. Then, it was conjugated with anti-B7-H6 antibody forming the complex anti-B7-H6@ATP@AuNPs (i.e., SERS nanoprobe). The proposed immunosensor demonstrated high reproducibility for the quantitative detection of soluble tumor biomarker B7-H6 within the range of 10-10 M to 10-14 M with limit of detection (LOD) of 10-14 M or 10.8 fg mL-1, in the cancer patient serum, greatly exceeding (100 fold) the LOD of commercially available ELISA kits. Such low LOD is partially the result of zwitterionic modification which reduces the serum fouling by 55% compared to traditionally used BSA blocked capture substrates (i.e., control). Notably, this immunosensors demonstrated higher accuracy for detecting the B7-H6 biomarker in undiluted blood serum samples from cervical cancer patients and outperforms the currently available analytical techniques, making it reliable for point of care (POC) testing.Acid phosphatase is widely used as a clinical indicator because of its close correlation with a variety of diseases. Herein, a label-free and colorimetric sensing method for detecting the activity of acid phosphatase was constructed based on hollow mesoporous manganese dioxide nanospheres. The nanospheres exhibit superior oxidase-like property and can oxidize colorless 3,3′,5,5′-tetramethylbenzidine (TMB) to yellow TMB2+. Ascorbic acid from acid phosphatase-catalyzed hydrolysis of L-ascorbic acid-2-phosphate will inhibit the oxidization reaction, igniting vivid color variation. RVX-208 cell line On the basis of this obvious multicolor change, the visual detection of acid phosphatase was achieved. Compared with the single-color change, the multicolor colorimetric method is more conducive for naked-eye discrimination. The absorbance difference at 450 nm exhibits a linear relationship with the concentration of acid phosphatase ranging from 1.0 to 25 U L-1, with a detection limit as low as 0.45 U L-1. Acid phosphatase in human serum samples was successfully determined.