Tumor-targeted glycogen nanoparticles loaded with hemin and glucose oxidase to promote tumor synergistic therapy

Strategies which are used to address the low levels of intracellular hydrogen peroxide and the development of biocompatible catalysts still need to be fulfilled in tumor chemodynamic therapy. Therefore, a novel tumor-targeted glycogen-based nanoparticle system (GN/He/GOx/HA) was developed to co-deliver hemin (He) and GOx, which can self-supply glucose formed upon degradation of glycogen by α-glycosidase in the lysosome environment, in order to achieve synergistic antitumor therapy. Hyaluronic acid (HA) was selected as the outer shell to protect the activity of GOx, and to increase the uptake by tumor cells via CD44 receptor-mediated endocytosis. GN/He/GOx/HA NPs had a good stability in the blood circulation, but fast release of the therapeutic cargos upon intracellular uptake. Hemin had a cascade catalytic reaction with GOx. Furthermore, GN/He/GOx/HA NPs had the strongest cytotoxicity in Hela cells in a glucose concentration dependent manner. The NPs could efficiently produce reactive oxygen species in tumor cells, resulting in a decrease in the mitochondrial membrane potential and apoptosis of tumor cells. The in vivo results showed that the drug-loaded nanoparticles had good safety, biocompatibility, and efficacious antitumor effect. Therefore, the glycogen-based nanoparticle delivery system provides potential application for self-enhancing CDT, which can be used for effective antitumor therapy.

Skillfully collaborating chemosynthesis with GOx-enabled tumor survival microenvironment deteriorating strategy for amplified chemotherapy and enhanced tumor ablation

The satisfactory efficient tumor treatment and complete tumor ablation using a mono-therapeutic approach are limited owing to the tumor complexity, diversity, heterogeneity and the multiple pathways involved in tumor pathogenesis. Herein, novel, intelligent and tumor microenvironment (TME)-responsive biotin/R8 peptide co-modified nanocarriers (BRNC) loading paclitaxel (PTX)/glucose oxidase (GOx) were constructed. GOx could catalyze the oxidation of intracellular glucose to gluconic acid and poisonous H2O2 to cause the deterioration of the tumor survival microenvironment, simultaneously achieving starvation and oxidation therapy. The acidic amplification during the GOx-mediated oxidation progress could in turn accelerate the cleavage of the acid-degradable hydrazone bond, promoting the deep penetration of nanocarriers into tumors. Even better, the aforementioned two aspects further increased the tumors' sensitivity to chemotherapeutic agents. Both in vitro and in vivo investigations indicated that the co-administration of GOx-BRNC and PTX-BRNC can remarkably improve the therapeutic efficacy and reduce side effects through the high-specific tumor targeting multimodal synergistic starvation/oxidation/chemotherapy, which would be a promising strategy for the next generation cancer therapy.

Electrochemical sensing of blood proteins for mild traumatic brain injury (mTBI) diagnostics and prognostics: towards a point-of-care application

Traumatic Brain Injury (TBI) being one of the principal causes of death and acquired disability in the world imposes a large burden on the global economy. Mild TBI (mTBI) is particularly challenging to assess due to the frequent lack of well-pronounced post-injury symptoms. However, if left untreated mTBI (especially when repetitive) can lead to serious long-term implications such as cognitive and neuropathological disorders. Computer tomography and magnetic resonance imaging commonly used for TBI diagnostics require well-trained personnel, are costly, difficult to adapt for on-site measurements and are not always reliable in identifying small brain lesions. Thus, there is an increasing demand for sensitive point-of-care (POC) testing tools in order to aid mTBI diagnostics and prediction of long-term effects. Biomarker quantification in body fluids is a promising basis for POC measurements, even though establishing a clinically relevant mTBI biomarker panel remains a challenge. Actually, a minimally invasive, rapid and reliable multianalyte detection device would allow the efficient determination of injury biomarker release kinetics and thus support the preclinical evaluation and clinical validation of a proposed biomarker panel for future decentralized in vitro diagnostics. In this respect electrochemical biosensors have recently attracted great attention and the present article provides a critical study on the electrochemical protocols suggested in the literature for detection of mTBI-relevant protein biomarkers. The authors give an overview of the analytical approaches for transduction element functionalization, review recent technological advances and highlight the key challenges remaining in view of an eventual integration of the proposed concepts into POC diagnostic solutions.

Catalytic hairpin assembly mediated liposome-encoded magnetic beads for signal amplification of peroxide test strip based point-of-care testing of ricin

Herein, we propose a new peroxide test strip (PTS) based point-of-care testing (POCT) method to detect ricin B-chain qualitatively and quantitatively by using catalytic hairpin assembly (CHA) mediated liposome-encoded magnetic beads for signal amplification. The sensitivity of this PTS based POCT method was improved significantly because it combined CHA signal amplification and liposome-based signal amplification.

Translating in vitro diagnostics from centralized laboratories to point-of-care locations using commercially-available handheld meters

There is a growing demand for high-performance point-of-care (POC) diagnostic technologies where in vitro diagnostics (IVD) is fundamental for prevention, identification, and treatment of many diseases. Over the past decade, a shift of IVDs from the centralized laboratories to POC settings is emerging. In this review, we summarize recent progress in translating IVDs from centralized labs to POC settings using commercially available handheld meters. After introducing typical workflows for IVDs and highlight innovative technologies in this area, we discuss advantages of using commercially available handheld meters for translating IVDs from centralized labs to POC settings. We then provide comprehensive coverage of different signal transduction strategies to repurpose the commercially-available handheld meters, including personal glucose meter, pH meter, thermometer and pressure meter, for detecting a wide range of targets by integrating biochemical assays with the meters for POC testing. Finally, we identify remaining challenges and offer future outlook in this area.

A new voltammetric immunosensing platform for prostate-specific antigen based on the Cu(ii)-pyrophosphate ion chelation reaction

An electrochemical immunoassay was designed to detect prostate-specific antigenviapyrophosphatase-hydrolysed Cu(ii)-coordinated pyrophosphate ion with the capture of the releasing Cu(ii) ion.