Recent progress of microfluidic chips in immunoassay.

Microfluidic chip technology is a technology platform that integrates basic operation units such as processing, separation, reaction and detection into microchannel chip to realize low consumption, fast and efficient analysis of samples. It has the characteristics of small volume need of samples and reagents, fast analysis, low cost, automation, portability, high throughout, and good compatibility with other techniques. In this review, the concept, preparation materials and fabrication technology of microfluidic chip are described. The applications of microfluidic chip in immunoassay, including fluorescent, chemiluminescent, surface-enhanced Raman spectroscopy (SERS), and electrochemical immunoassay are reviewed. Look into the future, the development of microfluidic chips lies in point-of-care testing and high throughput equipment, and there are still some challenges in the design and the integration of microfluidic chips, as well as the analysis of actual sample by microfluidic chips.

Rapid Detection of DNA Methylation with a Novel Real-Time Fluorescence Recombinase-Aided Amplification Assay.

Researchers have conducted in-depth research on DNA methylation mechanism, which is related to various diseases such as deficiency of imprinted gene and occurrence of tumors. This study provides a novel rapid quantitative detection assay and real-time fluorescence recombinase-aided amplification assay (RAA) for DNA methylation. Firstly, specific sequence of methylation genes was chosen and primers and fluorogenic probe for RAA experiment were designed and synthesized. Lastly, these amplification products were proven by sequencing and analysis. Results showed that the amplification efficiency and template concentration of RAA had linear dependent (R² > 95%) when the concentration range was 4.64×108 copies/µL˜4.64×104 copies/µL. The test assay can also detect positive samples when the template concentration is below 4.64×104 copies/µL. Remarkably, the entire experiment process only takes 15-20 minutes, so it is beneficial for rapid bedside simple screening of some special DNA methylation sites, such as detection of resistance genes. In a word, this method has very great potential for diseases with DNA methylation in clinical settings, especially if methylation analysis needs to be done quickly and easily.

Two-Photon Fluorescent Nanomaterials and Their Applications in Biomedicine.

In recent years, two-photon excited (TPE) materials have attracted great attentions because of their excellent advantages over conventional one-photon excited (OPE) materials, such as deep tissue penetration, three-dimensional spatial selectivity and low phototoxicity. Also, they have been widely applied in lots of field, such as biosensing, imaging, photo-catalysis, photoelectric conversion, and therapy. In this article, we review recent advances in vibrant topic of two-photon fluorescent nanomaterials, including organic molecules, quantum dots (QDs), carbon dots (CDs) and metal nanoclus-ters (MNCs). The optical properties, synthetic methods and important applications of TPE nanomaterials in biomedical field, such as biosensing, imaging and therapy are introduced. Also, the probable challenges and perspectives in the forthcoming development of two-photon fluorescent nanomaterials are addressed.

Insulin-delivery methods for children and adolescents with type 1 diabetes.

Efforts directed toward restoring normal metabolic levels by mimicking the physiological insulin secretion, thereby ensuring safety, efficacy, minimal invasiveness and conveniences, are of great significance in the management of type 1 diabetes among children and adolescents. Regardless of the various technologies being discovered in addressing invasiveness and enhancing medication adherence in the management of type 1 diabetes, yet limited success had been observed among children and adolescents. The multiple daily subcutaneous insulin injections route using vial and syringe, and occasionally insulin pens, remain the most predictable route for insulin administration among children and adolescents. However, this route has been associated with compromised patient compliance, fear of injections and unacceptability, resulting in poor glycemic control, which promote the demand for alternative routes of insulin administration. Alternative routes for delivering insulin are being investigated in children and adolescents with type 1 diabetes; these include the hybrid closed-loop 'artificial pancreas' system, oral, inhalation, intranasal routes, and others. This review article explores the current advances in insulin-delivery methods that address the needs of children and adolescents in the treatment of type 1 diabetes.

Antitumor effect of hyaluronic-acid-modified chitosan nanoparticles loaded with siRNA for targeted therapy for non-small cell lung cancer.

Purpose: Nanoparticle (NP)-mediated targeted delivery of therapeutic genes or siRNAs to tumors has potential advantages. In this study, hyaluronic acid (HA)-modified chitosan nanoparticles (CS NPs-HA) loaded with cyanine 3 (Cy3)-labeled siRNA (sCS NPs-HA) were prepared and characterized. Methods: Human non-small cell lung cancer (NSCLC) A549 cells expressing receptor CD44 and tumor-bearing mice were used to evaluate the cytotoxic and antitumor effects of sCS NPs-HA in vitro and in vivo. Results: The results showed that noncytotoxic CS NPs-HA of small size (100-200 nm) effectively delivered the Cy3-labeled siRNA to A549 cells via receptor CD44 and inhibited cell proliferation by downregulating the target gene BCL2. In vivo experiment results revealed that sCS NPs-HA directly delivered greater amounts of Cy3-labeled siRNA to the tumor sites, resulting in the inhibition of tumor growth by downregulating BCL2, as compared to unmodified NPs loaded with siRNA (sCS NPs) and to naked Cy3-labeled siRNA. Conclusion: The HA-modified NPs based on chitosan could serve as a promising carrier for siRNA delivery and targeted therapy for NSCLC expressing CD44.