Synthesis of N-doped Carbon Quantum Dots as an Effective Fluorescent Sensor of Fe Ions and a Potent Antibacterial Agent.

In this study, a simple and efficient method for synthesizing nitrogen-doped carbon quantum dots (N-CQDs) has been developed through a one-step hydrothermal process using hedyotis diffusa willd. The morphology, chemical composition, and optical properties of the resulting N-CQDs were thoroughly characterized. The synthesized N-CQDs exhibited a spherical shape with an average particle size of 4.

A General Strategy to Rapid and Sensitive Determination of Five High Boiling Point Solvents in Pharmaceuticals by RP-HPLC Combined with Precipitation Method.

The difficulty on determination of high boiling point solvents, always exist due to their low vapor pressure in headspace (HS) vial. What's worse, the commonly used GC diluents, such as N, N-dimethylacetamide, 1,3-dimethyl-2-imidazolidinone, dimethyl sulfoxide, N, N-dimethylformamide and N-methylpyrrolidone are often remained in HS instrument after frequent injection into HS, thus would result in terrible positive interference problem. In this work, a fast and sensitive HPLC method in combination with a sample precipitation method, was proposed for the determination of above five high boiling point solvents in drug substances within 14.

The Development of One New Normal Phase Liquid Chromatography Method and Thermodynamic Investigation of Olodaterol Hydrochloride Enantiomer.

In order to improve and replace the enantiomer method outlined in the olodaterol hydrochloride draft monograph (From the European Pharmacopoeia forum), one new, simple, and fast enantioselective normal phase high-performance liquid chromatography chiral method was developed on polysaccharide-based Chiral MX (2) (4.6 × 250 mm, 5 μm) column. n-Hexane, ethanol, and diethylamine in the ratio of 40:60:0.

ViboPneumo: A Vibratory-Pneumatic Finger-Worn Haptic Device for Altering Perceived Texture Roughness in Mixed Reality.

Extensive research has been done in haptic feedback for texture simulation in virtual reality (VR). However, it is challenging to modify the perceived tactile texture of existing physical objects which usually serve as anchors for virtual objects in mixed reality (MR). In this paper, we present ViboPneumo, a finger-worn haptic device that uses vibratory-pneumatic feedback to modulate (i.

Degradation Mechanism Study for Secondary Degradants in Rosuvastatin Calcium and Determination of Degradant Acetaldehyde Using Static Headspace Gas Chromatography Coupled with Matrix Precipitation.

During the development of headspace gas chromatography (HSGC) method for assessing residual solvents in rosuvastatin calcium (RSV) drug substance, acetaldehyde (AA) was detected in obtained chromatograms, with a calculated concentration of up to 226 ppm. After a series of experiments, it was established that acetaldehyde originates from matrix interference due to direct degradation of Imp-C, which is accompanied by the formation of impurity at relative retention time (RRT) 2.18, without the involvement of impurity at RRT 2.

PropelWalker: A Leg-Based Wearable System With Propeller-Based Force Feedback for Walking in Fluids in VR.

There has been an increasing focus on haptic interfaces for virtual reality (VR), to support a high-quality touch experience. However, it is still challenging to haptically simulate the real-world walking experience in different fluid mediums. To tackle this problem, we present PropelWalker, a pair of calf-worn haptic devices for simulating the buoyancy and the resistant force when the human's lower limbs are interacting with different fluids and materials in VR.

Late-onset riboflavin-responsive multiple acyl-CoA dehydrogenase deficiency (MADD): case reports and epidemiology of ETFDH gene mutations.

Background: Multiple acyl-CoA dehydrogenase deficiency (MADD) is a riboflavin-responsive lipid-storage myopathy caused by mutations in the EFTA, EFTB or ETFDH genes. We report a Chinese family of Southern Min origin with two affected siblings with late-onset riboflavin-responsive MADD due to a homozygous c.250G > A EFTDH mutation and review the genetic epidemiology of the c.

Magnetic relaxation switch and colorimetric detection of thrombin using aptamer-functionalized gold-coated iron oxide nanoparticles.

We describe a sensitive biosensing system combining magnetic relaxation switch diagnosis and colorimetric detection of human α-thrombin, based on the aptamer-protein interaction induced aggregation of Fe(3)O(4)@Au nanoparticles. To demonstrate the concept, gold-coated iron oxide nanoparticle was synthesized by iterative reduction of HAuCl(4) onto the dextran-coated Fe(3)O(4) nanoparticles. The resulting core-shell structure had a flowerlike shape with pretty narrow size distribution (referred to as "nanorose").

A miniature chip for protein detection based on magnetic relaxation switches.

A miniature multi-sample chip for protein detection with a bench-top magnetic resonance imager was created on the basis of magnetic relaxation switches. The chip was assessed with two protein systems. Both qualitative and quantitative results for the target proteins were obtained by image analysis and relaxation time measurement, respectively.

Rational strategy of magnetic relaxation switches for glycoprotein sensing.

A rational strategy of magnetic relaxation switches was proposed here to detect a(1)-acid glycoprotein (AGP), an acute phase a-globulin plasma glycoprotein. The assay was based on the relaxation time change between the aggregation of magnetic nanoparticles with concanavalin A and the redispersion with AGP, which can avoid the prozone effect and improve the detection accuracy. The assay was an easy and efficient method with two mixing steps and one measurement step, showing a detection limit of 0.

A smart surface in a microfluidic chip for controlled protein separation.

The smart surface created in a microfluidic chip has shown the capability of adsorbing and releasing proteins under electrical control. The inner surface of the chip channel was first coated by a thin layer of Au through sputtering and was subsequently modified with loosely packed self-assembled monolayers (SAMs) of thiols with terminal carboxylic or amino groups. Upon application of an external electric potential to the gold substrate, reversible conformational transformation between "bent" and "straight" states for the anchored mercapto chains could be modulated, through the electrostatic effect between the ionized terminal groups and the charged gold substrate.