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The enantioseparation of four stereoisomers of palonosetron hydrochloride (PALO) by capillary zone electrophoresis using high concentration β-CD as chiral selector was described in this study. For optimization of the method of enantioseparation, several parameters such as β-CD concentration, separation buffer pH and concentration, the types and concentration of organic modifiers, and the applied voltage were evaluated. The optimum conditions were obtained as follows: 30 mmol L -1 NaH2PO4 (pH 3.0) containing 150 mmol L -1 β-CD and 10% (v/v) methanol with an applied voltage of 15 kV. Under these conditions, baseline separation of the four PALO stereoisomers was achieved within 35 min, and the reproducibility (expressed as relative standard deviation, RSD) of the migration times and the peak areas were below 0.5, 2.5% (intra-day), and 1.9, 4.4% (inter-day), respectively. hydrochloride, is a pharmacologically distinct and highly selective, secondgeneration 5-hydroxytryptamine type-3 (5-HT3) receptor antagonist approved for prevention of chemotherapy-and radiotherapy-induced nausea and vomit (CINV) after highly emetogenic chemotherapy. 1-4 Chemotherapy-and radiotherapyinduced nausea and vomit will have a series of related complications if they lack control; these are the most feared adverse reactions in cancer patients. 5-HT3 receptor antagonized mainly through competing to block the release of 5-HT and 5-HT3 receptor-binding of digestive tract mucosa in order to have a role in anti-vomit treatment.Chiral drugs include a large proportion of drugs at present; they generate different pharmacological effects through combining with different stereo structure molecules in the body in the processes of drug absorption, distribution, metabolism and excretion. Consequently, the separation and measurement of chiral drugs have great significance in the pharmacokinetics, pharmacological and toxicological mechanisms as well as in quality control of chiral drugs. Palonosetron hydrochloride contains two chiral centers and four stereoisomers: (3aR, 2R), (3aS, 2S), (3aR, 2S) and (3aS, 2R), among which only (3aS, 2S) possesses pharmacological activity. 5 Therefore, it is necessary to establish an appropriate enantiomeric separation method for PALO.Capillary electrophoresis (CE) is now recognized as a powerful tool for enantioseparation due to its high separation efficiency, low operational cost, simplicity and versatility. [6][7][8][9][10] In CE, the enantioselectivity is based on the chiral selector, which is dissolved in the running buffer. During the last decade, various types of chiral selectors, such as cyclodextrins (CDs) and their derivatives, 11,12 crown ethers, 13 chiral surfactants, 14,15 polysaccharides, 16,17 macrocyclic antibiotics, 18 proteins, 19 and metal complexes 20,21 have been widely used in CE. Among them, CDs and their various derivatives are the most popularly used chiral selectors with about 90% of the applications. 10 CDs, which obtained from amylum enzymatic conversion, can form inclusion compounds with many ...

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Stretchable electronic devices must conform to curved surfaces and display highly reproducible and predictable performance over a range of mechanical deformations. Mechanical resilience in stretchable devices arises from the inherent robustness and stretchability of each component, as well as from good adhesive contact between functional and structural components. In this work, we combine bench-top thin film structuring with solvent assisted lift-off transfer to produce flexible and stretchable multi-material thin film devices. Patterned wrinkled thin films made of gold (Au), silicon dioxide (SiO2), or indium tin oxide (ITO) were produced through thermal shrinking of pre-stressed polystyrene (PS) substrates. The wrinkled films were then transferred from the PS to poly(dimethylsiloxane) (PDMS) substrates through covalent bonding and solvent-assisted dissolution of the PS. Using this approach, different materials and hybrid structures could be lifted off simultaneously from the PS, simplifying the fabrication of multi-material stretchable thin film devices. As proof-of-concept, we used this structuring and transfer method to fabricate flexible and stretchable thin film heaters. Their characterization at a variety of applied voltages and under cyclic tensile strain showed highly reproducible heating performance. We anticipate this fabrication method can aid in the development of flexible and stretchable electronic devices.

Antifouling polymer coatings that are simple to manufacture are crucial for the performance of medical devices such as biosensors. “Grafting-to”, a simple technique where presynthesized polymers are immobilized onto surfaces, is commonly employed but suffers from nonideal polymer packing leading to increased biofouling. Herein, we present a material prepared via the grafting-to method with improved antifouling surface properties and intrinsic localized surface plasmon resonance (LSPR) sensor capabilities. A new substrate shrinking fabrication method, Graft-then-Shrink, improved the antifouling properties of polymer-coated Au surfaces by altering graft-to polymer packing while simultaneously generating wrinkled Au structures for LSPR biosensing. Thiol-terminated, antifouling, hydrophilic polymers were grafted to Au-coated prestressed polystyrene (PS) followed by shrinking upon heating above the PS glass transition temperature. Interestingly, the polymer molecular weight and hydration influenced Au wrinkling patterns. Compared to Shrink-then-Graft controls, where polymers are immobilized post shrinking, Graft-then-Shrink increased the polymer content by 76% in defined footprints and improved the antifouling properties as demonstrated by 84 and 72% reduction in macrophage adhesion and protein adsorption, respectively. Wrinkled Au LSPR sensors had sensitivities of ∼200–1000 Δλ/ΔRIU, comparing favorably to commercial LSPR sensors, and detected biotin–avidin and desthiobiotin–avidin complexation in a concentration-dependent manner using a standard plate reader and a 96-well format.