Investigations of the Equilibrium Conditions in Plumes of Laser Desorbed Sinapic Acid with Amino Acid Analytes: Influence of Sample Preparation and Matrix to Analyte Ratio.

The equilibrium nature of a plume of laser desorbed material is examined through the application of a previously developed thermodynamic model to the ion signals observed in 337 nm MALDI mass spectra of mixtures of the matrix sinapic acid with the amino acids alanine, valine, isoleucine, and phenylalanine. Samples are prepared using both conventional dried-droplet and solvent-free methods for comparison. The relative yield of protonated amino acid is shown to increase as the amino acid gas-phase basicity increases for both sample preparation methods.

Hand-Fabricated CNT/AgNPs Electrodes using Wax-on-Plastic Platforms for Electro-Immunosensing Application.

Fabrication of inexpensive and flexible electronic and electrochemical sensors is in high demand for a wide range of biochemical and biomedical applications. We explore hand fabrication of CNT modified AgNPs electrodes using wax-on-plastic platforms and their application in electrochemical immunosensing. Wax patterns were printed on polyethylene terephthalate-based substrates to laydown templates for the electrodes.

Nitrogen Isotope Composition, Nitrogen Amount, and Fruit Yield of Tomato Plants Affected by the Soil-Fertilizer Types.

Tomatoes () are heavy nutrient feeding crops and require high amounts of nitrogen to maximize fruit production. The type of nitrogen applied and timing of fertilizer applications are important to reduce losses due to volatilization and leaching. Previous research suggested that nitrogen stable isotopes are a useful fingerprinting system for indicating if a crop has been grown with synthetic or organic nitrogen applications.

Effects of Natural Antioxidants on The Stability of Omega-3 Fatty Acids in Dog Food.

Introduction: The efficiency of five natural antioxidants (curcumin, cranberry, pomegranate, grape seed extract (GSE), and açai berry) in reducing lipid oxidation in dog food was compared to that of the synthetic antioxidant butylated hydroxyanisole (BHA).

Material And Methods: In two different experiments content parameters were measured after 12 days of storage at 55°C. In experiment one, the natural antioxidants were added at 0.

Simultaneous extraction, optimization, and analysis of flavonoids and polyphenols from peach and pumpkin extracts using a TLC-densitometric method.

Background: The use of medicinal plants has been reported throughout human history. In the fight against illnesses, medicinal plants represent the primary health care system for 60 % of the world's population. Flavonoids are polyphenolic compounds with active anti-microbial properties; they are produced in plants as pigments.

Employing response surface methodology for the optimization of ultrasound assisted extraction of lutein and β-carotene from spinach.

The extraction of lutein and β-carotene from spinach (Spinacia oleracea L.) leaves is important to the dietary supplement industry. A Box-Behnken design and response surface methodology (RSM) were used to investigate the effect of process variables on the ultrasound-assisted extraction (UAE) of lutein and β-carotene from spinach.