Simultaneous co-hydrothermal carbonization and chemical activation of food wastes to develop hydrochar for aquatic environmental remediation.

Locally generated food wastes, such as Arabic coffee ground (ACG) and olive oil cake (OOC) were converted to N-ACG: OOC - 3 hydrochar (HC) through simultaneous co-hydrothermal carbonization (Co-HTC) and chemical activation. The optimized ACG: OOC mass ratio (g: g) and chemical activation agent used were 1.2: 0.8 and 0.1 M HNO3, respectively. Spectroscopic analyses confirmed the dominance of oxygen-containing functionalities, whereas the X-ray diffraction pattern displayed peaks for both sucrose and cellulose on N-ACG: OOC - 3. The developed HC was tested for methylene blue (MB) and crystal violet (CV) adsorption in aqueous systems. Batch scale adsorption studies showed pH, initial concentration (Co), time (t), and temperature (T) dependent dye uptake. Maximum dye uptake was observed at pH 7, with 50 - 70% and 76 - 90 % CV and MB removal achieved within 15 min at varied Co: 50 - 200 mg/L. Adsorption was governed by multiple mechanisms, including hydrogen bonding, electrostatic interactions, π-π interactions, and n-π interactions. Dye elution was higher in ethanol (EtOH: C2H5OH), and CV elution (50.8%) was more significant than MB elution (14.8%).

Ultraperformance liquid chromatography-mass spectrometric method for determination of ampicillin and characterization of its forced degradation products.

In the current study, a rapid and sensitive UPLC-MS method has been developed for the quantitative analysis of ampicillin in pure and pharmaceutical formulations. Forced degradation analysis was performed and the stress degradation product thus obtained was characterized by mass spectrometry. The chromatographic separation was carried out using BEH C18 column (100 × 2.1 mm, 1.7 µm particle size) using a binary mobile phase mixture of 0.001% acetic acid in water and methanol (30:70). The flow rate was set at 0.3 mL min(-1). The total chromatographic analysis time for ampicillin was as short as 1.5 min. The detection and quantitation of the studied drug was carried out using positive electrospray ionization and selected ion reaction modes. The developed method was found to be linear over the concentration range of 0.25-3.0 µg mL(-1). The recovery studies suggest an excellent recovery of the procedure which was found in the range of 99.45-100.90%. The relative standard deviation range of the developed analytical procedure ranged from 1.98 to 2.67% in intraday studies and 2.38-2.98% in case of interday study. The limit of detection and limit of quantitation of the method were found to be 0.016 and 0.049 µg mL(-1), respectively.