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Author(s): Mutaz E. Salih [sup.1] [sup.2], Ahmad Aqel [sup.3], Babiker Y. Abdulkhair [sup.1] [sup.4], Munir S. Obbed [sup.3], Zeid A. ALOthman [sup.3], Yacine Badjah-Hadj-Ahmed [sup.3], Mohamad A. Abdulaziz [sup.1] Author [...], A home-made column (3.2 mm i.d., 100 mm length) was prepared in which glycidyl polymethacrylate was used. The optimum value of the initiator corresponded to 5 mg/mL. The column morphology was characterized by scanning electron microscopy. The permeability was evaluated using acetonitrile and water as a mobile phase and uracil as an unretained substrate. A simple and economical reversed-phase HPLC method has been developed for the simultaneous estimation of paracetamol and chlorzoxazone in their pharmaceutical formulations. Components were determined using a UV detector at 270 nm. The mobile phase was composed of 1% formic acid solution and acetonitrile (65/35, v/v); 0.7 mL/min flow rate and 5.0 [micro]L injection volume were used. Peak resolution was 1.96. All findings allow concluding that the prepared stainless steel conventional HPLC column and the novel validated method are applicable for quality control and routine analysis.

In the last decade, worldwide illegal production and consumption of methamphetamine (MA) has dramatically increased. MA is chiral and its two enantiomers have different biological properties, the S isomer having higher stimulating and addictive effects and therefore important to determine the enantiomeric ratio in drug seizures. The chiral separation and determination of R and S-MA may be used for characterization of the seized samples and elucidation of the illicit method of preparation. The present article aims to investigate the enantiomeric distribution of R and S methamphetamine in a series of seized samples. The enantioseparation was achieved first by derivatization of MA using L-TPC followed by separation of the resulting diastereomers using GC-MS. The optimized chromatographic method allowed baseline separation of the peaks with a resolution parameter of 2.16. While the total concentration of methamphetamine in the seized samples was between 15.09 and 213.20 mg/g, all investigated samples showed the presence of both R and S enantiomers, with a higher content of S-MA. The enantiomeric excess (ee%) was calculated to characterize each sample, the obtained values were in the range 55.27–92.38%. The results demonstrated that the seized samples originated from different batches and most likely from a stereospecific synthetic route. [ABSTRACT FROM AUTHOR]

The formation of bacterial biofilms is a severely encountered problem in clinical and industrial settings. Most of the naturally occurring bacterial strains are capable of forming mono or mixed biofilms. In this study, we evaluated the potentiality of three clinically relevant species in forming mono and mixed biofilms over glass surface. In addition, we also appraised the efficiency of bacteriophages in alleviating preformed mono and mixed biofilm. Our initial study focused on the ability of Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa in forming biofilm on glass cover slip. All the three strains were able to form mono biofilm, although at varying intensities. Interestingly, E. coli inhibited the formation of S. aureus biofilm in a mixed culture. Specific bacteriophages ɸ44AHJD and ɸX174 completely disrupted S. aureus and E. coli preformed biofilm structure after 72 hr of incubation. However, addition of either of the bacteriophage to the mixed E. coli–S. aureus promoted the formation of biofilm by the alternate strain that was not affected by the phage. Our findings elicit the potentiality of common bacterial strains in forming biofilms on smooth glass surface. In addition, these results are very promising for the development of effective drugs using intact bacteriophages for the removal of complicated bacterial biofilms formed in clinically relevant glass surfaces. The observations further complemented the earlier finding of competitive inhibition of S. aureus biofilm development by E. coli. [ABSTRACT FROM AUTHOR]