Determination of biogenic amines in chicken, beef, and mutton by dansyl chloride microwave derivatization in Malaysia.

In this study, an improved dansyl-chloride derivatization technique using a microwave synthesizer was used for the qualitative and quantitative analyses of biogenic amine in the fresh meat samples. The derivatization technique was optimized in terms of temperature, reaction time, and spinning speed. The derivatization method together with a validated reversed-phase HPLC-DAD method was used for the determination of biogenic amines in chicken, beef, and mutton sold in the wet market. The results of the analyses showed that tryptamine, putrescine, and histamine were generally detected in all the three types of meat. Higher levels of histamine were found in chicken and beef. However, low levels of histamine were observed in mutton. Tyramine was either detected low or moderate in all the three types of meat. The biogenic amines of the fresh meat sold in the wet market is generally higher than the reported values. The mechanisms of biogenic amines-dansyl-chloride formation were investigated and proposed. PRACTICAL APPLICATION: The biogenic amine derivatization method was improved. The improved derivatization method can be potentially used for various food products beside meats for routine biogenic amine analyses due to its fast analysis time and simplicity. High levels of biogenic amines were generally found in the meat sold in the wet markets. However, proper handling of the raw meat can reduce the risk of infection.

Therapeutic plasma exchange (TPE) for semi-critical neurology presentations in a non-acute neurology set-up: clinical practice and challenges.

INTRODUCTION: Therapeutic plasma exchange (TPE) for semi-critical neurological manifestations can be managed in non-acute setting instead of critical care unit. In 2014, we established a non-acute neurology TPE unit for semi-critical haemodynamically stable patients. In this study, we aimed to evaluate the technical and safety parameters from the first 3 years of service. MATERIALS AND METHODS: We analysed prospectively collected TPE data for patients treated with centrifugation TPE at our non-acute neurology TPE unit in Kuala Lumpur Hospital between May 2015 and June 2018. RESULTS: A total of 245 TPE procedures were performed in 55 patients for nine neurological indications, predominantly the central nervous system (79%). Twenty four per cent (n=13) had category I and 73% (n=40) had category II indication (American Society for Apheresis (ASFA) 2019). Others (4%) were not in ASFA indications. Neuromyelitis optica spectrum disorders accounted for half (51%) of the total patients. Twenty-three (41.8%) patients experienced adverse events, with hypotensive episodes being the the most common (n=12/55, 21.8%). Five (9.1%) patients had catheter-related blood stream infection, correlating with higher exchange plasma volume (p=0.023). Symptomatic hypocalcaemia was less common (n=5/55, 9.1%) and allergic reaction to human albumin was rare (n=1/55, 1.8%). Four technical errors detected. Three involved centrifugation sets manufacturing defects and one involved error in centrifugation set installation. Seven (2.9%) procedures were terminated: 5 for adverse effects and 2 for technical errors. CONCLUSION: Performing TPE among semi-critical patients with neurology manifestations in basic non-acute set-up proved safe, with predictable complications. This set-up reduced the reliance on critical care services for TPE procedures.