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Triclosan (TCS) is used in many health care products as a broad-spectrum antimicrobial and disinfectant agent; however, it is currently considered an emerging pollutant. The present study aimed to develop an analytical HPLC method coupled to a Diode Array Detector for the TCS determination in toothpaste. Method development involved the optimization of separation and sample preparation. For chromatographic separation optimization, different RP columns and aqueous mobile phases were addressed. The optimized chromatographic separation was achieved in around 3 minutes using a Symmetry C18 column at 30 °C, 0.6 mL/min flow-rate, and 225 nm wavelength detection. For toothpaste sample preparation optimization a response surface methodology using a Box-Behnken fractional factorial design was chosen. The sample treatment consisted of leaching 0.2 g sample by sonication for 7 minutes using 2 mL of MeOH. According to the International Conference on Harmonization (ICH, 1996/2005) and European Commission Decision 200/657/EC guidelines, the developed method was validated. The developed analytical method was found fast, economic, linear, sensitive, precise, and robust and allowed to quantify TCS in different healthcare products.

This research aims to study the thermal and emulsifying properties of the chan globulins (CG), which are the most abundant Osborne fraction of the seed of Hyptis suaveolens. In this sense, the calorimetric analysis indicated a cooperative behavior in thermal denaturation process with a denaturation temperature of 100.9°C and an enthalpy change of 124.6 kJ/mol for CG. Besides, strong gels (Gʹ ~7.5 × 105 Pa) were produced, with a gelation temperature of 80°C. Also, CG presented high surface activity with critical micelle concentration (CMC) of 0.3 mg/ml. The best emulsifying properties and colloidal stability were found at basic pH values and they were negatively influenced by the content of NaCl along a pH gradient. In conclusion, CG may be used as thermostable emulsifier at basic pH values (preferably without NaCl), and as a potential ingredient for protein‐rich gel formulations. Practical applications This work describes a simple and practical procedure to obtain CG at high yield (96%) and acceptable purity, which could be easily implemented without further costs and tedious chromatographic techniques. In addition, the high gelation capacity and strong gel formation for CG, make them suitable for formulation of protein‐based gels with potential application in the drug and food industry. CG also showed high emulsifying activity and emulsifying stability indexes, implying their promising use as a thermostable emulsifier at basic pH values. Finally, the incorporation of CG as food ingredient, is an alternative to other pseudocereals to expand the offer of gluten‐free food products for celiac consumers.