Abstract
Polymeric matrix tubular membrane sensors incorporating poly(vinyl chloride) matrix, o‐nitrophenyloctylether (o‐NPOE) plasticizer and either dinonylnaphthalene sulfonate (DNNS) or tridodecylammonium chloride (TDMAC) ionophore are prepared and electrochemically evaluated for determination of carrageenan polyion. These sensors are used for monitoring potentiometric titration of carrageenan with protamine titrant. Carrageenan at the concentration levels of 0.2–1.5% (m/m) in a variety of food products (e.g., cream, chocolate, caramel, ice cream, and salad dressing) are satisfactory determined. Results agree fairly well with nominal values are obtained and confirmed by recovery experiments of spiked samples. The method has several advantages over all previously reported methods in being more simple, accurate and applicable for routine analysis of real samples without prior treatment.