Behaviour of polydiacetylene vesicles under different conditions of temperature, pH and chemical components of milk

Abstract

Blue polydiacetylene vesicles were studied with regard to their behaviour under variations in storage temperature, heating, potentiometric titration and in the presence of chemical components of milk, to evaluate their application as a sensor in the food industry. Vesicles were prepared using 10,12-pentacosadienoic acid (PCDA)/1,2-dimyristoyl-sn-glycero-3-phosphatidylcholine (DMPC). Their changes were monitored using UV-Vis absorption. Temperatures not exceeding 25°C did not cause colour change in PCDA/DMPC vesicles for a period of up to 60days of storage. Heating for 10min at 60 and 90°C, exposure to pH higher than 9.0 and the simulant solutions of the whey proteins, β-lactoglobulin and α-lactalbumin, promoted colour change from blue to red for the vesicles studied. The effects of routine factors on the characteristics and stability of polydiacetylene vesicles is important in defining the parameters related to their application as a sensor for the food industry.

Colorimetric detection of influenza A (H1N1) virus by a peptide-functionalized polydiacetylene (PEP-PDA) nanosensor

“…3). [49][50][51][52][53] As the temperature increased, the dynamics of all segments within the PDA nanosensors increased, resulting in a shi in the absorption spectrum to a high-energy region and a change in the color transition from blue to red due to conformational change. As shown in Fig.…”

Stability and sensitivity of polydiacetylene vesicles to detect Salmonella

“…This phenomenon is called Thermochromism and it could affect the PDA particle size to some extent. On the other hand, the temperature could also provide the energy necessary for changes in the PDA chain to become more stable at 32.5 • C and consequently causes changes in optical absorption and the color transition [2][3][4][5]7,8,19].…”

“…Among the conjugated polymers reported to date, PDAs are one of particular interest because they can change color from blue to red in response to external stimuli and can be auto-arranged in liposome assembly [2][3][4][5][6][7][8]; these characteristics could be manipulated by lipid insertion modifying biointerfacial interactions and it could be utilized in sensing technologies to improve biosensors [9,10]. The polydiacety…”

Polydiacetylene sensor interaction with food sanitizers and surfactants

“…Also, it can be argued that PDA vesicles would be more properly called an ''amphiphile" rather than a lipid, since it is not of biological origin and that liposomes are composed specifically of phospholipids rather than fatty acid derivatives. External stimuli such as heat, pH, mechanical stress and chemical solvents (de Oliveira, Soares, Fontes, de Oliveira, & Maradini Filho, 2012;Jelinek & Kolusheva, 2001;Okada, Peng, Spevak, & Charych, 1998) leads to rapid colour change from the initial intense blue colour to red. It is believed that stress induced twisting of the highly planar backbone lead to the colour change of PDA vesicles (Berman & Charych, 1999).…”