The vesicle of didodecyldimethylammonium bromide (DDAB) which containedtetrathiafulvalene (TTF) was mixed with xanthine oxidase, and the mixture was cast on the pyrolyticgraphite electrode. The lipid films were used t...The vesicle of didodecyldimethylammonium bromide (DDAB) which containedtetrathiafulvalene (TTF) was mixed with xanthine oxidase, and the mixture was cast on the pyrolyticgraphite electrode. The lipid films were used to supply a biological environment resemblingbiomembrane on the surface of the electrode. TTF was used as a mediator because of its highelectron-transfer efficiency. A novel xanthine biosensor based on cast DDAB film was developed. Theeffects of pH and operating potential were explored for optimum analytical performance by using theamperometric method. The response time of the biosensor was less than 10 s. The detection limit ofthe biosensor was 3.2 x 10^(-7) mol/L and the liner range was from 4 x 10^(-7) mol/L to 2.4 x10^(-6) mol/L.展开更多
Hen egg white lysozyme(HEWL)is a food-derived antimicrobial protein,exhibiting bacteriolytic activity against several bacteria including foodborne enteric pathogens.It has been approved for using in food,pharmacologic...Hen egg white lysozyme(HEWL)is a food-derived antimicrobial protein,exhibiting bacteriolytic activity against several bacteria including foodborne enteric pathogens.It has been approved for using in food,pharmacological and therapeutic applications.However,using HEWL through the ingestion is still a challenge due to its poor stability and low bioavailability in the gastro-intestinal tract(GIT).Herein,liposomes incorporating with dimethyl dioctadecyl ammonium bromide(DDAB)were fabricated to encapsulate HEWL(Lip_HEWL_DDAB)for oral delivery.Lip_HEWL_DDAB was spherical with an average diameter of 162.7±1.6 nm and zeta potential of 37.1±4.3 mV.The Lip_HEWL_DDAB had high entrapment efficiency of 80%and 11%loading efficiency of HEWL.The formulated Lip_HEWL_DDAB were highly physicochemical stable in both simulated gastric fluid(SGF)and simulated intestinal fluid(SIF)and capable of enhancing the intestinal absorption via their mucoadhesive property while retaining antimicrobial activity against enteric bacteria.HEWL was released from Lip_HEWL_DDAB via diffusion mechanism at higher extent than those without the DDAB.Additionally,the prepared Lip_HEWL_DDAB was non-toxic at below 6.25μg/ml to intestinal cells and was able to deliver HEWL across an in vitro intestinal epithelium model,resulting in enhanced anti-microbial/anti-inflammatory activities,compared to their free-and unmodified-liposomal forms.Together,our modified cationic liposome is a new and promising strategy for improving oral delivery of HEWL with enhanced nutraceutical functions.展开更多
文摘The vesicle of didodecyldimethylammonium bromide (DDAB) which containedtetrathiafulvalene (TTF) was mixed with xanthine oxidase, and the mixture was cast on the pyrolyticgraphite electrode. The lipid films were used to supply a biological environment resemblingbiomembrane on the surface of the electrode. TTF was used as a mediator because of its highelectron-transfer efficiency. A novel xanthine biosensor based on cast DDAB film was developed. Theeffects of pH and operating potential were explored for optimum analytical performance by using theamperometric method. The response time of the biosensor was less than 10 s. The detection limit ofthe biosensor was 3.2 x 10^(-7) mol/L and the liner range was from 4 x 10^(-7) mol/L to 2.4 x10^(-6) mol/L.
基金supported by National Science and Technology Development Agency(NSTDA),Thailand[Project No.P-2051071,2021].
文摘Hen egg white lysozyme(HEWL)is a food-derived antimicrobial protein,exhibiting bacteriolytic activity against several bacteria including foodborne enteric pathogens.It has been approved for using in food,pharmacological and therapeutic applications.However,using HEWL through the ingestion is still a challenge due to its poor stability and low bioavailability in the gastro-intestinal tract(GIT).Herein,liposomes incorporating with dimethyl dioctadecyl ammonium bromide(DDAB)were fabricated to encapsulate HEWL(Lip_HEWL_DDAB)for oral delivery.Lip_HEWL_DDAB was spherical with an average diameter of 162.7±1.6 nm and zeta potential of 37.1±4.3 mV.The Lip_HEWL_DDAB had high entrapment efficiency of 80%and 11%loading efficiency of HEWL.The formulated Lip_HEWL_DDAB were highly physicochemical stable in both simulated gastric fluid(SGF)and simulated intestinal fluid(SIF)and capable of enhancing the intestinal absorption via their mucoadhesive property while retaining antimicrobial activity against enteric bacteria.HEWL was released from Lip_HEWL_DDAB via diffusion mechanism at higher extent than those without the DDAB.Additionally,the prepared Lip_HEWL_DDAB was non-toxic at below 6.25μg/ml to intestinal cells and was able to deliver HEWL across an in vitro intestinal epithelium model,resulting in enhanced anti-microbial/anti-inflammatory activities,compared to their free-and unmodified-liposomal forms.Together,our modified cationic liposome is a new and promising strategy for improving oral delivery of HEWL with enhanced nutraceutical functions.
