THE COLLOIDAL PROPERTIES OF SURFACTANT-FREE BIODEGRADABLE NANOSPHERES FROM POLY(

2020-03-26 16:10:36

The poly acid stabilization PMLABe

责任者: STOLNIK, S;GARNETT, MC;DAVIES, MC;ILLUM, L;BOUSTA, M;VERT, M;DAVIS, SS 单位: UNIV MONTPELLIER 1, CTR RECH BIOPOLYMERES ARTIFICIELS, F-34060 MONTPELLIER, FRANCE. 来源出处: COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS, v 97, APR 28 1995, p 235- 245 摘要: The colloidal properties of surfactant-free nanospheres prepared from biodegradable polyesters, i.e. a range of benzyl esters of poly(beta-malic acid) (PMLABeH) and poly(lactic acid-co-glycolide) (PLGA) have been investigated. The results reveal a significant difference in the colloidal behaviour of the nanosphere systems, depending on the composition of the copolymer used in their preparation. The nanospheres from the PLGA and fully benzylated PMLABe(100) polymer were relatively less stable to addition of electrolyte and coagulated around the pH which coincided with the dissociation constant of the carboxyl group, The coagulation was associated with a decrease in the zeta potential below a certain critical value needed for electrostatical stabilization. In comparison: nanospheres prepared from partly benzylated PMLABe(80)H(20) and PMLABe(90)H(10) copolymers did not coagulate at relatively high electrolyte concentrations and at low pH values of the suspending buffer. This may be interpreted in terms of an involvement of a steric component to nanosphere stabilization, whereby the steric component appears to be associated with the presence of an increased level of carboxyl groups on the nanosphere surface. The results suggest a different construction of nanospheres prepared from partly benzylated copolymers from those prepared from fully benzylated PMLABe(100) and PLGA copolymers. 关键词: BENZYL ESTERS OF POLY(BETA-MALIC ACID); BIODEGRADABLE COLLOID; COLLOIDAL STABILITY; DRUG CARRIERS; ELECTROSTATIC STABILIZATION; COLLOIDAL STABILITY; DRUG CARRIERS; ELECTROSTATIC STABILIZATION; POLY(LACTIC ACID-CO-GLYCOLIDE); STERIC STABILIZATION; ZETA POTENTIAL PH POLY(LACTIC ACID-CO-GLYCOLIDE); STERIC STABILIZATION; ZETA POTENTIAL PH PROFILES PROFILES; LATEX; STABILIZATION; MICROSPHERES; COPOLYMERS; PARTICLES; POLYMER; CELLS CELLS