Study on preparation and regulation of cationic polylactic acid nano⁃microparticles for vaccine adjuvant

doi:10.19491/j.issn.1001-9278.2025.07.002

Abstract

Abstract:

DDAB⁃PLA nano⁃microparticles were synthesized via an improved emulsification method， with particle size controlled by adjusting the oil/water phase ratio and emulsifier concentration. The cytotoxicity of DDAB⁃PLA particles with varying cationic contents was also evaluated. The resulting particles exhibited a nano⁃ to micro⁃scale size distribution， with an average diameter of approximately 490 nm. By modulating the aqueous phase volume and emulsifier concentration， the particle size could be precisely tuned within the range of 169~786 nm. Furthermore， DDAB⁃PLA nano⁃microparticles demonstrated negligible cytotoxicity toward L929 cells and DC， indicating excellent biocompatibility.

Key words: polylactic acid, emulsification method, nano?microparticle, particle size, vaccine adjuvant

CLC Number:

TQ321

ZHAO Xiaohuan, WANG Yansen, SUN Jingshan, DENG Jingqian, QI Liya, HOU Dandan, WANG Chunyao, TAN Xinyu. Study on preparation and regulation of cationic polylactic acid nano⁃microparticles for vaccine adjuvant[J]. China Plastics, 2025, 39(7): 6-11.

Figures/Tables 11

Fig.1. Morphology and size distribution of cationic PLA nano⁃microparticles

Fig.2. XPS spectra and Zeta potential of PLA nano⁃microparticles before and after cationic modification

样品名称	初次水相体积/mL	二次水相体积/mL	粒径/nm
DDAB⁃PLA⁃1	50	0	490±136
DDAB⁃PLA⁃2	40	10	528±232
DDAB⁃PLA⁃3	30	20	552±241
DDAB⁃PLA⁃4	20	30	618±262
DDAB⁃PLA⁃5	10	40	786±327

Tab.1. Parameters and Numbers of DDAB⁃PLA by changing the volume of water phase

Fig.3. SEM of DDAB⁃PLA nano⁃microparticles prepared by altering the volume of water phase

Fig.4. Size distribution of DDAB⁃PLA nano⁃microparticles prepared by altering the volume of water phase

样品名称	初次水相体积/mL	PVA水相浓度/%	粒径/ nm
DDAB⁃PLA⁃6	50	0	192±38
DDAB⁃PLA⁃7	50	1	167±20
DDAB⁃PLA⁃8	50	2	368±92
DDAB⁃PLA⁃1	50	4	490±136
DDAB⁃PLA⁃9	50	6	579±119

Tab.2. Parameters and numbers of DDAB⁃PLA by changing the volume of water phase

Fig.5. DDAB⁃PLA nano⁃microparticles prepared by altering the content of emulsifier

Fig.6. Size distribution of DDAB⁃PLA nano⁃microparticles prepared by altering the content of emulsifier

样品名称	初次水相体积/mL	PVA水相浓度/%	m_DDAB∶m_PLA
PLA	50	4	0
DDAB1⁃PLA	50	4	10∶1
DDAB2⁃PLA	50	4	5∶1
DDAB3⁃PLA	50	4	2∶1
DDAB4⁃PLA	50	4	1∶1

Tab.3. Parameters and numbers of PLA with different cation contents

Fig.7. Effect of the DDAB⁃PLA prepared with different cation contents on the vitality of L929 cells

Fig.8. Effect of the DDAB⁃PLA prepared with different cation contents on the vitality of L929 cells

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