Evaluation of a combined drug-delivery system for proteins assembled with polymeric nanoparticles and porous microspheres; characterization and protein integrity studies.
This work presents an evaluation of the adsorption/infiltration process in relation to the loading of a model protein, α-amylase, into an assembled biodegradable polymeric system, free of organic solvents and made up of poly(D,L-lactide-co-glycolide) acid (PLGA). Systems were assembled in a friendly aqueous medium by adsorbing and infiltrating polymeric nanoparticles into porous microspheres. These assembled systems are able to load therapeutic amounts of the drug through adsorption of the protein onto the large surface area characteristic of polymeric nanoparticles. The subsequent infiltration of nanoparticles adsorbed with the protein into porous microspheres enabled the controlled release of the protein as a function of the amount of infiltrated nanoparticles, since the surface area available on the porous structure is saturated at different levels, thus modifying the protein release rate. Findings were confirmed by both the BET technique (N2 isotherms) and in vitro release studies. During the adsorption process, the pH of the medium plays an important role by creating an environment that favors adsorption between the surfaces of the micro- and nano-structures and the protein. Finally, assays of α-amylase activity using 2-chloro-4-nitrophenyl-α-D-maltotrioside (CNP-G3) as the substrate and the circular dichroism technique confirmed that when this new approach was used no conformational changes were observed in the protein after release.
Laboratorio de Investigación y Posgrado en Tecnología Farmacéutica, Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México, Avenida 1° de Mayo s/n, Campo 1, Cuautitlán Izcalli, Estado de México CP 54743, Mexico.
Sergio
S
Alcalá-Alcalá
Laboratorio de Investigación Bioquímica, Sección de Estudios de Posgrado e Investigación, ENMyH-Instituto Politécnico Nacional, Guillermo Massieu Helguera No. 239, La Escalera Ticomán, 07320 D.F., Mexico.
Claudia G
CG
Benítez-Cardoza
Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Circuito exterior s/n, Cd. Universitaria, Del. Coyoacán, CP 04510 D.F., Mexico.
Enrique J
EJ
Lima-Muñoz
Laboratorio de Investigación y Posgrado en Tecnología Farmacéutica, Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México, Avenida 1° de Mayo s/n, Campo 1, Cuautitlán Izcalli, Estado de México CP 54743, Mexico.
Elizabeth
E
Piñón-Segundo
Laboratorio de Investigación y Posgrado en Tecnología Farmacéutica, Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México, Avenida 1° de Mayo s/n, Campo 1, Cuautitlán Izcalli, Estado de México CP 54743, Mexico. Electronic address: quintana@servidor.unam.mx.
David
D
Quintanar-Guerrero
D000327:Adsorption; D002942:Circular Dichroism; D016503:Drug Delivery Systems; D019344:Lactic Acid / Q000737:chemistry*; D008863:Microspheres; D053758:Nanoparticles / Q000737:chemistry*; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D016062:Porosity; D014312:Trisaccharides / Q000737:chemistry; D000516:alpha-Amylases / Q000737:chemistry*
D014312:Trisaccharides; C057413:2-chloro-4-nitrophenylmaltotrioside; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D000516:alpha-Amylases
2-Chloro-4-nitrophenyl-α-d-maltotrioside (PubChem CID: 9939545); Adsorption/infiltration; Poly(d,l-lactide-co-glycolide) acid (PubChem CID: 23111554); Polymeric nanoparticles; Porous microspheres; Protein delivery; Protein formulation