The properties as biointerfaces of electroactive conducting polymer-peptide biocomposites formed by poly(3,4-ethylenedioxythiophene) (PEDOT) and CREKA or CR(NMe)EKA peptide sequences (where Glu has been replaced by N-methyl-Glu in the latter) have been compared. CREKA is a linear pentapeptide that recognizes clotted plasma proteins and selectively homes to tumors, while CR(NMe)EKA is an engineer to improve such properties by altering peptide-fibrin interactions. Differences between PEDOT-CREKA and PEDOT-CR(NMe)EKA reflect dissemblance in the organization of the peptides into the polymeric matrix. Both peptides affect fibrinogen thrombin-catalyzed polymerization causing the immediate formation of fibrin, whereas in the absence of thrombin this phenomenon is only observed for CR(NMe)EKA. Consistently, the fibrin-adsorption capacity is higher for PEDOT-CR(NMe)EKA than for PEDOT-CREKA, even though in both cases adsorbed fibrin exhibits round-like morphologies rather than the characteristic fibrous structure. PEDOT-peptide films coated with fibrin are selective in terms of cell adhesion, promoting the attachment of metastatic cells with respect to normal cells.
Lanz, A.; Martinez de Ilarduya, A.; Portilla, J.A.; Garcia, M.; Holler, E.; Ljubimova, J.; Muñoz, S. Macromolecular bioscience Vol. 14, num. 9, p. 1325-1336 DOI: 10.1002/mabi.201400124 Data de publicació: 2014-09-01 Article en revista
Esterification of microbial poly(malic acid) is performed with either ethanol or 1-butanol to obtain polymalate conjugates capable to form nanoparticles (100–350 nm). Degradation under physiological conditions takes place with release of malic acid and the corresponding alcohol as unique degradation products. The anticancer drugs Temozolomide and Doxorubicin are encapsulated in nanoparticles with efficiency of 17 and 37%, respectively. In vitro drug release assays show that Temozolomide is almost completely discharged in a few hours whereas Doxorubicin is steadily released along several days. Drug-loaded nano-particles show remarkable effectiveness against cancer cells. Partially ethylated poly(malic acid) nano-particles are those showing the highest cellular uptake.
PLA MPs are prepared via a novel and toxic-chemical-free fabrication route using ethyl lactate,
a green solvent and FDA-approved aroma. MPs are obtained by a solution jet break-up and
solvent displacement method. Adjusting flow parameters allows the tuning of MPs size
between 60 and 180 mm, with reduced polydispersity.
Morphological analysis shows microporous particles
with Janus-like surface. A fluorophore is successfully
loaded into the MPs during their formation step. This
versatile green solvent-based procedure is proven to be
suitable for drug encapsulation and delivery applications.
The method may be extended to different
droplet generation techniques.
Lanz, A.; Garcia, M.; Portilla, J.A.; Martinez de Ilarduya, A.; Patil, R.; Holler, E.; Ljubimova, J.; Muñoz, S. Macromolecular bioscience Vol. 11, num. 10, p. 1370-1377 DOI: 10.1002/mabi.201100107 Data de publicació: 2011-10-10 Article en revista
PMLA nanoparticles with diameters of 150–250nm are prepared, and their hydrolytic degradation
is studied under physiological conditions. Degradation occurs by hydrolysis of the side
chain methyl ester followed by cleavage of the main-chain ester group with methanol and
L-malic acid as the final degradation products. No
alteration of the cell viability is found after 1 h of
incubation, but toxicity increases significantly after
3 d, probably due to the noxious effect of the released
methanol. Anticancer drugs temozolomide and doxorubicin
are encapsulated in the NPs with 20–40% efficiency,
and their release is monitored using in vitro
essays. Temozolomide is fully liberated within several
hours, whereas doxorubicin is steadily released from
the particles over a period of 1 month.
This work reports a comprehensive study about cell adhesion and proliferation on the surface of different electroactive substrates formed by p-conjugated polymers. Biological assays were performed considering four different cellular lines: two epithelial and two fibroblasts. On the other hand, the electroactivity of the three conducting systems was determined in physiological conditions. Results indicate that the three substrates behave as a cellular matrix, even though compatibility with cells is larger for PPy and the 3-layered system. Furthermore, the three polymeric systems are electro-compatible with the cellular monolayers.