sonita siboro - Academia.edu (original) (raw)

Papers by sonita siboro

Journal of Korean Society for Imaging Science, Dec 31, 2019

Natural naphthoquinones such as lapachol (Lp) have demonstrated promising biological activities. ... more Natural naphthoquinones such as lapachol (Lp) have demonstrated promising biological activities. However, these quinones present low systemic biodisponibility due to its poor aqueous solubility. To overcome this problem, nanoemulsions (NE) formed by oily core are able to incorporate hydrophobic molecules thus enabling them to be dispersed into an aqueous phase. The present study reports the development, characterization, and physical stability of NE containing lapachol. NE formulations (F1, F2, F3, F4, and F2-Lp) were prepared using emulsion phase inversion (EPI) method and characterized in relation to droplet size, size distribution (PDI), zeta potential, and physical stability. The formulation chosen to incorporate lapachol (F2-Lp) showed droplet size in nanometric scale with homogeneous size distribution (PDI < 0.2) and negative zeta potential (about −30 mV). In addition, good physical stability of F2 and F2-Lp was demonstrated using analytical centrifugation with photometric detection where the light transmission profiles did not change throughout the dispersions. Nanoemulsion containing lapachol presented a strong reddish aspect; however, the incorporation of this naphthoquinone did not alter the main physicochemical parameters of NE formulation. The in vitro release study demonstrated a sustained release profile from NE with about 60% of lapachol released within 54 h.

$Research paper thumbnail of 2P-6 : Formation of stable micellar nanoemulsion oil-in-water for delivery of natural cosmetic meroterpenoid-rich fraction from the ethanolic extract of Sargassum macrocarpum$

In this study, nano-emulsion structures were employed in order to improve the storage stability a... more In this study, nano-emulsion structures were employed in order to improve the storage stability and dermal permeability of naturally derived seaweed extracts (the scientific name Sargassum serratifolium, MES) with excellent whitening and crease improvement, and the optimal preparation condition for the nano-emulsions were investigated. The MES, obtained using the concentration, decontamination, and desalination process of the extracts, consists of active ingredients of hydrophobic property and is not suitable for cosmetic materials due to easy oxidation. In this study, O/W nano-emulsions encapsulating MES were prepared using various surfactants and additives such as polyoxyl caster oil EL, Poloxamer 407, and PEG 400. The combined sequence of components used in the process and the effect of the chemical composition ratio were studied systematically. The average size of nano-emulsions prepared under optimized conditions was in the range 20 ~30 nm, and the performance of the melanin sy...

Carbohydrate Polymers, 2021

Task-specific drug release is essential in the development of hydrogels as drug delivery systems.... more Task-specific drug release is essential in the development of hydrogels as drug delivery systems. The aim of the study is to report the effect of porosity on alginate hydrogels, which may be controlled by the design of crosslinkers, on drug release behavior. Two alginate-based hydrogels were prepared: alginate-norbornene (Alg-Nb) crosslinked by disulfide-tetrazine (S-Tz; hydrogel A) and alginate-furfuryl amine (Alg-FA) crosslinked by disulfide-maleimide (S-Ma; hydrogel B). Results showed the porosity of hydrogel A was controllable by adjusting the amount of S-Tz. Gel formation was facilitated by a "click" reaction between Alg-Nb and S-Tz, producing nitrogen gas, which, in turn, acted as an in-situ pore generator. Hydrogel B showed a non-porous morphology, as gelation was processed via addition reaction between Alg-FA and S-Ma, which produced no by-product. The study showed that crosslinker proportion and porosity were significant factors influencing drug release behavior of the alginate hydrogels. The presence of a porous structure increased the drug release while non-porous hydrogels led to a very slow release. In addition, the porous alginate hydrogels could sustainably release doxorubicin for 35 days.

Molecular Crystals and Liquid Crystals, 2020

In this study, gold nanoparticles (GNPs) were successfully fabricated via a polymer-templating me... more In this study, gold nanoparticles (GNPs) were successfully fabricated via a polymer-templating method and applied for surface-enhanced Raman scattering (SERS) enhancement. The block copolymer, poly(ethylene glycol)-block-poly(styrene-alt-maleic anhydride) (PEG-b-PSM) modified with thiol groups, was used to prepare GNPs. The results indicated that the polymer facilitated GNPs to form an assembly without aggregation; thus, the distance between adjacent GNPs could be ideal for SERS application. Furthermore, when deposited onto indium tin oxide (ITO) thin film, GNPs prepared via the polymer-templating method showed more ordered behavior than GNPs prepared by using a conventional method, that is, citrate reduction.

Materials, 2020

In this article, a drug delivery system with a near-infrared (NIR) light-responsive feature was s... more In this article, a drug delivery system with a near-infrared (NIR) light-responsive feature was successfully prepared using a block copolymer poly(ethylene oxide)-b-poly(glycidyl methacrylate)-azide (PEO-b-PGMA-N3) and a cross-linker containing a Se-Se bond through “click” chemistry. Doxorubicin (DOX) was loaded into the core-cross-linked (CCL) micelles of the block copolymer along with indocyanine green (ICG) as a generator of reactive oxygen species (ROS). During NIR light exposure, ROS were generated by ICG and attacked the Se-Se bond of the cross-linker, leading to de-crosslinking of the CCL micelles. After NIR irradiation, the CCL micelles were continuously disrupted, which can be a good indication for effective drug release. Photothermal analysis showed that the temperature elevation during NIR exposure was negligible, thus safe for normal cells. In vitro drug release tests demonstrated that the drug release from diselenide CCL micelles could be controlled by NIR irradiation a...

Reactive and Functional Polymers, 2020

, et al., Ultrasoundaccelerated covalent-functionalization of reduced graphene oxide with imidazo... more , et al., Ultrasoundaccelerated covalent-functionalization of reduced graphene oxide with imidazolium-based poly(ionic liquid)s by Diels-Alder click reaction for supercapacitors, Reactive and Functional Polymers (2020),

Polymer Degradation and Stability, 2019

The use of diselenide core cross-linked polymeric micelles assisted with indocyanine green (ICG) ... more The use of diselenide core cross-linked polymeric micelles assisted with indocyanine green (ICG) as a near-infrared (NIR)-responsive drug delivery system was known to be promising in terms of wellcontrolled release as well as biocompatibility. However, we must note that the effect of NIR exposure is not simply promoting cleavage of SeeSe bonds. In this work, we report a systematic investigation to the effect of NIR light exposure on the polymeric micelles of poly(ethylene glycol)-block-poly(styrene-altmaleic anhydride) loaded with ICG. Diselenide core-cross-linked micelles and non-cross-linked micelles were prepared for the investigation. The results showed that the reactive oxygen species (ROS) produced from ICG not only reacted with diselenide bonds but also attacked poly(ethylene glycol) chains, resulting in the polymer degradation. The polymer degradation appeared to be continuous even for 36 h after NIR exposure was stopped, as evidenced in DLS, GPC, and TEM measurements. This study provides insight into essential parameters which should be considered in designing ROS-responsive drug delivery systems based on polymeric micelles.

Polymer, 2021