Disintegratable core/shell silica particles for encapsulating and releasing bioactive macromolecules

The present invention relates to disintegratable core/shell silica particles encapsulating a bioactive macromolecule or bioactive macromolecule cluster in an active conformation, a method for producing the same, and uses thereof

Pengembangan Molecular Imprinted Polymer Untuk Pemisahan Vitamin C dalam Sediaan Multivitamin

Vitamin C has chromophore group that can be analyzed using UV-Vis spectrophotometry, however if the complex matrix to be analyzed like multivitamins, a selective separation method is required to eliminate matrix interferences. One of the selective separation methods is Molecular Imprinted Polymer (MIP) which which hasn’t been widely used in multivitamin samples. The purpose of this study was to obtain selective MIP for separation of vitamin C in multivitamins.. Research methods included interaction observation of vitamin C with functional monomers using UV spectrophotometry, MIP was synthesized using bulk method for 24 hours at 60 °C. MIP was characterized using spectrophotometry, infrared and scanning electron microscopy MIP selectivity were determined by determination of imprinting factor and its recovery with the liquid-liquid extraction method (LLE) and SPE C18 for separation of vitamin C in multivitamin samples on the market using a validated method. Hypsochromic shift showed interaction between vitamin C and functional monomers, which hydrogen bonds were taking role in MIP synthesis. Imprinting factor more than 1 and recovery value close to 100% indicated MIP selectivity to vitamin C. MIP-1 had the highest selectivity compared to the ECC and SPE C18 methods for separation of vitamin C in multivitamin samples with recovery of 98.17 ± 2.31%, 69.42 ± 3.01%, and 93.26±4.24% respectively. Synthesized MIP-1 was selective for the separation of vitamin C in multivitamins. Vitamin C memiliki gugus kromofor dan dapat dianalisis menggunakan spektrofotometri UV, namun apabila matriks yang akan dianalisis berupa multivitamin yang kompleks diperlukan metode pemisahan yang selektif untuk mengurangi interferensi dari matriks. Salah satu metode pemisahan yang selektif dalam pemisahan adalah Molecular Imprinted Polymer (MIP) yang belum banyak digunakan dalam sampel multivitamin. Penelitian ini bertujuan untuk memperoleh MIP yang selektif untuk pemisahan vitamin C dalam sediaan multivitamin. Metode penelitian meliputi pengamatan interaksi vitamin C dengan monomer fungsional menggunakan spektrofotomeri UV. MIP disintesis dengan menggunakan metode ruah selama 24 jam pada suhu 60 °C. MIP dikarakterisasi menggunakan menggunakan spektrofotometri inframerah dan scanning electron microscopy. Selektivitas MIP ditentukan dengan pengujian faktor imprinting dan perbandingan perolehan kembalinya terhadap metode ekstraksi cair-cair (ECC) dan SPE C18 untuk pemisahan vitamin C dalam sampel multivitamin di pasaran menggunakan metode yang telah tervalidasi.   Pergeseran hipsokromik menunjukkan adanya interaksi antara vitamin C dengan monomer fungsional di mana ikatan hidrogen berperan dominan dalam sintesis MIP. Faktor imprinting yang lebih dari 1 dan nilai perolehan kembali yang mendekati 100% menunjukkan selektivitas MIP terhadap vitamin C. MIP-1 memiliki selektivitas paling tinggi dibandingkan dengan metode ECC dan SPE C18 untuk pemisahan vitamin C dalam sampel multivitamin dengan persen perolehan kembali berturut-turut sebesar 98,17±2,31%, 69,42±3,01%, dan 93,26±4,24%. MIP-1 yang dihasilkan selektif untuk pemisahan vitamin C dalam sediaan multivitamin. &nbsp

Fast targeting and cancer cell uptake of luminescent antibody-nanozeolite bioconjugates

Understanding the targeted cellular uptake of nanomaterials is an essential step to engineer and program functional and effective biomedical devices. In this respect, the targeting and ultrafast uptake of zeolite nanocrystals functionalized with Cetuximab antibodies (Ctxb) by cells overexpressing the epidermal growth factor receptor are described here. Biochemical assays show that the cellular uptake of the bioconjugate in the targeted cancer cells already begins 15 min after incubation, at a rate around tenfold faster than that observed in the negative control cells. These findings further show the role of Ctxb exposed at the surfaces of the zeolite nanocrystals in mediating the targeted and rapid cellular uptake. By using temperature and pharmacological inhibitors as modulators of the internalization pathways, the results univocally suggest a dissipative uptake mechanism of these nanomaterials, which seems to occur using different internalization pathways, according to the targeting properties of these nanocrystals. Owing to the ultrafast uptake process, harmless for the cell viability, these results further pave the way for the design of novel theranostic tools based on nanozeolite

The Role of a Confined Space on the Reactivity and Emission Properties of Copper(I) Clusters

Metal clusters have gained a lot of interest for their remarkable photoluminescence and catalytic properties. However, a major drawback of such materials is their poor stability in air and humidity conditions. Herein we describe a versatile method to synthesize luminescent Cu(I) clusters inside the pores of zeolites, using a sublimation technique with the help of high vacuum and high temperature. The porous materials play an essential role as a protecting media against the undesirable and easy oxidation of Cu(I). The obtained clusters show fascinating luminescence properties, and their reactivity can be triggered by insertion in the pores of organic monodentate ligands such as pyridine or triphenylphosphine. The coordinating ligands can lead to the formation of Cu(I) complexes with completely different emission properties. In the case of pyridine, the final compound was characterized and identified as a cubane-like structure. A thermochromism effect is also observed, featuring, for instance, a hypsochromic effect for a phosphine derivative at 77K. The stability of the encapsulated systems in zeolites is rather enthralling: they are stable and emissive even after several months in the air

EFEKTIVITAS ENKAPSULASI ENZIM PROTEASE DENGAN BEAD HIDROGEL BERBAHAN ALGINAT-KITOSAN

Introduction: The addition of the protease enzyme from an external source can increase protein absorption in the human digestive system. Protease enzyme is formulated by encapsulated inside alginate-chitosan hydrogel beads to deny immediate proteolysis reaction with the protein consumed and maintain the encapsulated enzyme in a temperature range acidity. This research aims to know the encapsulation effectivity of protease enzyme with alginate-chitosan hydrogel beads. Methods: Experiments were conducted to encapsulate protease enzyme with ionotropic gelation method using alginate and chitosan. Encapsulation yield, bead size, encapsulated enzyme activity, release rate, and stability were analyzed from the hydrogel beads that were obtained. The data is then analyzed using analysis of variance (ANOVA) and Duncan’s Multiple Range Test (DMRT). Results: From four variants of hydrogel beads that were obtained, this research shows that the volume addition of alginate solution in the encapsulation material will increase the value of encapsulation yield (EY), bead size, and release rate of the encapsulated protease enzyme. Therefore, the volume addition of chitosan solution will increase the value of encapsulation efficiency (EE). Hydrogel beads incubation at 6°C for 24 days maintain 75,55% of encapsulated enzyme activity. Conclusion: Protease enzyme can be formulated with protein by being encapsulated with alginate-chitosan hydrogel beads. Key Words: alginate, chitosan, protease enzyme encapsulationPendahuluan: Penambahan enzim protease dari sumber lain dapat meningkatkan penyerapan protein oleh organ pencernaan manusia. Enzim protease dari sumber lain diformulasikan dengan cara dienkapsulasi dalam bead hidrogel agar tidak langsung bereaksi dengan protein yang dikonsumsi dan tahan terhadap lingkungan suhu dan keasaman. Penelitian ini bertujuan untuk mengetahui efektivitas enkapsulasi enzim protease dengan bead hidrogel berbahan alginat-kitosan. Metode: Penelitian ini dilakukan secara eksperimental untuk mengenkapsulasi enzim protease dengan metode ionotropic gelationdengan bahan alginat dan kitosan. Bead hidrogel yang terbentuk akan dianalisis yield enkapsulasi, ukuran bead yang terbentuk, aktivitas, tingkat pelepasan, dan stabilitas enzim protease yang dienkapsulasi. Data kemudian akan dianalisis variasinya dengan menggunakan uji analisis keragaman (ANOVA) dan uji beda nyata terkecil Duncan’s Multiple Range Test (DMRT). Hasil: Hasil dari penelitian ini menunjukkan bahwa dari keempat variasi bead hidrogel yang terbentuk, penambahan volume larutan alginat pada bahan enkapsulasi akan meningkatkan nilai yield enkapsulasi (EY), ukuran bead, dan tingkat pelepasan enzim yang dienkapsulasi (L), sementara penambahan volume larutan kitosan akan meningkatkan nilai efisiensi enkapsulasi (EE). Inkubasi bead selama 24 hari pada suhu 6°C berhasil mempertahankan aktivitas enzim protease yang dienkapsulasi sebesar 75,55%. Simpulan: Enzim protease dapat diformulasikan dengan dienkapsulasi dalam bead hidrogel berbahan alginat-kitosan. Kata Kunci: alginat, enkapsulasi enzim protease, kitosa

Enhanced Activity of TiO2/Natural Zeolite Composite for Degradation of Methyl Orange under Visible Light Irradiation

A series of titanium dioxide nanoparticles anchored on mordenite zeolite from an Indonesian natural deposit were prepared by the sol-gel route using a titanium isopropoxide sol as the precursor. Mordenite was incorporated during the sol-gel process by dispersing mordenite powder into the titania sol-gel precursor. The resulting titanium dioxide nanoparticles were in the anatase and rutile form, as confirmed by X-Ray diffraction (XRD) spectroscopy. Diffuse reflectance ultra violet visible (DR-UVVis) spectroscopy analysis indicated a red shift for the band gap energy, which enabled the materials to absorb ultraviolet to visible light. Subjecting the material to photodegradation in a reactor under ultraviolet and visible radiation gave better dye degradation under visible light than ultraviolet irradiation and the yield was proportional with the content of TiO2 nanoparticles incorporated into the zeolite

Inside Cover: Breakable Hybrid Organosilica Nanocapsules for Protein Delivery (Angew. Chem. Int. Ed. 10/2016)

The direct delivery of specific proteins to live cells promises a tremendous impact for biological and medical applications, from therapeutics to genetic engineering. However, the process mostly involves tedious techniques and often requires extensive alteration of the protein itself. Herein we report a straightforward approach to encapsulate native proteins by using breakable organosilica matrices that disintegrate upon exposure to a chemical stimulus. The biomolecule-containing capsules were tested for the intracellular delivery of highly cytotoxic proteins into C6 glioma cells. We demonstrate that the shell is broken, the release of the active proteins occurs, and therefore our hybrid architecture is a promising strategy to deliver fragile biomacromolecules into living organisms

Breakable Hybrid Organosilica Nanocapsules for Protein Delivery

The direct delivery of specific proteins to live cells promises a tremendous impact for biological and medical applications, from therapeutics to genetic engineering. However, the process mostly involves tedious techniques and often requires extensive alteration of the protein itself. Herein we report a straightforward approach to encapsulate native proteins by using breakable organosilica matrices that disintegrate upon exposure to a chemical stimulus. The biomolecule-containing capsules were tested for the intracellular delivery of highly cytotoxic proteins into C6 glioma cells. We demonstrate that the shell is broken, the release of the active proteins occurs, and therefore our hybrid architecture is a promising strategy to deliver fragile biomacromolecules into living organisms

Modular Graphene-Based 3D Covalent Networks: Functional Architectures for Energy Applications

International audienceThe development of ordered graphene-based materials combining high stability, large surface areas, ability to act as absorbent of relevant chemical species, and solution processability is of significance for energy applications. A poorly explored approach relies on the controlled nanostructuration of graphene into robust and highly ordered 3D networks as a route to further leverage the exceptional properties of this unique material. Here, a simple yet effective and scalable one-step method is reported to prepare graphene-based 3D covalent networks (G3DCNs) with tunable interlayer distance via controlled polymerization of benzidines with graphene oxide at different reaction temperatures under catalyst- and template-free conditions. The reduced form of G3DCNs is used as electrodes in supercapacitors; it reveals a high specific capacitance of 156 F g−1 at a current density of 1 A g−1 in a two-electrode configuration and 460 F g−1 at a current density of 0.5 A g−1 in a three-electrode configuration, combined with an excellent cycling stability over 5000 cycles. The present study will promote the quantitative understanding of structure–property relationship, for the controlled fabrication of 3D graphene-based multifunctional materials

Combined Delivery of Temozolomide and Anti-miR221 PNA Using Mesoporous Silica Nanoparticles Induces Apoptosis in Resistant Glioma Cells

Mesoporous silica nanoparticles (MSNPs), 100 nm in size, incorporating a Cy5 fluorophore within the silica framework, are synthesized and loaded with the anti-cancer drug temozolomide (TMZ), used in the treatment of gliomas. The surface of the particles is then decorated, using electrostatic interactions, with a polyarginine-peptide nucleic acid (R8-PNA) conjugate targeting the miR221 microRNA. The multi-functional nanosystem thus obtained is rapidly internalized into glioma C6 or T98G cells. The anti-miR activity of the PNA is retained, as confirmed by reverse transcription polymerase chain reaction (RT-PCR) measurements and induction of apoptosis is observed in temozolomide-resistant cell lines. The TMZ-loaded MSNPs show an enhanced pro-apoptotic effect, and the combined effect of TMZ and R8-PNA in the MSNPs shows the most effective induction of apoptosis (70.9% of apoptotic cells) thus far achieved in the temozolomide-resistant T98G cell line