Nanoparticles Prepared From Pterostilbene (PTE): A New Strategy for Reducing Blood Glucose and Improving Diabetic Complications

Aim: New envisions are put forward on the cross application of plant extracts and biomaterials, especially new conjectures are put forward on glucose lowering nanodrug delivery systems.Study design and methods: In this study, pterostilbene (PTE) was esterified with acryloyl chloride firstly, and then 3-acrylamidophenyl boric acid (AAPBA) and PTE esterified by acryloyl chloride were copolymerized into p(AAPBA-b-PTE). The characterization and structure of its polymer were examined. Additionally, p(AAPBA-b-PTE) nanoparticles and insulin loaded p(AAPBA-b-PTE) nanoparticles were prepared. The properties of pH, temperature and glucose sensitivity were investigated. And tested the drug loading and release of NPs. The nanoparticle toxicity was observed through cell and animal experiments, and the nanoparticle biodegradation process under physiological conditions was also observed. Finally, the effects of NPs on reducing blood sugar, antioxidation and improving micro inflammation were investigated in vivo.Results: Based on PTE, we successfully synthesized p(AAPBA-b-PTE) NPs. The NPs were basically round in shape with sizes between 150 and 250 nm. It has good pH and glucose sensitivity. The entrapment efficiency (EE) of insulin loaded NPs is about 56%, and the drug loading (LC) is about 13%. The highest release of insulin was 70%, and the highest release of PTE was 85%. Meanwhile, the insulin could undergo self-regulation according to the change of glucose concentration, thus achieving an effective and sustained release. Both in vivo and in vitro experiments showed that the NPs were safe and nontoxic. Under physiological conditions, it can be completely degraded within 40 days. Fourteen days after the mice were injected with p(AAPBA-b-PTE) NPs, there were no obvious abnormalities in the heart, liver, spleen, lung, and kidney. Moreover, the NPs can effectively reduce blood glucose, improve the antioxidant capacity and improve the micro inflammation status in mice.Conclusions: Using PTE as raw material, p(AAPBA-b-PTE) NPs were successfully prepared, which can effectively reduce blood glucose, improve antioxidant capacity, and reduce inflammatory response. It provided a new way for the combination of plant extracts and biomaterials to regulate and treat diseases through NPs or other dosage forms.

Tổng hợp polycaprolactone có nhóm tiol cuối mạch thông qua phản ứng tiol-michael

Functional polycaprolactones (PCL) have great potential for opening a new frontier in material design. We report here a method for preparing a thiol end-functionalized telechelic polycaprolactone using a straightforward and highly efficient process via the thiol-acrylate Micheal click addition reaction. Firstly, we esterified PCL diol with excess amount of acryloyl chloride resulting acrylate- end capped polycaprolactone (PCL-diacrylate). Then, thiol-end capped polycaprolactone (PCL-dithiol) was prepared by the reaction between 2,2′-(ethylenedioxy)diethanethiol and PCL-diacrylate in the present of base catalyst (Thiol-ene reaction). Both steps were carried out in the mild condition with high yield. The obtained product was structural analyzed using 1H NMR spectroscopy.

Synthesis of new Polyimides Derived from 4- minoantipyrine

In the present study, new five polymers of acryloyl chloride have been synthesized by reaction 4-aminoantipyrine with many substituted acid chloride (A-E). Then condensation of polyacryloyl chloride with the product in one step (A-E), in a suitable solvent in the presence amount of (Et3N) to obtain new polyimides(A1-E5). The prepared compounds were characterized by UV. FT-IR, 1H-NMR and 13C-NMR spectroscopy and measuring of other physical properties such as softening point, melting point and solublities.

Photocrosslinkable polymer based on 4-(3-(2,4-dichlorophenyl)-3-oxoprop-1-enyl) phenylacrylate: synthesis, reactivity ratio, and crosslinking studies

The acrylate monomer was synthesized by two step process. 2,4-dichloro-1-ene(4-hydroxyphenyl)phenone (DHP) was synthesized using 4-hydroxy benzaldehyde and 2,4-dichloro acetophenone. 4-[3-(2,4-dichloro-phenyl)3-oxoprop-1-en-1-yl]phenylacrylate (DCP) was prepared by reacting DHP with acryloyl chloride. The synthesized monomer was copolymerized with 2-hydroxyethyl acrylate and styrene using solution polymerization technique. Monomer and polymers were characterized by IR, NMR and UV techniques. The average molecular weight of the polymer was around 4000 g/mol. First and second decomposition temperature of the polymers was around 320 °C and 430 °C, respectively. The reactivity ratio of the polymers was calculated by Fineman-Ross, Kelen-Tudos and extended Kelen-Tudos methods. The synthesized monomer has been less reactive than the commercial monomer. The rate of photocrosslinking increased from 39 % to 99 % due to the using of copolymerization technique.