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1.
Molecules ; 29(5)2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38474660

RESUMO

In this study, novel amphiphilic polymer emulsifiers for avermectin (Avm) were synthesized facilely via the hydrolysis of ethylene-maleic anhydride copolymer (EMA) with different agents, and their structures were confirmed by various techniques. Then, water-based Avm-nanoemulsions were fabricated with the emulsifiers via phase inversion emulsification process, and superior emulsifier was selected via the emulsification effects. Using the superior emulsifier, an optimal Avm-nanoemulsion (defined as Avm@HEMA) with satisfying particle size of 156.8 ± 4.9 nm, encapsulation efficiency (EE) of 69.72 ± 4.01% and drug loading capacity (DLC) of 54.93 ± 1.12% was constructed based on response surface methodology (RSM). Owing to the emulsifier, the Avm@HEMA showed a series of advantages, including high stability, ultraviolet resistance, low surface tension, good spreading and high affinity to different leaves. Additionally, compared to pure Avm and Avm-emulsifiable concentrate (Avm-EC), Avm@HEMA displayed a controlled releasing feature. The encapsulated Avm was released quite slowly at normal conditions (pH 7.0, 25 °C or 15 °C) but could be released at an accelerated rate in weak acid (pH 5.5) or weak alkali (pH 8.5) media or at high temperature (40 °C). The drug releasing profiles of Avm@HEMA fit the Korsmeyer-Peppas model quite well at pH 7.0 and 25 °C (controlled by Fickian diffusion) and at pH 7.0 and 10 °C (controlled by non-Fickian diffusion), while it fits the logistic model under other conditions (pH 5.5 and 25 °C, pH 8.5 and 25 °C, pH 7.0 and 40 °C).

2.
Adv Mater ; 36(16): e2311717, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38230910

RESUMO

Solid-solid phase change materials (SSPCMs) with crosslinked polymer structures have received sustained interest due to their remarkable shape stability, enabling their application independently without the need for encapsulation or supporting materials. However, the crosslinking structure also compromises their latent heat and poses challenges to their recyclability. Herein, a novel strategy harnessing the internal-catalyzed reversible anhydride-alcohol crosslinking reaction to fabricate SSPCMs with superior latent heat and exceptional dual recyclability is presented. Easily accessible anhydride copolymers (e.g., propylene-maleic anhydride alternating copolymers), provide abundant reactive anhydride sites within the polymer matrix; polyethylene glycol serves as both the grafted phase change component and the crosslinker. The resulting SSPCMs attain a peak latent heat value of 156.8 J g-1 which surpasses all other reported recyclable crosslinked SSPCMs. The materials also exhibit certain flexibility and a tunable tensile strength ranging from 6.6 to 11.0 MPa. Beyond that, leveraging the reversible anhydride-alcohol crosslinks, the SSPCMs demonstrate dual recyclability through bond-exchange remolding and reversible-dissociation-enabled dissolving-recrosslinking without any reactive chemicals. Furthermore, by integrating solar-thermal conversion fillers like polydopamine nanoparticles, the potential of the system in efficient conversion, storage, and release of solar energy is highlighted.

3.
J Fungi (Basel) ; 10(1)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38248979

RESUMO

The characterization of natural fungal diversity impacts our understanding of ecological and evolutionary processes and can lead to novel bioproduct discovery. Russula and Lactarius, both in the order Russulales, represent two large genera of ectomycorrhizal fungi that include edible as well as toxic varieties. Based on morphological and phylogenetic analyses, including nucleotide sequences of the internal transcribed spacer (ITS), the 28S large subunit of ribosomal RNA (LSU), the second largest subunit of RNA polymerase II (RPB2), the ribosomal mitochondrial small subunit (mtSSU), and the translation elongation factor 1-α (TEF1-α) gene sequences, we here describe and illustrate two new species of Russula and one new species of Lactarius from southern China. These three new species are: R. junzifengensis (R. subsect. Virescentinae), R. zonatus (R. subsect. Crassotunicatae), and L. jianyangensis (L. subsect. Zonarii).

4.
Plants (Basel) ; 12(22)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38005750

RESUMO

To explore the contribution of microorganisms to forest ecosystem function, we studied the ectomycorrhizal (ECM) fungal and soil bacterial community of the five typical tree species (Pinus massoniana, PM; Castanopsis carlesii, CC; Castanopsis eyrei, CE; Castanopsis fargesii, CF; and Keteleeria cyclolepis, KC) at the Junzifeng National Nature Reserve. The results indicated that the ECM fungal and soil bacterial diversity of CC and CF was similar, and the diversity rates of CC and CF were higher than those of PM, CE, and KC. Cenococcum geophilum and unclassified_Cortinariaceae II were the most prevalent occurring ECM fungi species in the five typical tree species, followed by unclassified_Cortinariaceae I and Lactarius atrofuscus. In bacteria, the dominant bacterial genera were Acidothermus, Bradyrhizobium, Acidibacter, Candidatus_Solibacter, Candidatus_Koribacter, Roseiarcus, and Bryobacter. EMF fungi and soil bacteria were correlated with edaphic factors, especially the soil pH, TP, and TK, caused by stand development. The results show that the community characteristics of ECM fungi and bacteria in the typical tree species of the Junzifeng National Nature Reserve reflect the critical role of soil microorganisms in stabilizing forest ecosystems.

5.
Front Neurol ; 14: 1281412, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38164201

RESUMO

Background: Cerebral cavernous malformation (CCM) is a rare disease associated with a latent risk of intracranial hemorrhage. However, due to limited evidence, the safety of recommending intravenous tissue plasminogen activators for patients with acute stroke and CCM remains uncertain. Methods: Our study identified five patients with acute stroke and CCM treated between 2017 and 2023 across two hospitals. A comprehensive literature review was conducted, incorporating three similar case reports and two retrospective studies. Results: Among 30 patients reviewed, three exhibited symptomatic intracranial hemorrhage, two of whom were women. Additionally, three patients presented with calcification in their CCM, with two experiencing symptomatic intracranial hemorrhage. Conclusion: The observed incidence of symptomatic intracranial hemorrhage following intravenous tissue plasminogen activator administration appears to be elevated in patients with CCM. Therefore, before thrombolysis, a thorough evaluation of personalized risk-benefit ratios is crucial. Furthermore, conducting further research involving multiple centers and larger sample sizes is imperative to advance our understanding in this area, especially in identifying hemorrhage risk factors.

6.
Cardiovasc Drugs Ther ; 36(6): 1109-1119, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34491473

RESUMO

PURPOSE: Abdominal aortic aneurysm (AAA) rupture is one of the most common causes of mortality in cardiovascular diseases, but currently there is no approved drug for AAA treatment or prevention in the clinic. Naringenin (NGN) has been reported to have anti-AAA effects. However, water solubility and in vivo absorption of NGN are not satisfactory, which leads to its low bioavailability, thus affecting its pharmacological effects. In this project, the improving effects of isonicotinamide (INT) co-crystal and hydroxy propyl methyl cellulose (HPMC) or polyvinyl pyrrolidone (PVP) on the solubility, in vivo absorption, and anti-AAA effects of NGN were evaluated. METHODS: In the current study, co-crystals of naringenin-isonicotinamide (NGN-INT) were prepared, and effects of PVP or HPMC on precipitation rate, supersaturation, and bioavailability of NGN were explored. In addition, with or without HPMC supply, the effects of NGN-INT co-crystal on anti-AAA efficacy of NGN were investigated on an elastase-induced AAA mouse model, and the results were compared with the efficacy of the NGN crude drug. RESULTS: Our results demonstrate that NGN-INT formulation, compared to the NGN crude drug, enhanced the dissolution rate of NGN and significantly increased Cmax and AUC(0-∞) of NGN by 18 times and 1.97 times, respectively. Addition of PVP or HPMC in NGN-INT co-crystal further increased bioavailability of NGN in NGN-INT. The in vivo pharmacodynamic study showed that NGN-INT with HPMC significantly improved the inhibitory effects of NGN against AAA. CONCLUSION: NGN-INT significantly improved the absorption and aortic protective effects of NGN. The supersaturation-prolonging effect of HPMC further enhanced bioavailability and anti-AAA effects of NGN-INT.


Assuntos
Aneurisma da Aorta Abdominal , Camundongos , Animais , Aneurisma da Aorta Abdominal/tratamento farmacológico , Aneurisma da Aorta Abdominal/prevenção & controle , Derivados da Hipromelose/química , Solubilidade , Povidona/química
7.
Mitochondrial DNA B Resour ; 6(12): 3348-3349, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34778553

RESUMO

We sequenced the complete 17,209 bp mitochondrial genome (mitogenome) of Gonyosoma frenatum (Squamata: Colubridae) using next-generation sequencing. It consists of 13 PCGs, two ribosomal RNA genes, 22 transfer RNA genes, one non-coding region of an L-strand replication origin, and two control regions. The overall nucleotide composition was 34.7% of A, 24.8% of T, 12.3% of G, and 28.1% of C. The result of the phylogenetic analysis showed that G. frenatum, a member of Colubridae, is sister to other New World and Old World ratsnakes. The new data could help better understand the phylogenetic status of the genus Gonyosoma and the evolutionary history of Colubridae species.

8.
ACS Appl Mater Interfaces ; 13(16): 18454-18461, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33856763

RESUMO

Water-soluble, biodegradable, nonionic, and biocompatible polymers with multiple functional groups are highly desired for biomedical applications. Here, we report that water-soluble nonionic poly(d/l-serine) is chirality-controllable, biodegradation-controllable, and non-cytotoxic. Hence, it can be a highly sought-after alternative to the widely used poly(ethylene glycol), with an additional advantage of having multiple hydroxyl groups for further functionalization. As one example of its biomedical applications, poly(d/l-serine) demonstrated an obvious cryoprotective effect on the red blood cells. The usage of poly(d/l-serine) in the cryopreservation field would be of great promise to resolve the difficulties in separating cryoprotectants due to toxicity.


Assuntos
Crioprotetores/química , Crioprotetores/farmacologia , Peptídeos/química , Peptídeos/farmacologia , Água/química , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Humanos , Solubilidade
9.
RSC Adv ; 11(22): 13091-13096, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35423840

RESUMO

A drug-polymer crystalline inclusion complex (IC) is a novel solid form of drug, in which drug molecules form parallel channels, and linear polymer chains reside in these channels. In this study, we used carbamazepine (CBZ) as a model drug, and directly studied the effect of different types of guest polymers on the dissolution properties of drug-polymer ICs. We successfully prepared ICs formed from CBZ with hydrophilic poly(ethylene glycol) (PEG) and hydrophobic poly(ε-caprolactone) (PCL), respectively, and confirmed that these two drug-polymer ICs both had the same channel-type crystal structure as CBZ form II. During the dissolution test, CBZ-PEG IC showed a faster dissolution rate compared to CBZ form II under both sink and non-sink conditions. CBZ-PCL IC was confirmed to be more stable in aqueous medium, as the guest polymer PCL delayed its transformation to less-soluble crystals during dissolution.

10.
ACS Appl Mater Interfaces ; 12(47): 52603-52614, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33174414

RESUMO

Modulating and optimizing the diverse parameters of photocatalysts synergistically as well as exerting these advantages fully in photocatalytic reactions are crucial for the sufficient utilization of solar energy but still face various challenges. Herein, a novel and facile urea- and KOH-assisted thermal polymerization (UKATP) strategy is first developed for the preparation of defect-modified thin-layered and porous g-C3N4 (DTLP-CN), wherein the thickness of g-C3N4 was dramatically decreased, and cyano groups, nitrogen vacancies, and mesopores were simultaneously introduced into g-C3N4. Importantly, the roles of thickness, pores, and defects can be targetedly modulated and optimized by changing the mass ratio of urea, KOH, and melamine. This can remarkably increase the specific area, improve the light-harvesting capability, and enhance separation efficiency of photoexcited charge carriers, strengthening the mass transfer in g-C3N4. Consequently, the photocatalytic hydrogen evolution efficiency of the DTLP-CN (1.557 mmol h-1 g-1, λ > 420 nm) was significantly improved more than 48.5 times with the highest average apparent quantum yield (AQY) of 18.5% and reached as high as 0.82% at 500 nm. This work provides an effective strategy for synergistically regulating the properties of g-C3N4, and opens a new horizon to design g-C3N4-based catalysts for highly efficient solar-energy conversion.

11.
ACS Appl Mater Interfaces ; 12(35): 39063-39073, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32805927

RESUMO

The development of highly crystalline perovskite films with large crystal grains and few surface defects is attractive to obtain high-performance perovskite solar cells (PSCs) with good device stability. Herein, we simultaneously improve the power conversion efficiency (PCE) and humid stability of the CH3NH3PbI3 (CH3NH3 = MA) device by incorporating small organic molecule IT-4F into the perovskite film and using a buffer layer of PFN-Br. The presence of IT-4F in the perovskite film can successfully improve crystallinity and enhance the grain size, leading to reduced trap states and longer lifetime of the charge carrier, and make the perovskite film hydrophobic. Meanwhile, as a buffer layer, PFN-Br can accelerate the separation of excitons and promote the transfer process of electrons from the active layer to the cathode. As a consequence, the PSCs exhibit a remarkably improved PCE of 20.55% with reduced device hysteresis. Moreover, the moisture-resistive film-based devices retain about 80% of their initial efficiency after 30 days of storage in relative humidity of 10-30% without encapsulation.

12.
Materials (Basel) ; 13(10)2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32408503

RESUMO

In this paper, CoCrFeNiTix high entropy alloy (HEA) coatings were prepared on the surface of Q235 steel by laser cladding. The microstructure, microhardness, and corrosion resistance of the coatings were studied. The mechanism of their corrosion resistance was elucidated experimentally and by first-principles calculations. The results show that CoCrFeNiTi0.1 adopts a face-centered cubic (FCC) phase, CoCrFeNiTi0.3 exhibits an FCC phase and a tetragonal FeCr phase, and CoCrFeNiTi0.5 adopts an FCC phase, a tetragonal FeCr phase, and a rhombohedral NiTi phase. The FCC phase, tetragonal FeCr phase, rhombohedral NiTi phase, and hexagonal CoTi phase are all observed in the CoCrFeNiTi0.7 HEA. The alloys assume the dendritic structure that is typical of HEAs. Ni and Ti are enriched in the interdendritic regions, whereas Cr and Fe are enriched in the dendrites. With increasing Ti content, the hardness of the cladding layers also increases due to the combined effects of lattice distortion and dispersion strengthening. When exposed to a 3.5 wt.% NaCl solution, pitting corrosion is the main form of corrosion on the CoCrFeNiTix HEA surfaces. The corrosion current densities of CoCrFeNiTix HEAs are much lower than those of other HEAs. As the Ti content increases, the corrosion resistance is improved. Through X-ray photoelectron spectroscopy (XPS) and first-principles calculations, the origin of the higher corrosion resistance of the coatings is connected to the presence of a dense passivation film. In summary, the corrosion resistance and mechanical properties of CoCrFeNiTi0.5 alloy are much better than the other three groups, which promotes the development of HEA systems with high value for industrial application.

13.
Nanoscale ; 12(10): 6111-6120, 2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32129398

RESUMO

Multinary copper-based chalcogenide nanocrystals (NCs) as light-driven photocatalysts have attracted extensive research interest due to their great potential for generating sustainable energy without causing environmental concerns. However, systematic studies on the growth mechanism and related photocatalytic activities involving different valent metal ions (either M2+ or N3+) as foreign cations and monoclinic Cu1.94S NCs as the 'parent lattice' have rarely been carried out. In this work, we report an effective seed-mediated method for the synthesis of heterostructured Cu1.94S-MS NCs (M = Zn, Cd and Mn) and alloyed CuNS2 NCs (N = In and Ga). A typical cation exchange process took place prior to the growth of heterostructured NCs, while further inter-cation diffusion occurred only for the alloyed NCs. When compared with Cu1.94S NCs, all the heterostructured Cu1.94S-MS NCs and CuGaS2 NCs showed enhanced photocatalytic activities toward hydrogen production by water splitting, owing to their tailored optical band gaps and energy level alignments. Although optically favored, CuInS2 ANCs were not comparable to others due to their low conduction band minimum for the reduction of H2O to H2.

14.
J Phys Chem Lett ; 11(3): 927-934, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31957447

RESUMO

High power conversion efficiency can be realized by using a ternary bulk heterojunction with complementary absorption spectra in organic solar cells. However, as the development of nonfullerene acceptors with a broad absorption spectrum makes the absorption efficiency of the photovoltaic devices close to optimal, such a strategy needs modifying. In particular, charge transfer between the two acceptors is necessary to be considered. Herein, we purposely design a ternary system based on PTB7-Th:COi8DFIC:ITIC-4F. Though the presence of ITIC-4F in PTB7-Th:COi8DFIC could not broaden the absorption spectrum obviously, the formed cascade-energy-level alignment is beneficial for promoting and balancing exciton separation and charge transport between the donor and two acceptors and even between the acceptors. Insights into the charge transport route in the completed system are provided via using the techniques including photoluminescence spectroscopy and pump-probe photoconductivity spectroscopy. This work provides a new idea for designing highly efficient ternary organic solar cells.

15.
Nanotechnology ; 30(44): 445403, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31342934

RESUMO

The full utilization of incident light is vitally important for boosting the photoelectrochemical activity of photoelectrodes. Herein, we introduce Ni-BiVO4 nanoarrays for mediating the photoelectrochemical water splitting by optimizing the optical modes. Highly ordered Ni-BiVO4 nanoarrays were fabricated using a nanoimprinted AAO templating technique. By controlling the thickness of BiVO4, we efficiently regulate the photoelectrochemical activity, and the photocurrent was up to 0.91 mA cm-2 at 1.4 V versus Ag/AgCl under 100 mW cm-2 in the visible light, which is 3.25 times that of a flat Ni-BiVO4 electrode with the same deposition cycles of BiVO4. The optimal efficiency of a Ni-BiVO4 nanoarrray-based photoelectrode can be attributed to the optimal morphology, which has the lowest reflection, the strongest scattering and the induced strongest absorption for the incident light among the nanoarrays samples with different thickness of BiVO4. This work demonstrates the importance of the optimization of optical modes in the nanoarray photoelectrode in order to boost photoelectrochemical activity.

16.
Acta Pharm Sin B ; 9(1): 186-193, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30766790

RESUMO

Currently there is no successful platform technology for the sustained release of protein drugs. It seems inevitable to specifically develop new materials for such purpose, and hence the understanding of protein-material interactions is highly desirable. In this study, we synthesized cholesterol-grafted polyglutamate (PGA-g-Chol) as a hydrophobically-modified polypeptide, and thoroughly characterized its interaction with a model protein (human serum albumin) in the aqueous solution by using circular dichroism, fluorescence methods, and light scattering. With the protein concentration fixed at 5 µmol/L, adding PGA-g-Chol polymers into the solution resulted in continuous blue shift of the protein fluorescence (from 339 to 332 nm), until the polymer molar concentration reached the same value as the protein. In contrast, the un-modified polyglutamate polymers apparently neither affected the protein microenvironment nor formed aggregates. Based on the experimental data, we proposed a physical picture for such protein-polymer systems, where the polymer first bind with the protein in a 1:1 molar ratio via a fraction of their hydrophobic pendant cholesterol resides along the polymer chain. In this protein/polymer complex, there are excess unbound cholesterol residues. As the polymer concentration increases, the polymers form multi-polymer aggregates around 200 nm in diameter via the same hydrophobic cholesterol residues. The protein/polymer complex also participate in the aggregation via their excess cholesterol residues, and consequently the proteins are encapsulated into the nanoparticles. The encapsulation was also found to increase the thermal stability of the model protein.

17.
RSC Adv ; 9(34): 19772-19779, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-35519398

RESUMO

Controllable growth of perovskite nanowires is very important for various applications in optical and electrical devices. Although significant progress has been achieved in the solution method, a deep understanding of the mechanics of growing perovskite nanowires is still lacking. Herein, we developed an electrochemical method for growing the perovskite nanowires and studied the growth processes systematically. The initial nucleation and crystal growth could be controlled by simply varying the additive solvents, thus leading to two stable size ratio distributions of the perovskite nanowires. Further, with compositional engineering, the bandgap of the perovskites could be tuned from 1.59 eV to 3.04 eV. All the as-grown perovskite nanowires displayed a unique structure with high crystallization quality, contributing to a very high responsivity of 2.1 A W-1 and a large on/off ratio of 5 × 103 for the photodetectors based on the CH3NH3PbBr3 nanowires. All of these findings demonstrate that the optimized solution method offers a new approach to synthesize perovskite nanowires for applications in photoelectric devices.

18.
RSC Adv ; 9(37): 21318-21322, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35521341

RESUMO

Sodium foscarnet is an antiviral drug against cytomegalovirus retinitis, and clinically it is used via frequent intravitreal injection which causes various ocular complications. Here we propose to use benzathine foscarnet in a new salt form with much lower aqueous solubility, and as a potential long-acting intravitreally injectable solid form for foscarnet. Benzathine foscarnet (1 : 1) microcrystals were synthesized and evaluated both in vitro and in vivo. The aqueous solubility of benzathine foscarnet was 14.2 mM, which is in between those of the currently-used sodium foscarnet and our previously-reported calcium foscarnet salt. In a rabbit model, the injected microcrystals last for about 3 weeks in the vitreous, suggesting its solubility and dissolution profile is appropriate for its intended use. However, the injected benzathine foscarnet microcrystals also caused adverse effects in vivo.

19.
Nanoscale ; 11(1): 158-169, 2018 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-30525146

RESUMO

Multinary copper-based chalcogenides exhibit significant performance in photocatalytic hydrogen evolution due to their suitable optical bandgap for visible light absorption and environmentally friendly character. Herein, high-quality wurtzite CuGaS2 (CGS) nanocrystals (NCs) were synthesized by using a one-step heating-up process without any injection, and the morphology could be tuned from one-dimensional (1D) to two-dimensional (2D) by precise choice of surface ligands and gallium precursors. The formation mechanism of CGS NCs was studied comprehensively by means of the temporal-evolution of the morphology, crystal structure and optical absorption results. The reaction started from djurleite Cu31S16 NCs, and then proceeded with the formation of Cu31S16-CGS heteronanostructures (HNS), and finally the transformation from HNS to monophasic CGS nanorods took place with prolonging of the synthesis time. The optical bandgap and the energy level of the different-dimensional CGS NCs exhibited a strong dependence on the morphology change, which correlated with the percentage of the exposed {001} and {100} facets. The theoretical calculation based on density functional theory (DFT) revealed that the (001) surface facilitated the charge transport rather than the (100) surface, which was consistent with the electrochemical impedance spectroscopy (EIS) results. As a result, the 2D CGS nanoplates with more exposed {001} facets exhibited an attractive photocatalytic hydrogen production activity under simulated solar illumination as compared to 1D and quasi-2D counterparts. This study demonstrates that control over the dimension of I-III-V group semiconductor NCs could lead to a significant improvement of the photocatalytic hydrogen evolution.

20.
Int J Pharm ; 543(1-2): 121-129, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29597033

RESUMO

Nevirapine (NVP) is recommended by WHO as the antiretroviral treatment to prevent HIV passing from mother to child. However, the once-daily oral administration results in poor patient compliance, and a long-acting injectable form of NVP is desirable. Using single-crystal X-ray diffraction and other characterization methods, we demonstrated NVP can form crystalline inclusion complex (IC) with the biodegradable hydrophobic poly(ε-caprolactone) (PCL), and investigated the potential of the NVP-PCL IC microparticles as a long-acting injectable solid form. Compared with pure NVP crystals and NVP/polylactide microparticles, the NVP-PCL IC crystals showed significantly decreased solubility and slower dissolution rate, making it more suitable to be developed to achieve sustained-release profiles. In addition, the NVP-PCL IC microparticles with an average diameter below 10 µm can be conveniently prepared by spray drying and are found to be easily injectable through a 25G needle. These results demonstrated the possibility of using drug-polymer IC microparticles as long-acting injectable forms, providing a new approach to design sustained-release drug products.


Assuntos
Fármacos Anti-HIV/química , Nevirapina/química , Poliésteres/química , Cristalização , Preparações de Ação Retardada/química , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Injeções , Solubilidade
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