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1.
J Colloid Interface Sci ; 678(Pt C): 717-725, 2024 Sep 16.
Article in English | MEDLINE | ID: mdl-39307060

ABSTRACT

Layered double hydroxide (LDH) serves as an innovative catalyst for water electrolysis, showcasing outstanding performance in the oxygen evolution reaction (OER) under alkaline conditions. However, it faces challenges due to its low electrical conductivity and limited accessibility to active sites. In this work, the flexibility advantages of disordered amorphous and ordered crystals in NiFe LDH were combined to improve OER performance and maintain long-term stability. This combination induces a variety of effects, including improving the intrinsic activity, changing the OER mechanism from adsorb evolution mechanism (AEM) to lattice oxygen mechanism (LOM), and promoting the reaction kinetics of the catalyst. Moreover, the porous structure of NiFe LDH can efficiently alleviate the issue of local acidic environment induced by prolonged OER reaction, satisfying the criteria for long-term stability. Therefore, the NiFe-2.0 LDH catalyst only requires an ultralow overpotential of 189 mV at a current density of 10 mA cm-2 with Tafel slope of 43 mV dec-1. More importantly, the catalyst not only displays excellent electrocatalytic activity with an overpotential of 289 mV but also represents an outstanding stability over 80 h at an ultra-high current density of 1 A cm-2. This study provides a promising strategy for optimizing the catalytic activity and stability of catalyst at ampere current density, which is expected to achieve commercial applications.

2.
Int J Pharm ; 665: 124668, 2024 Nov 15.
Article in English | MEDLINE | ID: mdl-39245086

ABSTRACT

The utilization of three-dimensional (3D) printing technology is prevalent in the fabrication of oral sustained release preparations; however, there is a lack of research on 3D-printed osmotic pump tablets. A 3D-printed core-shell structure bezafibrate osmotic pump tablet was developed based on the characteristics of rapid absorption and short half-life of bezafibrate, utilizing semisolid extrusion (SSE) 3D printing technology. First, the properties of different shell materials were investigated to define the composition of the shell, and ultimately, the optimal formulation was found to be ethyl cellulose:cellulose acetate:polyethylene glycol = 2:1:2. The formulation of the tablet core was defined based on the printing performance and release behavior. The formulation consisted of bezafibrate, lactis anhydrous, sodium bicarbonate, sodium alginate, polyethylene oxide and sodium dodecyl sulfate at a ratio of 400:400:300:80:50:50. The tablet was capable of achieving zero-order release. The physicochemical properties were also characterized. The pharmacokinetic data analysis indicated that there were no statistically significant differences in the pharmacokinetic parameters between the 3D-printed tablets and the reference listed drugs. There was a strong correlation between the in vitro and in vivo results for the 3D-printed tablets. The results showed that SSE printing is a practical approach for manufacturing osmotic pump tablets.


Subject(s)
Cellulose , Drug Liberation , Osmosis , Polyethylene Glycols , Printing, Three-Dimensional , Tablets , Polyethylene Glycols/chemistry , Cellulose/chemistry , Cellulose/analogs & derivatives , Delayed-Action Preparations/chemistry , Technology, Pharmaceutical/methods , Excipients/chemistry , Animals , Alginates/chemistry , Chemistry, Pharmaceutical/methods , Male , Drug Compounding/methods
3.
Vis Comput Ind Biomed Art ; 6(1): 18, 2023 Sep 28.
Article in English | MEDLINE | ID: mdl-37768387

ABSTRACT

Obtaining a 3D feature description with high descriptiveness and robustness under complicated nuisances is a significant and challenging task in 3D feature matching. This paper proposes a novel feature description consisting of a stable local reference frame (LRF) and a feature descriptor based on local spatial voxels. First, an improved LRF was designed by incorporating distance weights into Z- and X-axis calculations. Subsequently, based on the LRF and voxel segmentation, a feature descriptor based on voxel homogenization was proposed. Moreover, uniform segmentation of cube voxels was performed, considering the eigenvalues of each voxel and its neighboring voxels, thereby enhancing the stability of the description. The performance of the descriptor was strictly tested and evaluated on three public datasets, which exhibited high descriptiveness, robustness, and superior performance compared with other current methods. Furthermore, the descriptor was applied to a 3D registration trial, and the results demonstrated the reliability of our approach.

5.
Adv Sci (Weinh) ; 9(23): e2201633, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35678109

ABSTRACT

Mechanical energy-induced CO2 reduction is a promising strategy for reducing greenhouse gas emissions and simultaneously harvesting mechanical energy. Unfortunately, the low energy conversion efficiency is still an open challenge. Here, multiple-pulse, flow-type triboelectric plasma with dual functions of harvesting mechanical energy and driving chemical reactions is introduced to efficiently reduce CO2 . CO selectivity of 92.4% is achieved under normal temperature and pressure, and the CO and O2 evolution rates reach 12.4 and 6.7 µmol h-1 , respectively. The maximum energy conversion efficiencies of 2.3% from mechanical to chemical energy and 31.9% from electrical to chemical energy are reached. The low average electron energy in triboelectric plasma and vibrational excitation dissociation of CO2 with low barrier is revealed by optical emission spectra and plasma simulations, which enable the high energy conversion efficiency. The approach of triboelectric plasma reduction reported here provides a promising strategy for efficient utilization of renewable and dispersed mechanical energy.

6.
Int J Pharm ; 618: 121679, 2022 Apr 25.
Article in English | MEDLINE | ID: mdl-35314275

ABSTRACT

A customized implantable drug delivery system with the dual functions of playing a supporting role and providing continuous bacteriostasis is of great importance during the treatment of bone defect diseases. The main objective of this study was to explore the potential of using three-dimensional (3D) printing technologies to fabricate customized implants. Ciprofloxacin hydrochloride (Cipro) was chosen as the model drug, and two printing technologies, semisolid extrusion (SSE) and fused deposition modeling (FDM) were introduced. Six kinds of implants with customized irregular shapes were printed via FDM technology. Two kinds of implants with customized dosages were constructed via SSE technology. In addition, three kinds of implants with customized internal structures were produced via FDM and SSE technologies. The data for morphology, dimensions and mechanical properties demonstrated satisfactory printability and good printing accuracy when applying SSE and FDM technologies to produce the customized implants. The dissolution curves indicated that the desired customized drug release could be achieved by designing the specific internal structures. The biocompatibility examination showed that the printed implants possessed outstanding biocompatibility. In conclusion, all results suggested that 3D printing technologies provide a feasible method and novel strategy to fabricate customized implantable drug delivery systems.


Subject(s)
Drug Delivery Systems , Printing, Three-Dimensional , Ciprofloxacin , Drug Delivery Systems/methods , Drug Liberation , Pharmaceutical Preparations , Prostheses and Implants , Technology, Pharmaceutical
7.
Acta Pharm Sin B ; 11(8): 2488-2504, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34567958

ABSTRACT

Three-dimensional printing is a technology that prints the products layer-by-layer, in which materials are deposited according to the digital model designed by computer aided design (CAD) software. This technology has competitive advantages regarding product design complexity, product personalization, and on-demand manufacturing. The emergence of 3D technology provides innovative strategies and new ways to develop novel drug delivery systems. This review summarizes the application of 3D printing technologies in the pharmaceutical field, with an emphasis on the advantages of 3D printing technologies for achieving rapid drug delivery, personalized drug delivery, compound drug delivery and customized drug delivery. In addition, this article illustrates the limitations and challenges of 3D printing technologies in the field of pharmaceutical formulation development.

8.
J Pharm Sci ; 110(11): 3678-3689, 2021 11.
Article in English | MEDLINE | ID: mdl-34371072

ABSTRACT

A suitable drug-loaded implant delivery system that can effectively release antibacterial drug in the postoperative lesion area and help repair bone infection is very significant in the clinical treatment of bone defect. The work was aimed to investigate the feasibility of applying three-dimensional (3D) printing technology to prepare drug-loaded implants for bone repair. Semi-solid extrusion (SSE) and Fuse deposition modeling® (FDM) technologies were implemented and ciprofloxacin (CIP) was chosen as the model drug. All of the implants exhibited a smooth surface, good mechanical properties and satisfactory structural integrity as well as accurate dimensional size. In vitro drug release showed that the implants made by 3D printing technologies slowed down the initial drug burst effect and expressed a long-term sustained release behavior, compared with the implants prepared with traditional method. In addition, the patient-specific macrostructure implants, consisting of interconnected and different shapes pores, were created using unique lay down patterns. As a result, the weakest burst release effect and the sustained drug release were achieved in the patient-specific implants with linear pattern. These results clearly stated that 3D printing technology offers a viable approach to prepare control-releasing implants with patient-specific macro-porosity and presents novel strategies for treating bone infections.


Subject(s)
Ciprofloxacin , Technology, Pharmaceutical , Drug Delivery Systems , Drug Liberation , Humans , Printing, Three-Dimensional , Tablets
9.
Int J Pharm ; 596: 120201, 2021 Mar 01.
Article in English | MEDLINE | ID: mdl-33539997

ABSTRACT

Patient responses to doses vary widely, and affording limited doses to such a diverse population will inevitably yield unsatisfactory therapeutic effects and even adverse effects. In Particular, there is an urgent demand for a dynamic dose-control platform for pediatric patients, many of whom require diverse doses and flexible dose adjustments. The aim of this study was to explore the possibility of using a drop-on-powder (DoP) technology-based desktop 3D printer to build a dynamic dose-control platform for theophylline (TP) and metoprolol tartrate (MT). In addition, the impact of drug loading patterns on the accuracy of dose regulation was also assessed. All of the printed tablets exhibited good mechanical properties and satisfactory structural integrity. On printing tablets with target drug doses, the accuracy was in the range of 91.2~108% with a small variation coefficient in the range of 0.5~3.2%. Compared with traditional divided-dose methods, drop-on-powder 3D printing technology exhibited higher accuracy in dose regulation, but had less impact on the in vitro drug release behavior. The results in this work clearly indicate the possibility and ability of DoP technology as a promising method for constructing a dynamic dose-control platform for the fabrication of personalized medicines for pediatric patients.


Subject(s)
Printing, Three-Dimensional , Theophylline , Child , Drug Liberation , Humans , Powders , Tablets , Technology, Pharmaceutical
10.
AAPS PharmSciTech ; 22(1): 37, 2021 Jan 06.
Article in English | MEDLINE | ID: mdl-33409925

ABSTRACT

In 2017, there are 451 million people with diabetes worldwide. These figures were expected to increase to 693 million by 2045. The research and development of hypoglycemic drugs has become a top priority. Among them, sulfonylurea hypoglycemic drugs such as glipizide are commonly used in non-insulin-dependent type II diabetes. In order to adapt to the wide range of hypoglycemic drugs and the different individual needs of patients, this topic used glipizide as a model drug, and prepared glipizide preparations with 3D printing technology. The purpose of this study was to investigate the prescription applicability and control-release behavior of structure and explore the application prospects of 3D printing personalized drug delivery formulations. This article aims to establish a production process for personalized preparations based on 3D printing technology. The process is easy to obtain excipients, universal prescriptions, flexible dosages, exclusive customization, and integrated automation. In this paper, the UV method was used to determine the in vitro release and content analysis method of glipizide; the physical and chemical properties of the glipizide were investigated. The established analysis method was inspected and evaluated, and the experimental results met the methodological requirements. Glipizide controlled-release tablets were prepared by the semisolid extrusion (SSE) method using traditional pharmaceutical excipients combined with 3D printing technology. The formulation composition, in vitro release, and printing process parameters of the preparation were investigated, and the final prescription and process parameters (traveling speed 6.0-7.7 mm/s and extruding speed 0.0060-0.0077 mm/s) were selected through comprehensive analysis. The routine analysis results of the preparation showed that the performance of the preparation meets the requirements. In order for 3D printing technology to play a better role in community medicine and telemedicine, this article further explored the universality of the above prescription and determined the scope of application of prescription drugs and dosages. Glipizide, gliclazide, lornoxicam, puerarin, and theophylline were used as model drugs, and the range of drug loading percentage was investigated. The results showed when the solubility of the drug is 9.45 -8.34 mg/mL, and the drug loading is 3-43%; the release behavior is similar.


Subject(s)
Dosage Forms , Precision Medicine , Printing, Three-Dimensional , Technology, Pharmaceutical/methods , Diabetes Mellitus, Type 2/drug therapy , Excipients/chemistry , Glipizide/chemistry , Glipizide/therapeutic use , Humans , Hypoglycemic Agents/chemistry , Hypoglycemic Agents/therapeutic use , Solubility , Sulfonylurea Compounds/chemistry , Sulfonylurea Compounds/therapeutic use , Tablets
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