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In this study, it is aimed to utilize advantages of additive manufacturing in preparation of laminated composite materials with no need of mold. To do so, the composite was prepared by applying carbon fiber fabric on a polylactic acid (PLA) core produced by additive manufacturing. 2 and 3-laminated samples were used for weight drop tests by applying 50 J of impact energy. Complete damage was observed with 2-laminated samples, while partial damage occurred on 3-laminated samples with 23.63 J absorbed energy. Moreover, the force-time plot showed a characteristic pattern of the composite structure. Tensile tests revealed that the samples exhibited brittle fracture with limited elongation and had no contribution of the PLA core to the stress-strain behavior. However, two stages were observed in the stress-strain curve of three-point bending test which were attributed to the thermoset carbon fiber laminate layer and thermoplastic PLA core. A maximum bending stress was determined as 138.81 MPa. [ABSTRACT FROM AUTHOR]

The aim of this study was to develop heparin sodium loaded microneedle patches using different compositions of polyvinyl alcohol polymer and sorbitol. A vacuum micromolding technique was used to fabricate microneedle patches while heparin sodium was loaded into needle tips. Physical features of patches were evaluated by measuring thickness, width, folding endurance and swelling percentage. Patches were also characterised by optical microscopy and scanning electron microscopy to determine the microneedle length and surface morphologies. A preliminary assessment of the microneedle performance was studied by examining the in-vitro insertion to the parafilm and recording the in-vitro drug release profile. In-vivo activity of patches was confirmed by measuring activated partial thromboplastin time and histological examination of the micropierced skin tissues. Prepared patches were clear, smooth; uniform in appearance; with sharp pointed microprojections and remained intact after 1000 folding. The microneedles were stiffer in nature, as they reproduce microcavities in the parafilm membrane following hand pushing without any structural loss. Insertion study results showed successful insertion of microneedles into the parafilm. Disrupted stratum corneum evident from histological examination confirmed successful insertion of the microneedle without affecting the vasculature. In-vitro release study confirmed ∼92% release of the loaded drug within 120 min. A significant prolongation of activated partial thromboplastin time (4 folds as compared to negative control) was recorded following the application of heparin sodium loaded microneedle patch onto rabbit skin. In conclusion microneedles are a valuable drug delivery system, benefiting the patients with minimal skin invasion and also allowing self-administration of heparin sodium in a sustained release manner for the management of chronic ailments. [ABSTRACT FROM AUTHOR]

The aim of this study was to fabricate Bacillus Calmette–Guérin (BCG)-loaded microneedle patches using micromould casting technique and compare their efficacy with the injectable counterparts. The microneedle patches were formulated using sodium alginate (10% w/v) and trehalose (20% of polymer). The patches were characterised using optical microscopy, scanning electron microscopy and folding endurance. Serum IgG, TLC, granulocyte count, lymphocyte count and CRP were assessed and results were compared to that of intradermal injections alongside controls. The results showed that polymeric patches had a thickness of 0.8 mm, microneedle projections of 272 ± 12 µm and folding endurance of more than 300. Based on haematological and IgG ELISA assays, microneedle-based BCG administration significantly activated the immune cells and induced production of lymphocytes, granulocytes and peptide-specific IgG in immunised rats that were comparable to injectable counterparts. There was an increase in IgG antibodies from 3 g/L to 5.98 g/L and an increase in leucocytes from 2.6 × 109/L to 18.45 × 109/L. There was also an increase in granulocytes from 14.4% to 29.15% and lymphocyte count from 58.75% to 85.3%. It was concluded that BCG-coated polymeric microneedle patches are suitable for the transdermal delivery of vaccine without inducing discomfort usually observed with injections. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the application of piezoelectric inkjet technology in the preparation of custom-made indomethacin (IMC) films. Indomethacin solutions with and without PVP were printed onto polymeric sheets using a commercial inkjet printer. Drug loading was varied by selecting a machine parameter different dots per inches (DPIs). The printed patches were evaluated for particulate morphologies, drug loading, in vitro release and ex vivo skin permeation and anti-inflammatory effects using hind paw inflammation model. Calculated drug loaded in 2 × 2 cm2 patches of IMC of 96, 300, and 600 DPIs were in the range of 40, 60, and 65 μg, respectively. Patches loaded with IMC alcoholic solution showed crystalline structures observed by scanning electron microscopy and the addition of PVP in solution turned it to amorphous form. The drug release profile showed 60–70% of total drug released in 3 h. Permeation studies showed 40–50% of total drug loaded permeated through rat skin using Franz cells. Patches with higher printing density 600 DPI showed anti-inflammatory effect in hind paw inflammation model studies. This study has shown the potential of personalized medicine in which a calculated amount of drug can be delivered to patients by piezoelectric technology. [ABSTRACT FROM AUTHOR]

In this work, the V-shaped microfluidic junction (VMJ) device technique with gas/liquid interface was used to prepare textured polymer nanospheres from bubble bursting for drug delivery. The polymer/dye solution, N2 gas, and a volatile liquid, perfluorohexane (PFH) were simultaneously fed using the tubes into the VMJ device. A high-pressure injection of N2 gas into the VMJ interacts with PFH and ethanol leading to the preparation of a microbubble system. Once bubbles are ejected from the VMJ outlet, nanospheres calve from the parent bubble. The collection temperature and the N2 gas pressure play a key role in the mechanism by which nanospheres are formed. In addition, the volatile liquid, PFH, is described as a significant surface modifier. The influence of the N2 gas pressure, collection temperature, and the volatile liquid flow rates on nanospheres size distribution and surface roughness were investigated using scanning electron microscopy. The results revealed that the N2 gas pressure and collection temperature are crucial in tailoring the size distribution of the nanospheres and that the nanospheres textured with PFH had significantly rougher surface. Nanospheres coated with Evans blue dye were prepared, and those collected at high temperature exhibited a very different dye release profile compared with those collected at lower temperatures. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Dexibuprofen (DXIBN) transdermal patches were formulated using various concentrations of selected polymeric excipients (matrix material; ethyl cellulose and polyvinylpyrrolidone, plasticizer (di-N-butyl phthalate), and a conventional permeation enhancer (almond oil)). Initial patch formulations were evaluated for their physiochemical properties (thickness, moisture uptake, final moisture content, and DXIBN content). Also, impact of patch components on resulting tensile strength andin vitropermeation were used to predict an optimal patch formulation using a quality-by-design (QbD) approach, which was subsequently evaluated and further compared with a commercial oral tablet dosage form forin vitroandin vivorelease (rabbit model). Initially formulated patches demonstrated uniform thickness (0.44 ± 0.02 cm), relatively low moisture uptake (7.87 ± 1.11 w/w %), and highly acceptable drug loading values (100.0 ± 0.026%). The tensile strength of patches increased significantly with matrix polymer concentration and to a lesser degree with increase in plasticizer and permeation enhancer content, although these affected the permeation of DXIBN. Predicted properties (tensile strength and DXIBN steady-state flux) for the QbD-optimized formulation were in close agreement to experimental results. The QbD optimal patch formulation behavior differed significantly from the commercial tablet formulationin vivo.Such model-based predictions (QbD approach) will reduce cost and time in formulation development sciences. [ABSTRACT FROM PUBLISHER]