Camposwatson6030

Photodynamic antimicrobial chemotherapy (PACT) has advantages of strong targeting, low resistance to drugs. Electrospinning nanofibers is favorable for wound healing. The combination of PACT and electrospinning nanofibers is appropriate for wound healing, especially infected wound. In our study, indocyanine green (ICG) as photosensitizer had obvious inhibition effects on two antibiotic-resistant bacteria, Methicillin-resistant Staphylococcus aureus (MRSA) and Meropenem-resistant Pseudomonas aeruginosa (MRPA). The optimized electrospinning solution consisted of 2% (w/v) chitosan and 7% (w/v) PVA. The nanofibers observed by scanning electron microscope showed a three-dimensional cross-network with smooth surface, the water absorption ratio of the nanofibers was up to 210%. Fourier transform infrared spectrum and X-ray diffraction showed that the intermolecular hydrogen bonding happened between chitosan and PVA in electrospinning process, which was favorable for the formation of nanofibers. ICG released rapidly from the surface of the nanofibers first and then released continuously. The photodynamic nanofibers could inhibit the bacteria and decreased the F4/80 expression of MRSA-infected rats. The improved effects of wound healing were evaluated with the morphology, wound healing radio, the increased expression of cluster of differentiation 31 (CD31), the decreased level of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). The photosensitizer-loaded electrospinning nanofibers provide a novel promising option for treatment of infected wound.Dry powder inhaler (DPI) development is limited by the time- and labor-consuming in vitro lung deposition test. It's highly desirable to find an easy tool for DPI formulation screening. Sodium L-lactate manufacturer Dynamic powder rheological properties seem to present many advantages, however, the adoptability needs to be verified. Drug charge is an important parameter especially for DPI formulation design but how it affects the process of pulmonary drug delivery is unavailable. Therefore, the objective of this study is to explore the influence of drug charge on DPI powders, further testing the potentials of powder properties for downstream deposition behavior prediction. Taking five differently charged drugs as model, influence of drug charge on uniformity, rheological and aerodynamic properties of the mixtures were investigated systemically. It was found that mometasone furoate with near neutral charge presented better content homogeneity, while significantly decreased recovery was noted for charged drugs, such as positively charged drug (salbutamol sulphate and indacaterol maleate) mixtures and negatively charged drug (budesonide and fluticasone propionate) mixtures. Moreover, drug charge also influenced flowability and cohesion of their admixture with lactose. As for the downstream deposition, neutral drugs presented higher fine particle fraction (FPF), followed by positively charged drugs and negatively charged drugs. Good correlations between basic flowability energy, aeration energy, Permeability and FPF were established irrespective of different drugs. Principal component analysis results suggested flowability had a greater influence on FPF when mixtures were less cohesive. In conclusion, this study demonstrated drug charge can influence physicochemical, rheological and aerodynamic properties of the admixture, and DPIs' dynamic properties could be used as potential tools to predict downstream deposition with good accuracy.Efficient approach was established to improve the drug delivery performance of the pH-triggered prodrug nanoparticles by introducing a polycation block as a pH-sensitive gatekeeper. With the help of the poly(2-(diisopropylamino)ethyl methacrylate) (PDPA) block as a pH-sensitive shell gatekeeper, the proposed core-shell-corona PEG43-b-PDPA65-b-PFPMA36-DOX nanoparticles possessed a higher drug release rate in the simulated acidic tumor intracellular micro-environment while a lower premature drug leakage in the simulated weak basic normal physiological medium, compared with the core-shell PEG43-b-PFPMA36-DOX nanoparticles. The proposed strategy is expected to design high-performance drug delivery systems (DDSs) for tumor treatment, with improved anticancer efficacy but minimized toxic side effects.Electrospun nanofiber is a very attractive material which can be used as the support to form multiple-drug dosage. Understanding the dissolution process of different active drug ingredients released from electrospun fibers is of great importance to control and evaluate the quality of medicated nanofibers. Here we present the first study of on-line automatic analysis of dissolution of multiple drugs in electrospun fiber mats. Single-needle electrospinning technology is utilized to combine polymers, hydrophilic polyvinylpyrrolidone (PVP) and hydrophobic polycaprolactone (PCL) as carrier to load three poorly water-soluble non-steroidal anti-inflammatory drugs (paracetamol, nimesulide, and ibuprofen). The loading of the drugs in PVP/PCL electrospun fibers are characterized by various techniques, including scanning electron microscopy, X-ray diffraction, Fourier infrared spectroscopy and differential scanning calorimetry. The in vitro dissolution is investigated by our home-made portable analyzer, which can simultaneously on-line determine multiple drugs released from the nanofibers by a single step. The analysis shows a wide linear detection range of the drugs with limit-of-detection (LOD) down to μg/mL-level. The dissolution profiles of three ingredients in nanofibers can be monitored every thirty seconds from the beginning to the end in the entire dissolution process from only one HSCE run. The kinetic information of the dissolution, including the dissolution curve, characteristic dissolution time and dissolution efficiency, is obtained and evaluated for different dissolution media, drug loading content and the ratio of PVP/PCL. Our study provides a promising method for rapid and accurate dissolution testing of nanofiber-based drugs, and would extend the applications of separation techniques in pharmaceutical analysis.