Liposomal Encapsulation of Carvacrol to Obtain Active Poly (Vinyl Alcohol) Films.

Lecithins of different origins and compositions were used for the liposomal encapsulation of carvacrol within the framework of the development of active films for food packaging. Liposomes were incorporated into aqueous polymeric solutions from fully (F) and partially (P) hydrolysed Poly (vinyl alcohol) (PVA) to obtain the films by casting. The particle size distribution and ζ-potential of the liposomal suspensions, as well as their stability over time, were evaluated. Liposomal stability during film formation was analysed through the carvacrol retention in the dried film and the film microstructure. Subtle variations in the size distributions of liposomes from different lecithins were observed. However, the absolute values of the ζ-potential were higher (-52, -57 mV) for soy lecithin (SL) liposomes, followed by those of soy lecithin enriched with phosphatidylcholine (SL-PC) (-43, -50 mV) and sunflower lecithin (SFL) (-33, -38 mV). No significant changes in the liposomal properties were observed during the study period. Lyotropic mesomorphism of lipid associations and carvacrol leakage occurred to differing extents during the film drying step, depending on the membrane lipid composition and surface charge. Liposomes obtained with SL-PC were the most effective at maintaining the stability of carvacrol emulsion during film formation, which led to the greatest carvacrol retention in the films, whereas SFL gave rise to the least stable system and the highest carvacrol losses. P-PVA was less sensitive to the emulsion destabilisation due to its greater bonding capacity with carvacrol. Therefore, P-PVA with carvacrol-loaded SL-PC liposomes has great potential to produce active films for food packaging applications.

Composites Based on Gellan Gum, Alginate and Nisin-Enriched Lipid Nanoparticles for the Treatment of Infected Wounds.

Due to growing antimicrobial resistance to antibiotics, novel methods of treatment of infected wounds are being searched for. The aim of this research was to develop a composite wound dressing based on natural polysaccharides, i.e., gellan gum (GG) and a mixture of GG and alginate (GG/Alg), containing lipid nanoparticles loaded with antibacterial peptide-nisin (NSN). NSN-loaded stearic acid-based nanoparticles (NP_NSN) were spherical with an average particle size of around 300 nm and were cytocompatible with L929 fibroblasts for up to 500 µg/mL. GG and GG/Alg sponges containing either free NSN (GG + NSN and GG/Alg + NSN) or NP_NSN (GG + NP_NSN and GG/Alg + NP_NSN) were highly porous with a high swelling capacity (swelling ratio above 2000%). Encapsulation of NSN within lipid nanoparticles significantly slowed down NSN release from GG-based samples for up to 24 h (as compared to GG + NSN). The most effective antimicrobial activity against Gram-positive Streptococcus pyogenes was observed for GG + NP_NSN, while in GG/Alg it was decreased by interactions between NSN and Alg, leading to NSN retention within the hydrogel matrix. All materials, except GG/Alg + NP_NSN, were cytocompatible with L929 fibroblasts and did not cause an observable delay in wound healing. We believe that the developed materials are promising for wound healing application and the treatment of bacterial infections in wounds.

Optimization of the Preparation of Magnetic Liposomes for the Combined Use of Magnetic Hyperthermia and Photothermia in Dual Magneto-Photothermal Cancer Therapy.

In this work, we aimed to develop liposomal nanocomposites containing citric-acid-coated iron oxide magnetic nanoparticles (CMNPs) for dual magneto-photothermal cancer therapy induced by alternating magnetic field (AMF) and near-infrared (NIR) lasers. Toward this end, CMNPs were encapsulated in cationic liposomes to form nano-sized magnetic liposomes (MLs) for simultaneous magnetic hyperthermia (MH) in the presence of AMF and photothermia (PT) induced by NIR laser exposure, which amplified the heating efficiency for dual-mode cancer cell killing and tumor therapy. Since the heating capability is directly related to the amount of entrapped CMNPs in MLs, while the liposome size is important to allow internalization by cancer cells, response surface methodology was utilized to optimize the preparation of MLs by simultaneously maximizing the encapsulation efficiency (EE) of CMNPs in MLs and minimizing the size of MLs. The experimental design was performed based on the central composite rotatable design. The accuracy of the model was verified from the validation experiments, providing a simple and effective method for fabricating the best MLs, with an EE of 87% and liposome size of 121 nm. The CMNPs and the optimized MLs were fully characterized from chemical and physical perspectives. In the presence of dual AMF and NIR laser treatment, a suspension of MLs demonstrated amplified heat generation from dual hyperthermia (MH)-photothermia (PT) in comparison with single MH or PT. In vitro cell culture experiments confirmed the efficient cellular uptake of the MLs from confocal laser scanning microscopy due to passive accumulation in human glioblastoma U87 cells originated from the cationic nature of MLs. The inducible thermal effects mediated by MLs after endocytosis also led to enhanced cytotoxicity and cumulative cell death of cancer cells in the presence of AMF-NIR lasers. This functional nanocomposite will be a potential candidate for bimodal MH-PT dual magneto-photothermal cancer therapy.

Liposomal drug delivery of Aphanamixis polystachya leaf extracts and its neurobehavioral activity in mice model.

Neurodegenerative diseases (Alzheimer's, Parkinson's etc.) causes brain cell damage leading to dementia. The major restriction remains in delivering drug to the central nervous system is blood brain barrier (BBB). The aim of this study was to develop a liposomal drug delivery system of Aphanamixis polystachya leaf extract for the treatment of neurodegenerative diseases such as Alzheimer's and Parkinson's disease. In this study GC-MS analysis is used to determine major constituents of Aphanamixis polystachya leaf extract. Liposomal batches of Aphanamixis polystachya leaf extract was prepared using design of experiment (DoE) and characterized using Malvern zetasizer, transmission electron microscopy (TEM), and FT-IR. Stability study of blank and leaf extract loaded liposome were performed in gastric media. In-vivo neurobehavioral and anti-inflammatory studies were performed on mice and rat model respectively. GC-MS data showed that major constituents of Aphanamixis polystachya leaf extract are 2-Pentanone, different acids (Octadec-9-enoic acid, 5-Hydroxypipeloic acid etc.), and Beta-Elemene etc. Malvern Zetasizer and TEM data showed that liposome batches of Aphanamixis polystachya leaf extract were in the range of 120 - 180 nm. Interactions between process parameters and material attributes found to have more impact on the average particle size and polydispersity of liposome batches compared to the impact of each parameter in isolation. Stability studies data suggest that blank and leaf extract loaded liposomes were stable at gastric conditions after 4 hours. In-vivo neurobehavioural study data indicated that significant improvement in the memory function, locomotor activity and ambulatory performance of dementia induced mice was observed for the liposomal batches compared to merely A. polystachya leaf extract.

Optimization, characterization and evaluation of liposomes from Malus hupehensis (Pamp.) Rehd. extracts.

The Malus hupehensis (Pamp.) Rehd. is a traditional medicine and edible plant. The previous study found that the extracts of M. hupehensis (Pamp.) Rehd. had a good antioxidant activity in vivo and in vitro. But its clinical application was limited by its poor solubility, rapidly metabolized and poor bioavailability. Hence, this article aimed at developing liposomes as a novel transdermal system for delivering M. hupehensis extracts efficiently. The prepared liposomes were characterized regarding their entrapment efficiency percentage (EE%), vesicle size (VS), polydispersity index (PDI), zeta potential (ZP) and drug loading (DL). Box-Behnken design response surface methodology and factorial design were used to optimize formulation and preparation process, respectively. The optimized liposomes had an EE of 77.29 ± 0.99%, VS of 102.74 ± 1.61 nm, ZP of -21.79 ± 1.43 mV, PDI of 0.291 ± 0.005 and DL was 6.68 ± 0.49%. Transmission electron microscopy showed liposomes had a regular spherical surface. In addition, liposomes exhibited superior skin permeation potential and retention capacity compared with solution. Histopathological study ensured the safety of liposome application. Meanwhile, the optimized liposome has a good stability. Hence, M. hupehensis extracts liposomes could be considered a promising vehicle for transdermal delivery.

Synergistic effects of liposomes encapsulating atorvastatin calcium and curcumin and targeting dysfunctional endothelial cells in reducing atherosclerosis.

BACKGROUND: Atherosclerosis is a major cardiovascular disease that causes ischemia of the heart, brain, or extremities, and can lead to infarction. The hypolipidemic agent atorvastatin calcium (Ato) alleviates atherosclerosis by reducing plasma lipid and inflammatory factors. However, the low bioavailability of Ato limits its widespread use and clinical effectiveness. Curcumin (Cur), a natural polyphenol with antioxidation and anti-inflammation bioactivities, has potential anti-atherosclerosis activity and may reduce Ato-induced cytotoxicity. MATERIALS AND METHODS: Liposomes modified using a targeting ligand (E-selectin-binding peptide) were prepared to co-deliver Ato and Cur to dysfunctional endothelial cells (ECs) overexpressing E-selectin. Molecules involved in the inhibition of adhesion (E-selectin and intercellular cell adhesion molecule-1 [ICAM-1]) and inflammation (IL-6 and monocyte chemotactic protein 1 [MCP-1]) in human aortic endothelial cells were evaluated using real-time quantitative PCR, flow cytometry, and immunofluorescence staining. The antiatherosclerosis effects of liposomes co-loaded with Ato and Cur in vivo were evaluated using ApoE knockout (ApoE-/-) mice. RESULTS: Targeted liposomes delivered Ato and Cur to dysfunctional ECs, resulting in synergistic suppression of adhesion molecules (E-selectin and ICAM-1) and plasma lipid levels. Moreover, this treatment reduced foam cell formation and the secretion of inflammatory factors (IL-6 and MCP-1) by blocking monocyte migration into the intima. In addition, Cur successfully reduced Ato-inducible cytotoxicity. CONCLUSION: Both in vitro and in vivo experiments demonstrated that cell-targeted co-delivery of Ato and Cur to dysfunctional ECs drastically reduces atherosclerotic lesions with fewer side effects than either Ato or Cur alone.

Calcium molybdate nanoparticles formation in egg phosphatidyl choline based liposome caused by liposome fusion.

In order to achieve the highly efficient 99mTc production from 100MoO3 by the 100Mo(n, 2n)99Mo reaction, we have developed a new protocol to synthesize nano-sized Mo particles, of which the size was controlled by the inner space of the liposomes. Calcium and molybdate ions were encapsulated into ∼100 nm size liposomes. The liposome suspensions were then mixed and heated to promote the membrane fusion. As a result, the insoluble CaMoO4 nanoparticles precipitated inside the liposomes. The median particle diameter of 168 nm and average diameter of 169 ±â€¯56 nm (n = 109) were obtained from an SEM image, and the particles have a powellite-structure. The formation process of the particles was then examined. The formation of nano-sized CaMoO4 was observed by the high resolution TEM image and TEM image of negative-stained liposome. At the room temperature, the fusion of liposome did not occur significantly. These results suggest that nanocrystals of the CaMoO4 were likely formed in the liposomes because of the liposome fusion and aggregated during the drying processes of reaction solution.

Nasal delivery of nanoliposome-encapsulated ferric ammonium citrate can increase the iron content of rat brain.

BACKGROUND: Iron deficiency in children can have significant neurological consequences, and iron supplementation is an effective treatment of choice. However, traditional routes of iron supplementation do not allow efficient iron delivery to the brain due to the presence of the blood-brain barrier. So an easily delivered iron formulation with high absorption efficiency potentially could find widespread application in iron deficient infants. RESULTS: In this study, we have developed and characterized a nanovesicular formulation of ferric ammonium citrate (ferric ammonium citrate nanoliposomes, FAC-LIP) and have shown that it can increase brain iron levels in rats following nasal administration. FAC was incorporated into liposomes with high efficiency (97%) and the liposomes were small (40 nm) and stable. Following intranasal delivery in rats, FAC-LIP significantly increased the iron content in the olfactory bulb, cerebral cortex, striatum, cerebellum and hippocampus, and was more efficient at doing so than FAC alone. No signs of apoptosis or abnormal cell morphology were observed in the brain following FAC-LIP administration, and there were no significant changes in the levels of SOD and MDA, except in the cerebellum and hippocampus. No obvious morphological changes were observed in lung epithelial cells or tracheal mucosa after nasal delivery, suggesting that the formulation was not overtly toxic. CONCLUSIONS: In this study, nanoscale FAC-LIP proved an effective system delivering iron to the brain, with high encapsulation efficiency and low toxicity in rats. Our studies provide the foundation for more detailed investigations into the applications of niosomal nasal delivery of liposomal formulations of iron as a simple and safe therapy for iron deficiency anemia. Graphical abstract The diagrammatic sketch of "Nasal delivery of nanoliposome-encapsulated ferric ammonium citrate can increase the iron content of rat brain". Nanoliposome-encapsulated ferric ammonium citrate (FAC-LIP) was successfully prepared and intranasal administration of FAC-LIP increased both the total iron contents and iron storage protein (FTL) expression in rat olfactory bulb, cerebral cortex, striatum and hippocampus, compared with those of FAC groups. Moreover, there was not overtly toxic affects to brain, lung epithelial cells and tracheal mucosa.

Cooperative antioxidative effects of zein hydrolysates with sage (Salvia officinalis) extract in a liposome system.

This study investigated the cooperative antioxidative effects of sage extract (SE) and zein hydrolysates (ZH). The combination of 3mg/ml ZH and 10µg/ml SE exhibited a significant synergism in inhibition of the formation of thiobarbituric acid-reactive substances and provided superior protection of liposomes against oxidation. Zeta-potential results revealed that the interactions between liposomes and ZH were electrostatic interactions. Particle size determination further proved that ZH and SE added to oxidized liposomes significantly decreased the mean particle size. Confocal laser scanning microscopy revealed that when ZH was present in the liposome oxidizing system, the droplet sizes were obviously decreased compared to oxidized samples. ZH dispersed more uniformly and the interfacial membrane was more compact in the ZH-SE liposome. Transmission electron microscopy conveyed that the ZH-SE complex around the liposome particles could form a denser network structure, preventing radicals and oxidants from the approach of the liposomes.

Target-controlled gating liposome "off-on" cascade amplification for sensitive and accurate detection of phospholipase D in breast cancer cells with a low-background signal.

Here we developed a simple, sensitive and accurate PLD detection method based on a target-controlled gating liposome (TCGL) "off-on" cascade amplified strategy and personal glucose meters (PGMs). It showed excellent sensitivity with a detection limit of 0.005 U L(-1) and well performed PLD activity analysis in breast cancer cells and inhibitor drug screening.

Formulation and evaluation of proniosomes containing lornoxicam.

Proniosomes are the new generation provesicular drug delivery system of non-ionic surfactant, lecithin and cholesterol which upon reconstitution get converted into niosomes. The objective of current study was to develop stable and sustain transdermal delivery system for lornoxicam. Lornoxicam-loaded topically applied proniosomal gel was formulated, optimized, and evaluated with the aim to deliver drug transdermally. Lornoxicam-loaded proniosomal gels were prepared that contained Lutrol F68 and lecithin as surfactants, cholesterol as a stabilizer, and minimal amount of ethanol and trace water. The resultant lornoxicam-loaded proniosomal gel were assessed for stability and the proniosomes-derived niosomes were characterized for morphology, size, zeta potential, and entrapment efficiency, which revealed that they were suitable for skin application. The coacervation phase separation technique was used in formulation of lornoxicam proniosomal gel and the gel was further assessed for in vitro permeation of lornoxicam through the freshly excised rat skin and the cumulative permeation amount of lornoxicam from proniosome, all exhibited significant increase as compared to 1.0 % lornoxicam-loaded pure gel. The optimized F5 batch had shown maximum entrapment efficiency up to 66.98 %. It has shown sustained drug release for more than 24 h. The skin permeability of proniosomal gel was found to be 59.73 %. The SEM and zeta potential studies showed formation of good and stable vesicles. Thus, proniosomes proved to have better potential for transdermal delivery of lornoxicam over conventional gel formulations.

Baicalin loaded in folate-PEG modified liposomes for enhanced stability and tumor targeting.

Bioavailability of baicalin (BAI), an example of traditional Chinese medicine, has been modified by loading into liposome. Several liposome systems of different composition i.e., lipid/cholesterol (L), long-circulating stealth liposome (L-PEG) and folate receptor (FR)-targeted liposome (L-FA) have been used as the drug carrier for BAI. The obtained liposomes were around 80 nm in diameter with proper zeta potentials about -25 mV and sufficient physical stability in 3 months. The entrapment efficiency and loading efficiency of BAI in the liposomes were 41.0-46.4% and 8.8-10.0%, respectively. The morphology details of BAI lipsosome systems i.e., formation of small unilamellar vesicles, have been determined by cryogenic transmission electron microscopy (cryo-TEM) and small angle X-ray scattering (SAXS). In vitro cytotoxicity of BAI liposomes against HeLa cells was evaluated by MTT assay. BAI loaded FR-targeted liposomes showed higher cytotoxicity and cellular uptake compared with non-targeted liposomes. The results suggested that L-FA-BAI could enhance anti-tumor efficiency and should be an effective FR-targeted carrier system for BAI delivery.

The Flocculating Cationic Polypetide from Moringa oleifera Seeds Damages Bacterial Cell Membranes by Causing Membrane Fusion.

A cationic protein isolated from the seeds of the Moringa oleifera tree has been extensively studied for use in water treatment in developing countries and has been proposed for use in antimicrobial and therapeutic applications. However, the molecular basis for the antimicrobial action of this peptide, Moringa oleifera cationic protein (MOCP), has not been previously elucidated. We demonstrate here that a dominant mechanism of MOCP antimicrobial activity is membrane fusion. We used a combination of cryogenic electron microscopy (cryo-EM) and fluorescence assays to observe and study the kinetics of fusion of membranes in liposomes representing model microbial cells. We also conducted cryo-EM experiments on E. coli cells where MOCP was seen to fuse the inner and outer membranes. Coarse-grained molecular dynamics simulations of membrane vesicles with MOCP molecules were used to elucidate steps in peptide adsorption, stalk formation, and fusion between membranes.

Potential of capsaicin-loaded transfersomes in arthritic rats.

In the present study, the biopotential of capsaicin (an active principle of capsicum) as a topical antiarthritic agent was studied in arthritic rats. Transfersomal vesicular system was employed for the topical administration of capsaicin in experimental rats. The characterization of prepared capsaicin-loaded transfersomes reveals their nano size (94 nm) with negative surface charge (-14.5 mV) and sufficient structural flexibility, which resulted in 60.34% entrapment efficacy, penetration across the biomembrane (220 µm) and 76.76% of drug release from vesicular system in 24 h in their intact form as evident from confocal laser scanning micrographic study. Results of transfersomal nanoformulation (capsaicin loaded, test) were compared with that of conventional gel formulation available in the market (Thermagel, standard), with an aim to assess the antiarthritic efficacy of our prepared capsaicin-loaded transfersomal formulation. In vivo antiarthritic activity study shows that our formulation possesses superior inhibitory activity than the marketed Thermagel formulation at the same dosage level, which could probably be due to the lesser permeability of Thermagel across the dermal barriers compared to our specially designed transfersomal delivery system. Moreover, the better tolerance of prepared vesicular formulation in biological system further enlightens the suitability of the transfersomal vesicle to be used as a novel carrier system for the topical administration of such highly irritant substance.

Properties of hybrid complexes composed of photosynthetic reaction centers from the purple bacterium Rhodobacter sphaeroides and quantum dots in lecithin liposomes.

Quantum dots (QDs) can absorb ultraviolet and long-wavelength light energy much more efficiently than natural light-harvesting proteins and transfer the excitation energy to photosynthetic reaction centers (RCs). Inclusion into liposomes of RC membrane pigment-protein complexes combined with QDs as antennae opens new opportunities for using such hybrid systems as a basis for artificial energy-transforming devices that potentially can operate with greater efficiency and stability than devices based only on biological components. RCs from Rhodobacter sphaeroides and QDs with fluorescence maximum at 530 nm (CdSe/ZnS with hydrophilic covering) were embedded in lecithin liposomes by extrusion of a solution of multilayer lipid vesicles through a polycarbonate membrane or by dialysis of lipids and proteins dispersed with excess detergent. The dimensions of the resulting hybrid systems were evaluated using dynamic light scattering and by transmission cryoelectron microscopy. The efficiency of RC and QD interaction within the liposomes was estimated using fluorescence excitation spectra of the photoactive bacteriochlorophyll of the RCs and by measuring the fluorescence decay kinetics of the QDs. The functional activity of the RCs in hybrid complexes was fully maintained, and their stability was even increased.

Lecithin-based nanostructured gels for skin delivery: an update on state of art and recent applications.

Conventional carriers for skin delivery encounter obstacles of drug leakage, scanty permeation and low entrapment efficiency. Phospholipid nanogels have recently been recognized as prominent delivery systems to circumvent such obstacles and impart easier application. The current review provides an overview on different types of lecithin nanostructured gels, with particular emphasis on liposomal versus microemulsion gelled systems. Liposomal gels investigated encompassed classic liposomal hydrogel, modified liposomal gels (e.g. Transferosomal, Ethosomal, Pro-liposomal and Phytosomal gels), Microgel in liposomes (M-i-L) and Vesicular phospholipid gel (VPG). Microemulsion gelled systems encompassed Lecithin microemulsion-based organogels (LMBGs), Pluronic lecithin organogels (PLOs) and Lecithin-stabilized microemulsion-based hydrogels. All systems were reviewed regarding matrix composition, state of art, characterization and updated applications. Different classes of lecithin nanogels exhibited crucial impact on transdermal delivery regarding drug permeation, drug loading and stability aspects. Future perspectives of this theme issue are discussed based on current laboratory studies.

Influence of lecithin-lipid composition on physico-chemical properties of nanoliposomes loaded with a hydrophobic molecule.

In this work, we studied the effect of nanoliposome composition based on phospholipids of docosahexaenoic acid (PL-DHA), salmon and soya lecithin, on physico-chemical characterization of vector. Cinnamic acid was encapsulated as a hydrophobic molecule in nanoliposomes made of three different lipid sources. The aim was to evaluate the influence of membrane lipid structure and composition on entrapment efficiency and membrane permeability of cinnamic acid. These properties are important for active molecule delivery. In addition, size, electrophoretic mobility, phase transition temperature, elasticity and membrane fluidity were measured before and after encapsulation. The results showed a correlation between the size of the nanoliposome and the entrapment. The entrapment efficiency of cinnamic acid was found to be the highest in liposomes prepared from salmon lecithin. The nanoliposomes composed of salmon lecithin presented higher capabilities as a carrier for cinnamic acid encapsulation. These vesicles also showed a high stability which in turn increases the membrane rigidity of nanoliposome as evaluated by their elastic properties, membrane fluidity and phase transition temperature.

Co-encapsulation of antioxidants into niosomal carriers: gastrointestinal release studies for nutraceutical applications.

Recently niosomes have been used as nutraceutical vehicles of functional components, useful in the prevention of many diseases caused by oxidative stress, with the aim to control their delivery into the body and to increase the nutritional quality of food dairy products with which these products can be enriched. We decided to develop novel niosomal formulations containing nutritional supplements such as gallic acid, ascorbic acid, curcumin and quercetin as single agents and in combination, to evaluate the effect of the active molecules co-encapsulation on the physico-chemical properties of the carriers, on their antioxidant properties and capability of releasing the encapsulated materials. Results suggest that the co-encapsulations of gallic acid/curcumin and ascorbic acid/quercetin mix influence their physico-chemical properties and their entrapment efficiencies respect to the formulations containing the single antioxidant; also the antioxidants releases appeared to improve and their combinations resulted in a promoted ability of reducing free radicals, due to a synergic antioxidant action.

Near-infrared light-sensitive liposomes for the enhanced photothermal tumor treatment by the combination with chemotherapy.

PURPOSE: To develop a near-infrared (NIR) light-sensitive liposome, which contains hollow gold nanospheres (HAuNS) and doxorubicin (DOX), and evaluate their potential utility for enhancing antitumor activity and controlling drug release. METHODS: The liposomes (DOX&HAuNS-TSL) were designed based on a thermal sensitive liposome (TSL) formulation, and hydrophobically modified HAuNS were attached onto the membrane of the liposomes. The behavior of DOX release from the liposomes was investigated by the dialysis, diffusion in agarose gel and cellular uptake of the drug. The biodistribution of DOX&HAuNS-TSL was assessed by i.v. injection in tumor-bearing nude mice. Antitumor efficacy was evaluated both histologically using excised tissue and intuitively by measuring the tumor size and weight. RESULTS: Rapid and repetitive DOX release from the liposomes (DOX&HAuNS-TSL), could be readily achieved upon NIR laser irradiation. The treatment of tumor cells with DOX&HAuNS-TSL followed by NIR laser irradiation showed significantly greater cytotoxicity than the treatment with DOX&HAuNS-TSL alone, DOX-TSL alone (chemotherapy alone) and HAuNS-TSL plus NIR laser irradiation (Photothermal ablation, PTA, alone). In vivo antitumor study indicated that the combination of simultaneous photothermal and chemotherapeutic effect mediated by DOX&HAuNS-TSL plus NIR laser presented a significantly higher antitumor efficacy than the PTA alone mediated by HAuNS-TSL plus NIR laser irradiation. CONCLUSIONS: Our study could be as the valuable reference and direction for the clinical application of PTA in tumor therapy.

Sustained broad-spectrum antibacterial effects of nanoliposomes loaded with silver nanoparticles.

BACKGROUND: The emergence of microbial resistance to antibiotics warrants the search for effective broad-spectrum antibacterial agents. Silver nanoparticles (AgNPs) have been used as antimicrobial agents. AgNPs encapsulated in nanolipososmes have been developed as effective antimicrobial agents. MATERIALS & METHODS: Nanoliposomes (<50 nm) were prepared using a modified reverse-phase evaporation method, and spherical, dextrose-capped AgNPs were synthesized. The prepared liposome AgNPs (LAgNPs) were characterized, and tested for their antibacterial effects. RESULTS: The size of LAgNPs is 25-80 nm. The release of AgNPs from nanoliposomes was sustained over 10 h. Complete growth inhibition of Eschericia coli, Salmonella enterica, Pseudomonas aeruginosa and Staphylococcus aureus was achieved using 180, 200, 160 and 120 µM, respectively, of LAgNPs. LAgNPs exhibited sustained broad-spectrum antibacterial effects compared with free AgNPs. CONCLUSION: Nanoliposomes loaded with AgNPs are potentially effective broad-spectrum antimicrobial agents. This new formula, which can be further fortified by encapsulation of additional established antibacterial agents, may be effective against antibiotic-resistant bacteria and also promote wound healing.