Purpose: To develop a safe, lipid-based non-viral gene delivery system that achieves high transfection efficiency in the presence of serum proteins. Methods: Polyplexes with the pAcGFP1-C1 plasmid were formed in phosphate buffered saline, pH 7.4 (PBS) using the novel poly[N-(2-hydroxypropyl)methacrylamide]-poly(N,N-dimethylaminoethylmethacrylate) diblock copolymer (pHPMA-b-pDMAEMA) at N/P=4. Cationic-Liposomes were prepared from a dried lipid film comprised of equimolar 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) and 1,2-dioleoyl-sn-glycero-3- phosphoethanolamine (DOPE). Lipopolyplexes were fabricated at lipid/DNA weight ratios up to 40. Particle size distribution and zeta potential of lipopolyplexes were determined by dynamic light scattering. HeLa cells viability in the presence and absence of lipopolyplexes was quantified using the CellTiter-Glo® luminescent assay. HeLa cell transfection efficiency in the presence and absence of FBS was visually assessed by confocal microscopy and quantitatively compared to the TurboFect™ control. Results: pHPMA-b-pDMAEMA exhibited a high condensation capacity of 1 µg of pDNA per 0.513 μg of polymer (N/P=1). Lipid-coating of polyplexes at lipid/DNA weight ratios up to 40 resulted in particle sizes +25 mV. Exposure to FBS significantly increased mean particle size to >300 nm, reduced zeta potential to -10 mV, and augmented polydispersity. Lipid coating of polyplexes only decreased HeLa cell viability at lipid/DNA ratios >20. HeLa transfection with lipopolyplexes was most effective at lipid/DNA = 20 and was significantly greater in the presence of FBS than measured for lipid-free polyplexes. Conclusion: Lipid coating of pHPMA-b-pDMAEMA/DNA polyplexes with an equimolar DOTAP/DOPE mixture at a lipid/DNA ratio = 20 effectively enhances in vitro transfection efficiency of HeLa cells in the presence of serum proteins.

Purpose: To develop a safe, lipid-based non-viral gene delivery system that achieves high transfection efficiency in the presence of serum proteins. Methods: Polyplexes with the pAcGFP1-C1 plasmid were formed in phosphate buffered saline, pH 7.4 (PBS) using the novel poly[N-(2-hydroxypropyl)methacrylamide]-poly(N,N-dimethylaminoethylmethacrylate) diblock copolymer (pHPMA-b-pDMAEMA) at N/P=4. Cationic-Liposomes were prepared from a dried lipid film comprised of equimolar 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) and 1,2-dioleoyl-sn-glycero-3- phosphoethanolamine (DOPE). Lipopolyplexes were fabricated at lipid/DNA weight ratios up to 40. Particle size distribution and zeta potential of lipopolyplexes were determined by dynamic light scattering. HeLa cells viability in the presence and absence of lipopolyplexes was quantified using the CellTiter-Glo® luminescent assay. HeLa cell transfection efficiency in the presence and absence of FBS was visually assessed by confocal microscopy and quantitatively compared to the TurboFect™ control. Results: pHPMA-b-pDMAEMA exhibited a high condensation capacity of 1 µg of pDNA per 0.513 μg of polymer (N/P=1). Lipid-coating of polyplexes at lipid/DNA weight ratios up to 40 resulted in particle sizes +25 mV. Exposure to FBS significantly increased mean particle size to >300 nm, reduced zeta potential to -10 mV, and augmented polydispersity. Lipid coating of polyplexes only decreased HeLa cell viability at lipid/DNA ratios >20. HeLa transfection with lipopolyplexes was most effective at lipid/DNA = 20 and was significantly greater in the presence of FBS than measured for lipid-free polyplexes. Conclusion: Lipid coating of pHPMA-b-pDMAEMA/DNA polyplexes with an equimolar DOTAP/DOPE mixture at a lipid/DNA ratio = 20 effectively enhances in vitro transfection efficiency of HeLa cells in the presence of serum proteins.

In view of the wide clinical use of theophylline, its narrow therapeutic index, repeated daily dosing and gastrointestinal side effects, sustained-release microcapsules of theophylline were prepared by a modified emulsion-solvent evaporation –non solvent addition technique. Two different polymers, namely, cellulose acetate butyrate (CAB) and ethyl cellulose (EC) were utilized at different polymer to drug ratios (2:1, 1:1 and 1:2). The microcapsules were evaluated in vitro for total recovery (yield %), microcapsule size (sieve analysis), surface morphology by scanning electron microscopy (SEM), drug loading (encapsulation efficiency) and drug release characteristics in simulated GIT fluids (pH 1.2 and 6.8). Results obtained revealed that spherical, free flowing microcapsules with smooth surfaces were successfully prepared with the two polymers. The percentages drug loading (encapsulation efficiency) were more than 95% for the two polymers at different polymer to drug ratios, indicating efficiency of the method. The drug release was affected by the type of polymer, polymer to drug ratios, microcapsule size and pH of the dissolution medium. The release of theophylline from CAB was slower than EC microcapsules. The release of theophylline from the microcapsules increased with decreasing microcapsules size. The release of theophylline from all the prepared microcapsules was markedly retarded as compared to commercial theophylline marketed product (Theo SR 100 Capsules). The release of theophylline from the prepared can be described by Zero-order release kinetic. These data clearly indicate ability of the prepared microcapsules to control and sustain the release of theophylline which is important for subsequent sustained absorption rate from GIT that can results in decreasing or eliminating gastrointestinal side effects as well as maintaining constant blood level for such drug with narrow therapeutics index, theophylline.

In view of the wide clinical use of theophylline, its narrow therapeutic index, repeated daily dosing and gastrointestinal side effects, sustained-release microcapsules of theophylline were prepared by a modified emulsion-solvent evaporation –non solvent addition technique. Two different polymers, namely, cellulose acetate butyrate (CAB) and ethyl cellulose (EC) were utilized at different polymer to drug ratios (2:1, 1:1 and 1:2). The microcapsules were evaluated in vitro for total recovery (yield %), microcapsule size (sieve analysis), surface morphology by scanning electron microscopy (SEM), drug loading (encapsulation efficiency) and drug release characteristics in simulated GIT fluids (pH 1.2 and 6.8). Results obtained revealed that spherical, free flowing microcapsules with smooth surfaces were successfully prepared with the two polymers. The percentages drug loading (encapsulation efficiency) were more than 95% for the two polymers at different polymer to drug ratios, indicating efficiency of the method. The drug release was affected by the type of polymer, polymer to drug ratios, microcapsule size and pH of the dissolution medium. The release of theophylline from CAB was slower than EC microcapsules. The release of theophylline from the microcapsules increased with decreasing microcapsules size. The release of theophylline from all the prepared microcapsules was markedly retarded as compared to commercial theophylline marketed product (Theo SR 100 Capsules). The release of theophylline from the prepared can be described by Zero-order release kinetic. These data clearly indicate ability of the prepared microcapsules to control and sustain the release of theophylline which is important for subsequent sustained absorption rate from GIT that can results in decreasing or eliminating gastrointestinal side effects as well as maintaining constant blood level for such drug with narrow therapeutics index, theophylline.

In view of the wide clinical use of theophylline, its narrow therapeutic index, repeated daily dosing and gastrointestinal side effects, sustained-release microcapsules of theophylline were prepared by a modified emulsion-solvent evaporation –non solvent addition technique. Two different polymers, namely, cellulose acetate butyrate (CAB) and ethyl cellulose (EC) were utilized at different polymer to drug ratios (2:1, 1:1 and 1:2). The microcapsules were evaluated in vitro for total recovery (yield %), microcapsule size (sieve analysis), surface morphology by scanning electron microscopy (SEM), drug loading (encapsulation efficiency) and drug release characteristics in simulated GIT fluids (pH 1.2 and 6.8). Results obtained revealed that spherical, free flowing microcapsules with smooth surfaces were successfully prepared with the two polymers. The percentages drug loading (encapsulation efficiency) were more than 95% for the two polymers at different polymer to drug ratios, indicating efficiency of the method. The drug release was affected by the type of polymer, polymer to drug ratios, microcapsule size and pH of the dissolution medium. The release of theophylline from CAB was slower than EC microcapsules. The release of theophylline from the microcapsules increased with decreasing microcapsules size. The release of theophylline from all the prepared microcapsules was markedly retarded as compared to commercial theophylline marketed product (Theo SR 100 Capsules). The release of theophylline from the prepared can be described by Zero-order release kinetic. These data clearly indicate ability of the prepared microcapsules to control and sustain the release of theophylline which is important for subsequent sustained absorption rate from GIT that can results in decreasing or eliminating gastrointestinal side effects as well as maintaining constant blood level for such drug with narrow therapeutics index, theophylline.

Botryodiplodia theobromae Pat. belongs to the endophytic fungi that live within the tissues of medicinal plants and produce bioactive natural products. The endophyte was isolated from the leaves of Dracaena draco L. The LC–MS-based metabolite fingerprinting of the ethyl acetate extract of B. theobromae with antibacterial activity led to the identification of 13 metabolites pertaining to various classes: dipeptides (maculosin and L,L-cyclo(leucylprolyl), alkaloid (norharman), coumarin and isocoumarins (bergapten, meranzin and monocerin), sesquiterpene (dihydrocumambrin A), aldehyde (formyl indanone), fatty alcohol (halaminol A) and fatty acid amide (palmitoleamide, palmitamide, capsi-amide and oleamide). This study reports for the first time, the LC–MS and LC–MS/MS identification of 13 known bioactive metabolites from the antibacterial ethyl acetate extract of B. theobromae isolated from the leaves of D. draco L.

Botryodiplodia theobromae Pat. belongs to the endophytic fungi that live within the tissues of medicinal plants and produce bioactive natural products. The endophyte was isolated from the leaves of Dracaena draco L. The LC–MS-based metabolite fingerprinting of the ethyl acetate extract of B. theobromae with antibacterial activity led to the identification of 13 metabolites pertaining to various classes: dipeptides (maculosin and L,L-cyclo(leucylprolyl), alkaloid (norharman), coumarin and isocoumarins (bergapten, meranzin and monocerin), sesquiterpene (dihydrocumambrin A), aldehyde (formyl indanone), fatty alcohol (halaminol A) and fatty acid amide (palmitoleamide, palmitamide, capsi-amide and oleamide). This study reports for the first time, the LC–MS and LC–MS/MS identification of 13 known bioactive metabolites from the antibacterial ethyl acetate extract of B. theobromae isolated from the leaves of D. draco L.

Medical diagnosis and therapy are essential for providing patients with proper care, although inefficient diagnosis and therapy are usually associated with either improper detection of the diseases, unsatisfactory therapeutic outcomes, and/or serious adverse reactions. Advances in the design of various diagnostic and therapeutic agents, and the recent trend of utilizing molecules for both therapeutic and diagnostic applications (i.e., theranostics), still have not achieved the maximum benefits of controlling the navigation and biodistribution of these molecules within the biological system.

The potential immunotoxicity of nanoparticles that are currently being approved, in different phases of clinical trials, or undergoing rigorous in vitro and in vivo characterizations in several laboratories has recently raised special attention. Products with no apparent in vitro or in vivo toxicity may still trigger various components of the immune system unintentionally and lead to serious adverse reactions. Cytokines are one of the useful biomarkers for predicting the effect of biotherapeutics on modulation of the immune system and for screening the immunotoxicity of nanoparticles both in vitro and in vivo, and they were recently found to partially predict the in vivo pharmacokinetics and biodistribution of nanomaterials. Control of polymer chemistry and supramolecular assembly provides a great opportunity for the construction of biocompatible nanoparticles for biomedical clinical applications. However, the sources of data collected regarding immunotoxicities of nanomaterials are diverse, and experiments are usually conducted using different assays under specific conditions. As a result, making direct comparisons nearly impossible, and thus, tailoring the properties of nanomaterials on the basis of the available data is challenging. In this Account, the effects of chemical structure, cross-linking, degradability, morphology, concentration, and surface chemistry on the immunotoxicity of an expansive array of polymeric nanomaterials will be highlighted, with a focus on assays conducted using the same in vitro and in vivo models and experimental conditions. Furthermore, numerical descriptive values have been utilized uniquely to stand for induction of cytokines by nanoparticles. This treatment of available data provides a simple way to compare the immunotoxicities of various nanomaterials, and the values were found to correlate well with published data. On the basis of the polymeric systems investigated in this study, valuable information has been collected that will aid in the future design of nanomaterials for biomedical applications, including the following: (a) the immunotoxicity of nanomaterials is concentration-and dose-dependent; (b) the synthesis of degradable nanoparticles is essential to decrease toxicity; (c) cross-linking minimizes the release of free polymeric chains and maintains high stability of the nanoparticles, thereby lowering their immunotoxicity; (d) lowering the amine density for cationic polymers that are being utilized for delivery of nucleic acids lowers the toxicity of the nanoparticles; (e) among neutral, zwitterionic, anionic, and cationic nanomaterials, neutral and cationic nanoparticles usually have the lowest and highest immunotoxicities, respectively; and (f) morphology, dimension, and surface chemistry have a great influence on the ability of nanomaterials to interact with the various components of the biological system and to modulate the immune system.

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