Extraction, fractionation and physicochemical characterization of water-soluble polysaccharides from Artemisia sphaerocephala Krasch seed

The growing resistance of bacteria to current chemotherapy is a global concern that urgently requires new and effective antimicrobial agents, aimed at curing untreatable infection, reducing unacceptable healthcare costs and human mortality. Cationic polymers, that mimic antimicrobial cationic peptides, represent promising broad-spectrum agents, being less susceptible to develop resistance than low molecular weight antibiotics. We, thus, designed, and herein report, the synthesis and physicochemical characterization of a water-soluble cationic copolymer (P5), obtained by copolymerizing the laboratory-made monomer 4-ammoniumbuthylstyrene hydrochloride with di-methyl-acrylamide as uncharged diluent. The antibacterial activity of P5 was assessed against several multi-drug-resistant clinical isolates of both Gram-positive and Gram-negative species. Except for strains characterized by modifications of the membrane charge, most of the tested isolates were sensible to the new molecule. P5 showed remarkable antibacterial activity against several isolates of genera Enterococcus, Staphylococcus, Pseudomonas, Klebsiella, and against Escherichia coli, Acinetobacter baumannii and Stenotrophomonas maltophilia, displaying a minimum MIC value of 3.15 µM. In time-killing and turbidimetric studies, P5 displayed a rapid non-lytic bactericidal activity. Due to its water-solubility and wide bactericidal spectrum, P5 could represent a promising novel agent capable of overcoming severe infections sustained by bacteria resistant the presently available antibiotics.

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Physicochemical characterization of solid dispersion systems of tadalafil with poloxamer 407

Acta Pharmaceutica ◽

10.2478/v10007-009-0037-4 ◽

2009 ◽

Vol 59 (4) ◽

pp. 453-461 ◽

Cited By ~ 48

Author(s):

Vikrant Vyas ◽

Pankajkumar Sancheti ◽

Poonam Karekar ◽

Manali Shah ◽

Yogesh Pore

Keyword(s):

Solid Dispersion ◽

Binary Systems ◽

Physicochemical Characterization ◽

Water Soluble ◽

Poloxamer 407 ◽

Dissolution Enhancement ◽

Water Soluble Drug ◽

Dispersion Systems ◽

Rapid Dissolution

Physicochemical characterization of solid dispersion systems of tadalafil with poloxamer 407 Dissolution behaviour of a poorly water-soluble drug, tadalafil, from its solid dispersion systems with poloxamer 407 has been investigated. Solid dispersion systems of tadalafil were prepared with poloxamer 407 in 1:0.5, 1:1.5 and 1:2.5 ratios using the melting method. Characterization of binary systems with FTIR and XRPD studies demonstrated the presence of strong hydrogen bonding interactions, a significant decrease in crystallinity and the possibility of existence of amorphous entities of the drug. In the binary systems tested, 1:0.5 proportion of tadalafil/poloxamer 407 showed rapid dissolution of tadalafil (DE30 70.9 ± 3.6 %). In contrast, higher proportions of poloxamer 407 (1:1.5 and 1:2.5) offered no advantage towards dissolution enhancement of the drug, indicating altered rheological characteristics of the polymer at its higher concentration, which might have retarded the release rate of tadalafil.

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Tetra-2,3-pyrazinoporphyrazines with externally appended pyridine rings. 18. Physicochemical properties and photochemical behavior of new uncharged water soluble low-symmetry macrocycles [{Pd(OAc)2}3(PtCl2)LM] (M = MgII(H2O), ZNII, PdII)

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424617500250 ◽

2017 ◽

Vol 21 (04-06) ◽

pp. 334-344 ◽

Cited By ~ 3

Author(s):

Maria Pia Donzello ◽

Fabio Gigante ◽

Fabiola Sciscione ◽

Elisa Viola ◽

Karl M. Kadish

Keyword(s):

Physicochemical Characterization ◽

Water Soluble ◽

Experimental Conditions ◽

Visible Absorption ◽

New Class ◽

Enhanced Solubility ◽

Uv Visible ◽

Low Symmetry ◽

Visible Absorption Spectroscopy

The synthesis and physicochemical characterization of a new class of low-symmetry water soluble heteropentanuclear porphyrazine complexes are described. The investigated compounds, represented as [{Pd(OAc)[Formula: see text]}[Formula: see text](PtCl[Formula: see text]LM] •xH[Formula: see text]O where L [Formula: see text] tetrakis-2,3-[5,6-di(2-pyridyl)pyrazino]porphyrazinato dianion, M [Formula: see text] Mg[Formula: see text](H[Formula: see text]O), Zn[Formula: see text] or Pd[Formula: see text] and [Formula: see text] 3–8, were prepared under mild experimental conditions from the previously described heterobimetallic compounds [(PtCl[Formula: see text]LM]. Peripheral binding of one PtCl[Formula: see text]and three Pd(OAc)[Formula: see text]units in the new series of compounds occurs at the vicinal pyridine N atoms of each dipyridinopyrazine fragment via a “py–py” coordination. The newly synthesized porphyrazines were characterized by IR measurements in the solid state and UV-visible absorption spectroscopy in the polar nonaqueous solvents pyridine, dimethyl sulfoxide (DMSO) and dimethylformamide (DMF) as well as in water, the enhanced solubility in this medium being due to the presence of the external Pd(OAc)[Formula: see text] moieties. Data on the photosensitizing activity of the compounds for the generation of singlet oxygen, [Formula: see text]O[Formula: see text] were also obtained in DMF and should be of interest to researchers in the area of photodynamic therapy.

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CHARACTERIZATION OF DRUGS ENCAPSULATED INTO MESOPOROUS SILICA

International Journal of Applied Pharmaceutics ◽

10.22159/ijap.2019v11i6.35431 ◽

2019 ◽

pp. 7-11

Author(s):

ARIF BUDIMAN

Keyword(s):

Water Solubility ◽

Drug Loading ◽

Physicochemical Characterization ◽

Amorphous State ◽

Molecular State ◽

Water Soluble ◽

Crystal Nucleation ◽

Formulation Development ◽

Scanning Calorimetry

Solubility of the drug has a strong influence to achieve higher bioavailability of the drug in systemic circulation. More than 70% NCEs (new chemical entities) are hydrophobic, and practically difficult into solid formulation due to their poor water solubility. Mesoporous silicas (MSP) have been used for drug delivery system, especially for poorly water-soluble drugs. Encapsulation and interaction of drugs in MSP can enhance the delivery and maintain the stability of the drug. However, the characterization of the drug in MSP is necessary to confirm its molecular state. In this review, we present an overview of reports related to the characterization of drug encapsulated into MSP. Encapsulation of drugs in MSP can prevent recrystallization of drugs due to its inhibition of crystal nucleation. A porous material in MSP can maintain the drug in a physically stable amorphous state. The preventing of drug crystallization in MSP can enhance the solubility and the dissolution rate of drug. Therefore, in this work, attempts have been made to understand the molecular state of the drug in MSP. The physicochemical characterization of drug by transmission electron microscopy (TEM), scanning electron microscope (SEM), differential scanning calorimetry (DSC), fourier-transform infrared spectroscopy (FTIR), powder x-ray diffraction (PXRD) and thermogravimetric analysis (TGA) were discussed. The effect of solvent and methods of drug loading and the effect of the shape of MSP on release profiles are also presented. Overall, this review provides information about the characterization of drug encapsulated into MSP which will be useful in pharmaceutical formulation development.

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Physicochemical Characterization of a New Crystal Form and Improvements in the Pharmaceutical Properties of the Poorly Water-Soluble Antiosteoporosis Drug 3,9-bis(N,N-Dimethylcarbamoy-loxy)- 5H-benzofuro[3,2-c]quinoline-6-one (KCA-098) by Solid Dispersion with Hydroxypropylcellulose

Pharmaceutical Development and Technology ◽

10.1081/pdt-100102028 ◽

2000 ◽

Vol 5 (4) ◽

pp. 443-454 ◽

Cited By ~ 11

Author(s):

Tatsuhiko Yamada ◽

Noriyasu Saito ◽

Makoto Anraku ◽

Teruko Imai ◽

Masaki Otagiri

Keyword(s):

Solid Dispersion ◽

Physicochemical Characterization ◽

Crystal Form ◽

Water Soluble ◽

Poorly Water Soluble ◽

Pharmaceutical Properties

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Tetra-2,3-pyrazinoporphyrazines with externally appended pyridine rings. 16. A rare class of uncharged water soluble complexes: UV-vis spectral, redox, and photochemical properties

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424615500777 ◽

2015 ◽

Vol 19 (08) ◽

pp. 903-919 ◽

Cited By ~ 7

Author(s):

Maria Pia Donzello ◽

Daniela Vittori ◽

Elisa Viola ◽

Lihan Zeng ◽

Yan Cui ◽

...

Keyword(s):

Organic Solvents ◽

Physicochemical Characterization ◽

Water Soluble ◽

Spectral Studies ◽

Water Medium ◽

Experimental Conditions ◽

New Class ◽

Rare Class ◽

Uv Visible

The synthesis and physicochemical characterization of a new class of water soluble homo/heteropentanuclear porphyrazine complexes are described. The investigated compounds, prepared from the previously reported mononuclear species [ LM ]⋅x H 2 O (L = tetrakis-2,3-[5,6-di(2-pyridyl) pyrazino]porphyrazinato dianion; M = MgII ( H 2 O ), ZnII , CuII , CoII , PdII , PtII ; x = 3–8) in DMSO under mild experimental conditions, are represented as [{ Pd ( OAc )2}4 LM ]⋅x H 2 O (x = 11–22) and bear four Pd ( OAc )2 units, each externally coordinated at the vicinal pyridine N atoms of a single dipyridinopyrazine fragment of the porphyrazine macrocycle (py–py coordination). The newly synthesized compounds were examined by IR and magnetic susceptibility measurements in the solid state. Solution UV-visible spectral studies on all of the species were conducted in the low-donor organic solvents pyridine, dimethyl sulfoxide and dimethylformamide and in the water medium, whereas electrochemical measurements were performed in these media in the presence of tetrabutylammonium perchlorate (organic solvents) and KCl or NaOAc (water). Data on the photosensitizing activity for the generation of singlet oxygen, 1 O 2, of interest in photodynamic therapy, were also obtained in dimethylformammide solution on the compounds [{ Pd ( OAc )2}4 LM ]( M = MgII ( H 2 O ), ZnII , PdII , PtII ) and the measured ΦΔ values are presented and discussed. NMR spectral data on the complex [{ Pd ( OAc )2}4 LZn ] are also included and discussed.

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Orthogonal Optimization and Physicochemical Characterization of Water-Soluble Gelatin-Chitosan Nanoparticles with Encapsulated Alcohol-Soluble Eugenol

Food and Bioprocess Technology ◽

10.1007/s11947-020-02448-3 ◽

2020 ◽

Vol 13 (6) ◽

pp. 1024-1034

Author(s):

Qian Wang ◽

Li Zhang ◽

Wu Ding ◽

Dequan Zhang ◽

Kevin Reed ◽

...

Keyword(s):

Chitosan Nanoparticles ◽

Physicochemical Characterization ◽

Water Soluble ◽

Orthogonal Optimization

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Development of lipid nanocarriers for tuberculosis treatment: evaluation of suitable excipients and nanocarriers

Current Drug Delivery ◽

10.2174/1567201818666210212092112 ◽

2021 ◽

Vol 18 ◽

Author(s):

Gabriela Hädrich ◽

Cristiana Lima Dora ◽

Gustavo Richter Vaz ◽

Raphael Boschero ◽

Arthur Sperry Appel ◽

...

Keyword(s):

Drug Delivery ◽

Drug Delivery Systems ◽

Physicochemical Characterization ◽

Entrapment Efficiency ◽

Delivery Systems ◽

Water Soluble ◽

Scanning Calorimetry ◽

Lipid Nanocarriers ◽

Low Toxicity

Background: Lipid nanocarriers have been widely tested as drug delivery systems to treat diseases due to their bioavailability, controlled release, and low toxicity. For the pulmonary route, the Food and Drug Administration favors the use of substances generally recognized as safe, as well as biodegradable and biocompatible to minimize the possibility of toxicity. Tuberculosis (TB) remains a public health threat worldwide, mainly due to the long treatment duration and adverse effects. Therefore, new drug delivery systems to treat TB are needed. Objective: Physicochemical characterization of different lipid-based nanocarriers was used to optimize carrier properties. Optimized systems were incubated with Mycobacterium tuberculosis to assess whether lipid-based systems act as an energy source for the bacteria, which could be counterproductive to therapy. Method: Several excipients and surfactants were evaluated to prepare different types of nanocarriers using high-pressure homogenization. Results: A mixture of trimyristin with castor oil was chosen as the lipid matrix after differential scanning calorimetry analysis. A mixture of egg lecithin and PEG-660 stearate was selected as an optimal surfactant system as this mixture formed the most stable formulations. Three types of lipid nanocarriers, solid lipid nanoparticles, nanostructured lipid carriers (NLC), and Nano emulsions, were prepared, with the NLC systems showing the most suitable properties for further evaluation. It may provide the advantages of increasing the entrapment efficiency, drug release, and the ability to be lyophilized, producing powder for pulmonary administration being an alternative to entrap poor water-soluble molecules. Conclusion: Furthermore, the NLC system can be considered for use as a platform for the treatment of TB by the pulmonary route.

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