Biofabrication and optimization of silver nanoparticles using Campsis sp. to explore their antimicrobial properties

Plant mediated green synthesis of silver nanoparticles (AgNPs) holds promising applications in the field of Biomedicine, Food packaging and Wound healing. In the present investigation, biofabrication of AgNPs was performed using the aqueous extracts of Campsis sp. (Family Bignoniaceae) leaves and flowers growing in the premises of Kirori Mal College, University of Delhi, Delhi. Optimization of AgNPs was performed to analyse the varying effect of pH (6.0, 8.0, 10.0) and silver salt concentration (2mM, 4Mm and 6Mm) in controlling the shape and size of AgNPs which in turn governs their further applications. Interestingly, change in colour of the reaction mixture from pale yellow to reddish brown indicated the formation of AgNPs. These AgNPs were further characterized by UV-Visible spectroscopy and showed peak in the range of 400-450 nm which confirmed the synthesis of silver nanoparticles. Dynamic light scattering and zeta potential analysis (DLS-Zeta) confirmed the size of AgNPs around 200-300 nm. A significant zone of inhibition was observed for both Staphylococcus aureus (gram-positive) and Escherichia coli (gram-negative) bacterial strains which revealed the antimicrobial potential of Campsis sp. AgNPs. Therefore, Campsis AgNPs may provide a green, eco-sustainable alternate method for sustainable production of nanomaterials for biomedical applications. These AgNPs may also show tremendous applications in food packaging, wound healing and biomedical fields.

Physico-chemical characterization of traditionally prepared Yashada bhasma

Background: Yashada bhasma has been found to be very useful for the treatment of ailments like diabetes, eye disorder, urinary disorder etc. Since bhasma is a metallic preparation, so to prove its nontoxicity; modern standardization of the prepared samples is a must apart from other organoleptictests as mentioned in the ancient text.Objectives: The present study is aimed to synthesize bio-compatible Yashada bhasma from bioincompatible zinc metal. Further, comparative study of their chemical and physical properties throughsome quality control tests, physico-chemical tests and modern tests like XRD, DLS, Zeta potential, SEMand EDAX are carried out.Materials and methods: Yashada bhasma is prepared by a three step process i.e. Shodhan, Jarana andMarana. The inclusion of plant extracts and herbs during calcination process enhances its medicinalqualities, and reduces it to a nano size.Results: The XRD analysis of Yashada bhasma shows hexagonal ZnO crystalline phase whereas the rawmetal confirms the presence of crystallite Zinc metal. DLS shows reduction in particle size of YashadaBhasma (339.8 nm) as compared to raw metal (2063 nm) and this reduction is further supported by SEMwhich shows the particle size of Yashada bhasma (324 nm) and raw metal (1-2m). The zeta potential valueconfirms the stability of Yashada bhasma. EDAX revealed difference in concentration of Zinc and Oxygenin both the samples.Conclusion: An effort has been made to characterize the preparation of Yashada bhasma using sophisticated analytical tools as a step towards standardization of the bhasma. The results help in scientificallyestablishing the findings in line with the principle of Ayurveda.

PEG-PCL Nanocapsules Containing Curcumin: Validation of HPLC Method for Analyzing Drug-loading Efficiency, Stability Testing and Cytotoxicity on NIH-3T3 Cell Line

Abstract Curcumin (CUR) shows potential use for treating cancer. However, CUR has low solubility and reduced bioavailability, which limit its clinical effect. Therefore, the development of nanocarriers can overcome these problems and can ensure the desired pharmacological effect. In addition, it is mandatory to prove the quality, the efficacy, and the safety for a novel nanomedicine to be approved. In that sense, this paper aimed (a) to prepare CUR-loaded polyethylene glycol-poly(ε-caprolactone) nanocapsules; (b) to validate an analytical method by high performance liquid chromatography (HPLC) for quantifying CUR in these nanoformulations; (c) to evaluate the physicochemical stability of these formulations; and to investigate their cytotoxicity on NIH-3T3 mouse fibroblast cells. The HPLC method was specific to CUR in the loaded nanocapsules, linear (r = 0.9994) in a range of 10.0 to 90.0 µg.mL-1 with limits of detection and quantification of 0.160 and 0.480 µg.mL-1, respectively. Precision was demonstrated by a relative standard deviation lower than 5%. Suitable accuracy (102.37 ± 0.92%) was obtained. Values of pH, particle size, polydispersity index, and zeta potential presented no statistical difference (p > 0.05) for CUR-loaded nanoparticles. No cytotoxicity was observed against NIH-3T3 mouse embryo fibroblast cell line using both the tetrazolium salt and sulforhodamine B assays. In conclusion, a simple and inexpensive HPLC method was validated for the CUR quantification in the suspensions of nanocapsules. The obtained polymeric nanocapsules containing CUR showed suitable results for all the performed assays and can be further investigated as a feasible novel approach for cancer treatment.

Prescription design of raloxifene nanoemulsion / 中国药学杂志

OBJECTIVE:To study formulation design of raloxifene nanoemulsion. METHODS: The solubilities of raloxifene in excipients of nanoemulsion were investigated. On the basis, emulsifier and oil were selected by the emulsifying ability. The combination and optimum proportion among co-emulsifier, oil and emulsifier were determined by the pseudo-ternary phase diagram. The effect of raloxifene on nanoemulsion prescription was studied by drug loading. Finally chitosan and carboxylated chitosan were used to regulate the Zeta potential of raloxifene nanoemulsions. RESULTS: The optimum formulation ratio of LOA, IPP, RH40 and ethanol for loading 15 mg raloxifene is 0.167 g∶0.333 g∶0.3 g∶0.2 g, respectively. The Zeta potentials of the nanoemulsions can be changed by chitosan and carboxylated chitosan from -0.954 mV to 20 mV and -13 mV or so,respectively. The effect of different pH and dilution times on stability of formulations were slight. CONCLUSION: The formulations of raloxifene nanoemulsion including positive, negative and near zero Zeta potential were obtained, which have laid a foundation for absorption mechanism study of the raloxifene nanoemulsion.

Efficient immobilization of agarase using carboxyl-functionalized magnetic nanoparticles as support

Background: A simple and efficient strategy for agarase immobilization was developed with carboxyl-functionalized magnetic nanoparticles (CMNPs) as support. The CMNPs and immobilized agarase (agarase-CMNPs) were characterized by transmission electron microscopy, dynamic light scattering, vibrating sample magnetometry, scanning electron microscopy, X-ray diffraction, thermogravimetric analysis, and zeta-potential analysis. The hydrolyzed products were separated and detected by ESI-TOF-MS. Results: The agarase-CMNPs exhibited a regular spherical shape with a mean diameter of 12 nm, whereas their average size in the aqueous solution was 43.7 nm as measured by dynamic light scattering. These results indicated that agarase-CMNPs had water swelling properties. Saturation magnetizations were 44 and 29 emu/g for the carriers and agarase-CMNPs, respectively. Thus, the particles had superparamagnetic characteristics, and agarase was successfully immobilized onto the supports. Agaro-oligosaccharides were prepared with agar as substrate using agarase-CMNPs as biocatalyst. The catalytic activity of agarase-CMNPs was unchanged after six reuses. The ESI-TOF mass spectrogram showed that the major products hydrolyzed by agarase-CMNPs after six recycle uses were neoagarotetraose, neoagarohexaose, and neoagarooctaose. Meanwhile, the end-products after 90 min of enzymatic treatment by agarase-CMNPs were neoagarobiose and neoagarotetraose. Conclusions: The enhanced agarase properties upon immobilization suggested that CMNPs can be effective carriers for agarase immobilization. Agarase-CMNPs can be remarkably used in developing systems for repeated batch production of agar-derived oligosaccharides.

Adverse effect of beta-tricalcium phosphate with zeta potential control in repairing critical defects in rats' calvaria / Efeito adverso do beta-fosfato tricálcico com controle de potencial zeta no reparo de defeitos críticos em calvária de ratos

To evaluate whether a new biphasic cement composed of calcium sulfate and beta tricalcium phosphate with zeta potential control could induce or lead to bone neoformation in critical defects. METHODS: A critical defect of diameter 8 mm was made in the calvaria of forty male Wistar rats. In the Test Group (n = 20), the defects were filled with cement. In the Control Group (n = 20), the defect was not filled and only coagulum was present. The animals were sacrificed 7, 14, 21 and 42 days after the operation. Calvaria specimens were subjected to microtomography and were then prepared for histological analysis. The analyses included morphological assessment on the histopathology of the repair; comparative morphometric evaluation of the area of formation of bone trabeculae between the groups; and histochemical staining by means of tartrate-resistant phosphatase (TRAP) in order to identify osteoclasts. RESULTS: Microtomographic images of the defects filled by the cement did not show any decrease in area over the course of postoperative evolution. In the Test Group, the material continued to present a foreign-body response until the last observational periods. Histomorphological analysis showed that there were more significant groupings of giant cells in the Test Group and greater maturity of neoformed bone in the Control Group. Exogenous material was also present. Histomorphometric analysis showed that in the Control Group, the total area of bone neoformation was significantly greater (p = 0.009) and grew progressively. The giant cells presented a positive reaction to TRAP but no osteoclasts were observed. CONCLUSION: The ceramic cement did not induce or lead to bone neoformation from the microtomographic or histological point of view.

Avaliar se um novo cimento bifásico composto por sulfato de cálcio e beta fosfato tricálcico com controle de potencial zeta poderia induzir ou conduzir a neoformação óssea em defeitos críticos. MÉTODOS: Foi feito um defeito crítico de 8 mm de diâmetro na calvária de 40 ratos Wistar machos. No grupo teste (n = 20) os defeitos foram preenchidos pelo cimento. No grupo controle (n = 20) os defeitos não foram preenchidos, permaneceu apenas o coágulo. Os animais sofreram eutanásia em 7, 14, 21 e 42 dias do pós-operatório. Espécimes da calvária foram microtomografados e posteriormente preparados para análise histológica. As análises incluíram a avaliação morfológica da histopatologia do reparo e a avaliação morfométrica da área de formação das trabéculas ósseas comparativamente entre os grupos e coloração histoquímica por meio da fosfatase tartrato-resistente (TRAP) para identificação de osteoclastos. RESULTADOS: As imagens microtomográficas dos defeitos preenchidos pelo cimento não apresentaram diminuição da área de acordo com a progressão dos períodos pós-operatórios. No grupo teste houve permanência do material e resposta corpo estranho até os últimos períodos de observação. A histomorfologia mostrou agrupamentos mais expressivos de células gigantes no grupo teste e osso neoformado mais maduro no grupo controle e comprovou a presença de material exógeno. Na histomorfometria, a área total de neoformação óssea foi significativamente maior (p = 0,009) e crescente no grupo controle. As células gigantes apresentaram expressão histoquímica positiva para TRAP e não foram observados osteoclatos. CONCLUSÃO: O cimento cerâmico não induziu ou conduziu a neoformação óssea sob o ponto de vista microtomográfico e histológico.

Effects of Tussilago farfara by Grinding Dispersion Treatment on the Dispersion Stability of Xiao’er Feike Granules in Water / 中国药房

OBJECTIVE:To improve the dispersion stability in water of Tussilago farfara powder,and to improve compliance of Xiao’er feike granules. METHODS:The effects of 4 kinds of dispersion stabilizer (sodium hexametaphosphate, dextrin, PEG4000 and lecithin) on dispersion stability of suspension in water were investigated during the grinding of T. farfara using rate of absorbance change(β)and Zeta potential as index;IR spectrum of samples were characterized. Using original formulation with-out dispersion stabilizer as control,the dispersion stability of new formulation granules in water were analyzed comparatively after adding dispersion stabilizer. RESULTS:Among 4 kinds of dispersion stabilizer,β of sample prepared by sodium hexametaphos-phate was the lowest,while Zeta potential of it was the highest;compared with original T. farfara,β of T. farfara grinded with 2.5% sodium hexametaphosphate decreased by 16.8%,and Zeta potential absolute value increased by 29.4%;no new peak was found in IR spectrum. Compared with control granules,granules suspension prepared by new formulation had lower β and higher Zeta potential absolute value (P<0.01);particle size was 30 μm and no large particle aggregation was found;β was less than 5.0% within 20 s sedimentation. CONCLUSIONS:During the preparation of Xiao’er feike granules,the application of sodium hexametaphosphate in the grinding of T. farfara powder can improve the dispersion stability of granules in water and the compliance of the preparation.

Optimization of rutaecarpine solid lipid nanoparticles by central composite design and response surface methodology / 中草药

Objective: To optimize the prescription of rutaecarpine solid lipid nanoparticles (Rut-SLN). Methods: Using the film-ultrasound method to lining-up the Rut-SLN, with the entrapment efficiency (EE), Zeta potential, and the average particle size as the evaluation indexes, using central composite design to inspect the effects of glycerol monostearate/drug quality ratio (A), soybean lecithin for injection/glycerol monostearate mass ratio (B), Poloxamer 188 (C) on three factors of the EE, Zeta potential, and average particle size. Prediction and analysis for selecting the best prescription condition were carried out by using the response surface method. Results: According to the optimized prescription, the EE, Zeta potential, and the average particle size of Rut-SLN was respectively 84.27%, 122.6 nm, and -20.7 mV. Conclusion: The optimal prescription of Rut-SLN has better stability, feasibility, and high EE, which is suitable for the production.

Formulation and evaluation of nanoparticles containing artemisinin HCL.

The present study deals with the formulation and evaluation of Artemisinin HCl nanoparticles. Artemisinin is a sesquiterpene lactone chemical extract from Artemisia annua (sweet wormwood), is poorly soluble in water and a fast-acting blood schizonticide effective in treating the acute attack of malaria (including chloroquine – resistant and celebral malaria). Artemisinin are effective against multi-resistant strains of P. falciparum. The purpose of the present work is to minimize the dosing frequency, taste masking and toxicity and to improve the therapeutic efficacy by formulating Artemisinin HCl nanoparticles. Artemisinin HCl nanoparticles were formulated by solvent evaporation method using polymer poly(ε-caprolactone) with five different formulations. Nanoparticles were characterized by determining its particle size, polydispersity index, drug entrapment efficiency, particle morphological character and drug release. The particle size ranged between 100nm to 240nm. Drug entrapment efficacy was > 99%. The in-vitro release of nanoparticles were carried out which exhibited a sustained release of Artemisinin HCl from nanoparticles up to 24hrs. The results showed that nanoparticles can be a promising drug delivery system for sustained release of Artemisinin HCl.

Expression,purification and identification of I278T-mutant human cystathionine βsynthase / 国际检验医学杂志

Objective To investigate the expression and purification I278T-mutant human cystathionineβsynthase(CBS) in E . coli .Methods Site-directed mutagenesis by overlap extension using the polymerase chain reaction (PCR) was employed to construct mutant plasmids pGEX4T-1-CBS(I278T) ,which was induced and expressed in a medium containing 3% ethanol ,purified by affinity chromatography to obtain mutated CBS (I278T) protein .The activity ,UV-visible absorption spectroscopy ,protein particle size and Zeta potential of the purified protein were measured .Results Plasmid pGEX4T-1-CBS(I278T) was successfully constructed .The yield ,the specific activity and activity recovery of purified mutant CBS (I278T ) protein were 2 .3 mg/L ,21 .4 U/mg and 22 .6% .S-adenosylmethionine(AdoMet) with final concentration of 1 mmol/L showed no activation toward mutant CBS (I278T) protein .Ac-cording to UV-visible absorption spectroscopy analysis ,purified mutant CBS(I278T) had characteristic absorption peaks at 429 nm and 550 nm for heme-binding proteins .Protein average particle size was 7 .5 -10 .1 nm ,mainly in the form of tetramers ,and Zeta potential was - 16 .3 mV .Conclusion The methods of expression ,purification and identification of I278T-mutant human cystathionineβsynthase in E .coli were successfully established .

Physico-chemical and structural characterization of mucilage isolated from seeds of Diospyros melonoxylon Roxb

Mucilage was isolated from the seeds of Diospyros melonoxylon Roxb., a plant growing naturally in the forests of India. Various physico-chemical methods like particle analysis, scanning electron microscopy, differential scanning calorimetry, differential thermal analysis, thermogravimetry analysis, molecular weight by gel permeation chromatography, rheometry, elemental analysis, x-ray diffraction spectrometry, zeta potential, fourier transform infrared spectroscopy, 1D(1H and 13C) (NMR) have been employed to characterize this gum in the present study. Particle analyses suggest that mucilage had particle size in nanometer. SEM analysis suggested that the mucilage had irregular particle size. The glass transition temperature of the gum observed was 78 °C and 74 °C by DSC and DTA respectively. The Thermogravimetry analysis suggested that mucilage had good thermal stability with two stage decomposition. The molecular weight of mucilage was determined to be 8760, by gel permeation chromatography, while the viscosity of mucilage was observed to be 219.1 cP. The XRD pattern of the mucilage indicated a complete amorphous nature. Elemental analysis of the gum revealed specific contents of carbon, hydrogen, nitrogen and sulfur. The major functional groups identified from FT-IR spectrum include 3441 cm-1 (-OH), 1632 cm-1 (-COO-), 1414 cm-1 (-COO-) and 1219 cm-1 (-CH3CO). Analysis of mucilage by paper chromatography and 1D NMR indicated the presence of sugars.

Mucilagem foi isolada de sementes de Diospyros melanoxylon Roxb, uma planta que cresce naturalmente nas florestas da Índia. Vários métodos físico-químicos, como análise de partículas, microscopia electrônica, calorimetria diferencial de varredura, análise térmica diferencial, análise termogravimétrica, massa molecular por cromatografia de permeação em gel, viscosidade, análise elementar, espectrometria de difração de raios-x, potencial zeta, espectroscopia no infravermelho com transformada de Fourier, 1D (1H e 13C) (NMR) foram utilizados no presente estudo para caracterizar essa goma. A análise de partículas sugere que a mucilagem tem tamanho de partícula em nm. A análise SEM sugere que a mucilagem tem tamanho de partícula irregular. Observou-se temperatura de transição vítrea da goma de 78 °C e 74 °C por DSC e DTA, respectivamente. A análise termogravimétrica sugeriu que a mucilagem possuía boa estabilidade térmica, com duas fases de decomposição. A massa molecular da mucilagem foi 8760, por meio de cromatografia de permeação em gel, enquanto que a viscosidade foi 219,1 cP. O padrão de DRX da mucilagem indicou natureza completamente amorfa. Os principais grupos funcionais identificados a partir do espectro de FT-IR foram: 3441 cm-1 (-OH), 1632 cm-1 (-COO-), 1414 cm-1 (-COO-) e 1.219 cm-1 (CH3CO-). As análises de mucilagem por cromatografia em papel e 1D RMN indicaram a presença de açúcares.

Electrochemical attributes of soils influenced by sugarcane vinasse / Atributos eletroquímicos de solos influenciados pela vinhaça

The electrochemistry at the surface of colloidal particles in soils is related to important physical and chemical phenomena, such as flocculation and dispersion of soil particles, cation-exchange-capacity, anion adsorption, pesticides and heavy metals adsorption. Sorption of organic compounds on the surface of soil components may cause important changes on their electrochemical attributes. The vinasse has been applied in soils, mainly in sugarcane crops, as organic fertilizer. Its effects on physical, chemical and biological attributes of soils are well documented; however, little is known about the effects on electrochemical attributes. This work aimed to evaluate the effects of sugarcane vinasse on soil pH and zeta potential of the clay fraction of two Latosols (Oxisols) and an Argisol (Ultisol). The pH of soils amended with vinasse was measured in water and 1M KCl solution (ratio soil:water 1:2.5), and estimated the ∆pH (pH 1M KCl - pH in water). The zeta potential (ζ)) of the clay fraction was determined by electrophoretic mobility in 0,01M NaCl solution adjusted to different pH values (2, 3, 5, 6, 7, 9 and 11), and estimated the point of zero charge (PZC) (ζ) = 0). The soil pH and net charge of soils were clearly influenced by vinasse. These changes may influence important chemical and physical phenomena in soils and also help future studies involving vinasse in soils.

A eletroquímica das partículas coloidais do solo está relacionada com importantes fenômenos físicoquímicos, como floculação e dispersão do solo, capacidade de troca de cátions e ânions, adsorção de pesticidas e metais pesados. A sorção de compostos orgânicos na superfície dos componentes do solo pode causar importantes mudanças em seus atributos eletroquímicos. A vinhaça tem sido aplicada em solos, principalmente na cultura da cana-de-açúcar, como fertilizante orgânico. Embora os efeitos da vinhaça sobre atributos físicos, químicos e biológicos do solo sejam bem conhecidos, estudos envolvendo a eletroquímica das partículas do solo ainda são necessários. Objetivou-se com este trabalho avaliar o efeito da vinhaça sobre o pH e potencial zeta da fração argila de amostras de dois Latossolos e um Argissolo. Foi determinado o pH em água e em solução KCl 1M (relação solo:água 1:2,5) e estimado o pH (pH em KCl 1M ­ pH em água). Na fração argila foi determinado o potencial zeta () por mobilidade eletroforética em solução de NaCl 0,01M com diferentes valores de pH (2, 3, 5, 6, 7, 9 e 11) e estimado o ponto de carga zero (PCZ) ( = 0). O pH do solo e as cargas superficiais foram claramente influenciadas pela vinhaça. Essas mudanças podem influenciar importantes fenômenos físico-químicos do solo, bem como, servir de base para estudos futuros envolvendo vinhaça em solos.

Electrical properties of the red blood cell membrane and immunohematological investigation

Hemagglutination is widely used in transfusion medicine and depends on several factors including antigens, antibodies, electrical properties of red blood cells and the environment of the reaction. Intermolecular forces are involved in agglutination with cell clumping occurring when the aggregation force is greater than the force of repulsion. Repulsive force is generated by negative charges on the red blood cell surface that occur due to the presence of the carboxyl group of sialic acids in the cell membrane; these charges create a repulsive electric zeta potential between cells. In transfusion services, specific solutions are used to improve hemagglutination, including enzymes that reduce the negative charge of red blood cells, LISS which improves the binding of antibodies to antigens and macromolecules that decrease the distance between erythrocytes. The specificity and sensitivity of immunohematological reactions depend directly on the appropriate use of these solutions. Knowledge of the electrical properties of red blood cells and of the action of enhancement solutions can contribute to the immunohematology practice in transfusion services.

Effects of reprocessing techniques on function of polysulfone hemodialysis membranes / 上海第二医科大学学报

Objective To quantitatively compare the effects of bleach and peracetic acid reprocessing on the clearance and surface charge characteristics of Fresenius F80B polysulfone dialyzers. Methods Clearance experiments were performed using urea, vitamin B_12, and polydisperse dextrans in an in vitro dialysis circuit. Clearance, ultrafiltration coefficient and zeta potential were obtained on a new F80B dialyzer, after exposure to plasma in a 3 h in vitro dialysis session, and after cleaning with bleach and peracetic acid.Results Bleach was able to remove the protein deposit, restoring the clearance characteristics, but there was a significant increase in the net negative charge of the membrane due to chemical reaction with the bleach. In addition, longer time exposure to bleach altered the membrane transport characteristics, increasing the solute clearance. Dialyzers cleaned with peracetic acid had significantly lower clearance of the larger dextrans due to the presence of residual protein on or within the membrane. Conclusion Cleaning with bleach and peracetic acid may have dramatically different effects on the clearance and surface charge characteristics of F80B polysulfone dialyzers.

Preparation of Stable Solid Lipid Nanoparticles (SLNs) Suspension with Combined Surfactants / 中国药科大学学报

AIM:Surfactants and their blend play important roles in the preparation of solid lipid nanoparticles (SLNs).In this study,four types of surfactant were employed to investigate the influence of the surfactants on properties of SLNs in the absence of model drugs thereby avoiding the interaction between the surfactant and the drug.METHODS:The physicochemical properties of the colloidal systems,such as mean particle size,distribution range and Zeta potential,were investigated by laser diffractometry and the DSC analysis was performed as well.RESULTS:It was found that ionic surfactants,such as sodium deoxycholate, increased the Zeta potential of nanoparticles leading to improve the physical stability of the system.But it showed obviously relative low emulsification efficiency in the preparation.Non-ionic emulsifier,especially Pluronic F-68, offered additional steric stabilization effect avoiding aggregation of the fine particles in the colloidal system.CONCLUSION:The formulation in the study for the first time combined four types of additives including ionic surfactant (sodium deoxycholate),non-ionic emulsifier (Pluronic F-68 and Tween-80),and lecithin to obtain favorably stable nanosuspension,which could stabilize for more than six months without creaming.