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Aim: In this study; it was aimed to examine the antibacterial activities and synergistic effects of curcumin, a phytotherapeutic agent, and gentamicin sulfate on bacteria. Materials and Methods: Antibacterial activity of different concentrations of curcumin and gentamicin sulfate on Klebsiella pneumoniae ATCC 13883, Pseudomonas aeruginosa ATCC 27853, Proteus vulgaris ATCC 3851, Bacillus cereus ATCC 11778, Enterococcus faecalis ATCC 29212, Listeria monocytogenes ATCC 7644 and Staphylococcus aureus ATCC 25923 minimal inhibitory concentration (MIC) and tested by disc diffusion methods. The synergistic effects of combinations of curcumin and gentamicin sulfate were examined by checkerboard test. Results: It was found that antibacterial activity was seen in all bacteria and the lowest MIC was 7.81 μg/mL in E. faecalis for curcumin and 0.08 μg/mL in K. pneumoniae for gentamicin sulfate. As a result of the disk diffusion test, inhibition zone diameters were detected at concentrations of 32 and 16 mg/mL in all bacteria tested. As a result of the checkerboard test, an additive effect was observed in four of the bacteria (P. vulgaris, B. cereus, L. monocytogenes, S. aureus) and a indifferent effect was observed in three of them (P. aeruginosa, K. pneumoniae, E. faecalis). The finding of the lowest fractional inhibitor concentration index (FICI=0.75) in B. cereus, one of the gram-positive bacteria, was interpreted as the combination of curcumin and gentamicin sulfate having a partial synergistic effect. Conclusion: This study is the first to evaluate the synergistic effect of curcumin and gentamicin sulfate. Antibacterial activity results suggest that curcumin can be used as an alternative agent in the treatment of bacterial infections. However, in order to clearly determine the effect of both the antibacterial activity of curcumin and its synergy with gentamicin sulfate during the treatment process, these results need to be supported by large-scale in vitro and in vivo studies that will include clinical isolates.

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Objective: To achieve rapid, quantitative and high-throughput detection of aminoglycoside antibiotic residues in pork. Methods: Square-array aligned SERS substrates based on Au nanoflowers （AuNFs） were prepared using PP synthetic paper as a substrate. Pork samples were pre-treated by QuEChERs method and subjected to SRES. Results: Using 4-mercaptobenzoic acid as the SERS probe molecule, the substrate exhibited good homogeneity, SERS enhancement effect, reproducibility and stability. the SERS signal intensities at the characteristic peaks at 475, 619 cm-1 showed good linear relationships with the logarithms of the concentrations of gentamicin sulphate and neomycin sulphate, respectively （R2 of 0.991 6 and 0.990 7, respectively）. The limits of detections （LODs） were as low as 1×10-9, 1×10-8 mol/L, respectively, and were successfully applied to the rapid, quantitative and high-throughput determination of aminoglycoside antibiotics in pork. Conclusion: The experimental method provides an economical, efficient, time-saving and highly sensitive way for the application of SERS technology for the detection of antibiotic residues in real meat samples.

Gentamicin sulfate is a broad-spectrum bactericidal aminoglycoside antibiotic produced by Micromonospora purpurea and used in clinical practice as an active substance containing a mixture of gentamicins C1 and C2. Gentamicin content is a standardised parameter controlled as part of a pharmaceutical product review. Currently, the quality control of the active substance gentamicin sulfate involves the use of high-performance liquid chromatography (HPLC) for the indirect identification of the component composition by comparison with a reference standard and for its quantification by calibration against the reference standard.The aim of the study was to develop a procedure for identifying and quantifying the components of the active substance gentamicin sulfate using nuclear magnetic resonance (NMR) spectroscopy that would not require reference standards.Materials and methods. The authors studied a sample of the active substance gentamicin sulfate using an Agilent DD2 NMR spectrometer operating at 600 MHz to record NMR spectra and an Agilent 1200 HPLC system equipped with a multiple wavelength detector (MWD) to obtain chromatograms.Results. Having determined the spectral properties of the C1, C1A, C2, C2A and C2B gentamicins comprising the active substance, the authors observed characteristic signals of the same type that corresponded to each of the gentamicins and did not overlap with other signals in the 1H and 13C spectra. These characteristic signals provided spectral markers indicative of the gentamicins of interest in the sample, with normalised integrated intensities equal to the mole fractions of the analytes. The authors compared NMR and HPLC measurements of the active substance composition.Conclusions. The authors developed a procedure for identifying and quantifying the constituents of the active substance gentamicin sulfate by 1H and 13C NMR spectroscopy, which requires less effort than HPLC procedures and no reference standards for the intended applications.

Background: Inverse psoriasis that is characterized by skinfold rash is seen in 12 to 36% of European patients with psoriasis. Isolated involvement of skinfolds can mimic a number of dermatoses with similar location. The differential diagnosis is increasingly frequently based on non-invasive methods, including dermatoscopy. Taking into account the warm and wet milieu of skinfolds, facilitating secondary infection, topical antibacterials and antiseptics are recommended for treatment, along with topical glucocorticosteroids and vitamin D3 analogues. Materials and methods: We have analyzed the results of assessment and treatment of 15 patients with psoriasis of major skinfolds that were admitted to the in-patient department of dermatology. All patients underwent dermatoscopy at 20 magnification. The patients were treated with desensitizing agents, hepatic protectors, and group B vitamins. Topical treatments applied in the rash areas included a combination topical agent containing mometasone furoate (0.5 mg), gentamicin sulfate (1 mg), econazole nitrate (10 mg), and dexpanthenol (50 mg). The treatment was considered effective if the M-PASI decreased at least by 75%; the results were assessed after 7 and 14 days of treatment. Results: In all cases, dermatoscopy of the vulgar psoriasis lesions showed vermilion or red to rosy background with evenly distributed dotted vessels and white scales diffusely located all over the visualized surface. The skinfold lesions were characterized by rosy or red background with evenly distributed dotted vessels, white scales located either as isolated groups, or at the periphery of the visualized areas; some plaques had local erosions, and in one case, hemorrhages. Morphological assessment of the biopsy samples in all patients with isolated skinfold lesions (n = 5) confirmed the diagnosis of psoriasis. Treatment-induced improvement was seen at day 2 to 3, and at day 14, there was a decrease of M-PASI by 90% in 6 (40%) patients and resolution of the lesions in 9 (60%). There were no treatment-associated adverse events or reactions. Conclusion: Dermatoscopy has proved to be a useful tool for non-invasive diagnostics of inverse psoriasis. At low magnification ( 20), its main sign was an even distribution of dotted vessels throughout the visualized area. In a number of cases, the dermatoscopic symptoms additionally included white scales grouped as isolated foci. The addition of the combination topical agent (mometasone furoate, gentamicin sulfate, econazole nitrate, and dexpanthenol) to the standard systemic therapy facilitated almost full resolution of skinfold psoriatic lesions.

The use of engineered semiconductor nanomaterials to address multi-drug resistance in bacteria has gained attention. In this study, an environmentally friendly cost-effective biological approach to synthesize copper sulfide nanoparticles (CuS-NPs) is reported. The CuS-NPs and the antibiotic Gentamicin Sulfate (GS) at the concentration of 40 μg/mL exhibit significant synergistic inhibition against several human pathogens (E. coli, Salmonella typhi, Klebsiella pneumoniae, Staphylococcus aureus, and Bacillus subtilis). The effective release of antibiotic and less frequent administration are therapeutic advantages. The drug entrapment and loading capacity of synthesized CuS nanoparticles (CuS-NP) were recorded as 61% and 39%, respectively. Additionally, a promising activity of the mycosynthesized CuS-NP is an increased cytotoxicity against MDA-MB-231 breast cancer cell line, as indicated by the estimated IC50 value.

Gentamicin sulfate (GNS) as an antibiotic drug is highly polar, non-volatile compound and lacks a UV absorbing chromophore and these properties pose an excessive challenge in the analysis of it for many years. Hence, it is urgent to progress a simple, rapid and low price method for quantification of GNS in medical, chemical and biological fields. This paper dedicated on the building of a novel and sensitive sensor for GNS detection that is created on the decoration of Ni(OH)2 onto nanozeolite NaX modified carbon paste electrode (Ni(OH)2–NaX/CPE). Initially, NaX was synthesized and characterized by numerous practices. Field emission scanning electron microscopy (FESEM) method demonstrated the existence of sphere-shaped nanozeolite NaX with diameter under 100 nm. Cyclic voltammetry investigations displayed that Ni(OH)2–NaX/CPE has impressively improved electro-catalytic oxidation of GNS versus Ni(OH)2/CPE because of mesoporous arrangement of nanozeolite NaX. The amounts of electron transfer coefficient, catalytic rate constant and diffusion coefficient of GNS were found to be 0.77, 1.77 × 104 cm3 mol− 1 s− 1 and 7.02 × 10− 6 cm2 s− 1, respectively. Also, the limits of detection and linear dynamic range were obtained to be 0.82 µM and 2.72–119.60 µM by differential pulse voltammetry method, respectively. The fabricated electrodes were effectively used for quantification of GNS in the pharmaceutical trainings with high accuracy and precision. [ABSTRACT FROM AUTHOR]

In this study, magnetic graphene oxide (MGO) nanohybrids were first prepared by loading Fe3O4 NPs onto graphene oxide (GO). Then, GS-MGO nanohybrids were prepared by grafting gentamicin sulfate (GS) onto MGO directly using a simple amidation reaction. The prepared GS-MGO had the same magnetism as MGO. They exhibited excellent antibacterial ability against Gram-negative bacteria and Gram-positive bacteria. The GS-MGO had excellent antibacterial performance against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Listeria monocytogenes (L. monocytogenes). When the addition concentration of GS-MGO was 1.25 mg/mL, the calculated bacteriostatic ratios against E. coli and S. aureus achieved 89.8% and 100%, respectively. For L. monocytogenes, only 0.05 mg/mL of GS-MGO had an antibacterial ratio as high as 99%. In addition, the prepared GS-MGO nanohybrids also exhibited excellent non-leaching activity with good recycling antibacterial ability. After eight times antibacterial tests, GS-MGO nanohybrids still exhibited an excellent inhibition effect on E. coli, S. aureus, and L. monocytogenes. Therefore, as a non-leaching antibacterial agent, the fabricated GS-MGO nanohybrid had dramatic antibacterial properties and also showed great recycling ability. Thus, it displayed great potential in the design of novel recycling antibacterial agents with non-leaching activity. [ABSTRACT FROM AUTHOR]

Hand eczema is a common multi-etiological disease manifested by evolutionary polymorphism of rashes. Hand eczema develops against the background of altered reactivity and genetic predisposition under the adverse effects of endogenous and exogenous factors. Hand eczema has a chronic course and is characterized by a wide range of clinical manifestations. The prevalence of eczematous lesions of the hands among the adult population is 1–2%, and among all skin diseases – 30–40%. The disease has an extremely negative impact on the quality of life, ability to work, career prospects and the social status of a person. The long course of eczematous lesions of the hands can be complicated by a secondary infection: bacterial and mycotic flora. Therefore, choosing the right and effective treatment for hand eczema is a particularly difficult task for a dermatologist. In recent years, a multicomponent drug based on gentamicin sulfate, dexpanthenol, mometasone furoate and econazole nitrate has been widely used for the treatment of hand eczema due to its high efficacy, tolerability, and safety. The use of this multicomponent drug in monotherapy for hand eczema is effective, leads to clinical remission and restoration of the quality of life of patients and is not accompanied by side effects and complications. This review focuses on the epidemiology, clinical features, and treatment options for hand eczema. Clinical experience with the use of a multicomponent drug in patients with hand eczema complicated by infection is also given.

Till nowadays microbiological assay is still widely used with several antibiotics that are composed of a mixture of related active compounds. However, obtaining a reasonably valid determination of the potency is dependent on the validity and the suitability of the assay design. The present work aimed to validate an assay design of an aminoglycoside antibiotic (Gentamicin Sulfate) using a two-dose Parallel Line Model agar diffusion assay in a large 8×8 rectangular plate. All preparatory procedures were done following United States Pharmacopeia and the Inhibition Zones were measured using a digital caliper to the nearest 0.01 mm. Analysis of variance of compendial requirements of regression and parallelism were found to be satisfactorily meeting the acceptance criteria. Specificity was achieved for the product under investigation with no detectable IZ that could be found for all components except the antibiotic. The validation method showed acceptable linearity of r2≥0.98. Accuracy and precision parameters showed RSD (%)

The use of engineered semiconductor nanomaterials to address multi-drug resistance in bacteria has gained attention. In this study, an environmentally friendly cost-effective biological approach to synthesize copper sulfide nanoparticles (CuS-NPs) is reported. The CuS-NPs and the antibiotic Gentamicin Sulfate (GS) at the concentration of 40 µg/mL exhibit significant synergistic inhibition against several human pathogens (E. coli, Salmonella typhi, Klebsiella pneumoniae, Staphylococcus aureus, and Bacillus subtilis). The effective release of antibiotic and less frequent administration are therapeutic advantages. The drug entrapment and loading capacity of synthesized CuS nanoparticles (CuS-NP) were recorded as 61% and 39%, respectively. Additionally, a promising activity of the mycosynthesized CuS-NP is an increased cytotoxicity against MDA-MB-231 breast cancer cell line, as indicated by the estimated IC50 value. [ABSTRACT FROM AUTHOR]

Targeted drug release is a significant research focus in the development of drug delivery systems and involves a biocompatible polymeric carrier and certain medicines. Cryostructuring is a suitable approach for the preparation of efficient macroporous carriers for such drug delivery systems. In the current study, the cryogenically structured carriers based on alginate/chondroitin sulfate mixtures were prepared and their physicochemical properties and their ability to absorb/release the bactericides were evaluated. The swelling parameters of the polysaccharide matrix, the amount of the tightly bound water in the polymer and the sulfur content were measured. In addition, FTIR and UV spectroscopy, optical and scanning microscopy, as well as a standard disk diffusion method for determining antibacterial activity were used. It was shown that alginate/chondroitin sulfate concentration and their ratios were significant factors influencing the swelling properties and the porosity of the resultant cryostructurates. It was demonstrated that the presence of chondroitin sulfate in the composition of a polymeric matrix slowed down the release of the aminoglycoside antibiotic gentamicin. In the case of the NH2-free bactericide, dioxidine, the release was almost independent of the presence of chondroitin sulfate. This trend was also registered for the antibacterial activity tests against the Escherichia coli bacteria, when examining the drug-loaded biopolymeric carriers. [ABSTRACT FROM AUTHOR]

Four three-dimensional rare earth metal – organic framework fluorescent sensor for efficient detection of gentamicin sulfate and Fe3+. [Display omitted] • Four MOFs were synthesized and the structures determined by single crystal x-ray diffraction. • Good water-dispersible and specific recognition ability for Gentamicin Sulfate and Fe3+. • Both MOFs have good selectivity and lower detection limits. Excessive use of gentamicin sulfate can cause severe nephrotoxicity and ototoxicity, abnormal levels of Fe3+ intake can also cause serious damage to body. Therefore, establishing a fast and accurate detection method for the above-mentioned substances is of great significance. However, traditional detection methods such as high-performance liquid chromatography still have certain problems such as high cost and complex operation. Fluorescent MOFs are favored by analysts due to their high specific surface area, high porosity, adjustable pore size, and good stability. In this paper, we have synthesized four rare earth MOFs based on the pyridinecarboxylic acid ligand (H 2 L), which are [Eu(L) 1/2 H 2 O] n , [Gd(L) 1/2 H 2 O] n , [Sm(L) 1/2 H 2 O] n , [Y(L) 3/2 H 2 O·DMF] n. The structures of four MOFs were confirmed by single crystal X-ray diffraction, which proved that MOF-1, MOF-2 and MOF-3 were isostructural, and all the four MOFs were three-dimensional structures. In the fluorescence test, gentamicin sulfate and Fe3+ can cause significant fluorescence quenching of MOF-1 and MOF-4 respectively, and show good selectivity and anti-interference performance, as well as low detection limit and wide detection range. This work may provide a possibility for the detection of gentamicin sulfate and iron ions in complex environments. [ABSTRACT FROM AUTHOR]

One way to effectively address endophyte infection and loosening is the creation of multifunctional coatings that combine anti-inflammatory, antibacterial, and vascularized osteogenesis. This study started with the preparation of strontium-doped titanium dioxide nanotubes (STN) on the titanium surface. Next, tannic acid (TA), gentamicin sulfate (GS), and pluronic F127 (PF127) were successfully loaded into the STN via layer-by-layer self-assembly, resulting in the STN@TA-GS/PF composite coatings. The findings demonstrated the excellent hydrophilicity and bioactivity of the STN@TA-GS/PF coating. STN@TA-GS/PF inhibited E. coli and S. aureus in vitro to a degree of roughly 80.95 % and 92.45 %, respectively. Cellular investigations revealed that on the STN@TA-GS/PF surface, the immune-system-related RAW264.7, the vasculogenic HUVEC, and the osteogenic MC3T3-E1 showed good adhesion and proliferation activities. STN@TA-GS/PF may influence RAW264.7 polarization toward the M2-type and encourage MC3T3-E1 differentiation toward osteogenesis at the molecular level. Meanwhile, the STN@TA-GS/PF coating achieved effective removal of ROS within HUVEC and significantly promoted angiogenesis. In both infected and non-infected bone defect models, the STN@TA-GS/PF material demonstrated strong anti-inflammatory, antibacterial, and vascularization-promoting osteogenesis properties. In addition, STN@TA-GS/PF had good hemocompatibility and biosafety. The three-step process used in this study to modify the titanium surface for several purposes gave rise to a novel concept for the clinical design of antimicrobial coatings with immunomodulatory properties. • The STN@TA-GS-PF coating had good cytocompatibility. • The STN@TA-GS-PF coating had good antimicrobial properties. • The STN@TA-GS-PF coating had good anti-inflammatory properties. • The STN@TA-GS-PF coating can be used for the repair of infected bone defects. [ABSTRACT FROM AUTHOR]

Over the past decade, much attention has been paid to chitosan as a potential drug carrier because of its non-toxicity, biocompatibility, biodegradability and antibacterial properties. The effect of various chitosan characteristics on its ability to carry different antibiotics is discussed in the literature. In this work, we evaluated the influence of the different molecular weights of this polymer on its potential as an antibacterial membrane after adding gentamicin (1% w/w). Three types of chitosan membranes without and with antibiotic were prepared using a solvent casting process. Their microstructures were analyzed with a 4K digital microscope, and their chemical bonds were studied using FTIR spectroscopy. Furthermore, cytocompatibility on human osteoblasts and fibroblasts as well as antibacterial activity against Staphylococcus aureus (S. aureus.) and Escherichia coli (E. coli) were assessed. We observed that the membrane prepared from medium-molecular-weight chitosan exhibited the highest contact angle (≈85°) and roughness (10.96 ± 0.21 µm) values, and its antibacterial activity was unfavorable. The maximum tensile strength and Young’s modulus of membranes improved and elongation decreased with an increase in the molecular weight of chitosan. Membranes prepared with high-molecular-weight chitosan possessed the best antibacterial activity, but mainly against S. aureus. For E. coli, is not advisable to add gentamicin to the chitosan membrane, or it is suggested to deplete its content. None of the fabricated membranes exhibited a full cytotoxic effect on osteoblastic and fibroblast cells. Based on our results, the most favorable membrane as a gentamicin carrier was obtained from high-molecular-weight chitosan.

In this study, magnetic graphene oxide (MGO) nanohybrids were first prepared by loading Fe3O4 NPs onto graphene oxide (GO). Then, GS-MGO nanohybrids were prepared by grafting gentamicin sulfate (GS) onto MGO directly using a simple amidation reaction. The prepared GS-MGO had the same magnetism as MGO. They exhibited excellent antibacterial ability against Gram-negative bacteria and Gram-positive bacteria. The GS-MGO had excellent antibacterial performance against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Listeria monocytogenes (L. monocytogenes). When the addition concentration of GS-MGO was 1.25 mg/mL, the calculated bacteriostatic ratios against E. coli and S. aureus achieved 89.8% and 100%, respectively. For L. monocytogenes, only 0.05 mg/mL of GS-MGO had an antibacterial ratio as high as 99%. In addition, the prepared GS-MGO nanohybrids also exhibited excellent non-leaching activity with good recycling antibacterial ability. After eight times antibacterial tests, GS-MGO nanohybrids still exhibited an excellent inhibition effect on E. coli, S. aureus, and L. monocytogenes. Therefore, as a non-leaching antibacterial agent, the fabricated GS-MGO nanohybrid had dramatic antibacterial properties and also showed great recycling ability. Thus, it displayed great potential in the design of novel recycling antibacterial agents with non-leaching activity.

With the objective of developing a localized gentamicin sulfate (GS) delivery system with a controlled release kinetics for the prevention/management of osteomyelitis, composite electrospun fibers composed of poly(lactic acid) (PLA) and poly(lactic-co-glycolic acid) (PLGA) blends and GS loaded mesoporous silica nanoparticles (npSiGS) were prepared (PLA/PLGA: 1:3, 1:1, 3:1 w/w). GS was loaded into silica nanoparticles by adsorption, using a concentrated GS solution, and npSiGS were dispersed in the polymer solutions and immobilized in the polymeric matrix by occlusion, during fibers formations. For comparison, non-composite fibers with the same blend compositions containing GS simply dispersed in the polymeric phase were also produced. GS loaded nanoparticles were characterized by nitrogen adsorption/desorption isotherms and GS loading was quantified by thermogravimetric analysis. The morphology of the electrospun fibers, assessed by SEM, revealed that npSiGS were embedded along the composite fibers, some in the form of small aggregates. In vitro release studies showed that composite fibers exhibited lower initial burst releases and slower release kinetics, dependent on blend composition. Composite fibers with PLGA as the major component (25PLA-npSiGS) had the fastest release kinetics, while fibers with equal amounts of both polymers (50PLA-npSiGS) or with PLGA as the minor component (75PLA-npSiGS) had slower release kinetics, with constant GS release rates after the first day. These results suggest that PLA/PLGA blend composition can be manipulated to obtain composite fibers with a controlled and tailored GS release for at least three weeks. Finally, the antibacterial effect against Staphylococcus aureus of all produced fibers containing GS was confirmed by a disk diffusion method. [ABSTRACT FROM AUTHOR]

The current study describes the elaboration of a hybrid drug delivery platform for an intravesical application based on curcumin/gentamicin sulfate simultaneously loaded niosomes incorporated into thermosensitive in situ gels. Series of niosomes were elaborated via the thin film hydration method, evaluating the impact of non-ionic surfactants', cholesterol's, and curcumin's concentration. The formulation composed of equimolar ratio of Span 60, Tween 60, and 30 mol% cholesterol was selected as the optimal composition, due to the high entrapment efficiency values obtained for both drugs, and appropriate physicochemical parameters (morphology, size, PDI, and zeta potential), therefore, was further incorporated into Poloxamers (407/188) and Poloxamers and chitosan based in situ gels. The developed hybrid systems were characterized with sol to gel transition in the physiological range, suitable rheological and gelling characteristics. In addition, the formed gel structure at physiological temperatures determines the retarded dissolution of both drugs (vs. niosomal suspension) and sustained release profile. The conducted microbial studies of selected niosomal in situ gels revealed the occurrence of a synergetic effect of the two compounds when simultaneously loaded. The findings indicate that the elaborated thermosensitive niosomal in situ gels can be considered as a feasible platform for intravesical drug delivery. [ABSTRACT FROM AUTHOR]

This experiment was to study the therapeutic effect of modified Yujin powder on E. coli in the P. przewalskii. Twenty the Procapra przewalskii with the E. coli were selected from the Wildlife Rescue Center of the Qinghai Lake National Nature Reserve and randomly divided into low-dose group, highdose group, gentamicin sulfate group and control group with 5 Procapra przewalskii in each group. The P. przewalskii in modified Yujin powder group were given Yujing powder once every morning and evening, 3, 4 mL/(kg-BW) for the low-dose group and high-dose group, respectively. The P. przewalskii were injected with gentamicin sulfate intramuscularly, once every morning and evening. The P. przewalskii in control group were fed normally and no medicine was given. After 7 d, the clinical symptoms of the P. przewalskii were observed, and the blood routine, serum biochemical parameter, serum immune and antioxidant indices were measured. The results showed that the P. przewalskii were sensitive reaction, increased appetite, and no diarrhea in the modified Yujin powder group. The healing rates were 75%, 85%, and 60% in low-dose group, high-dose group, gentamicin sulfate group, respectively. The effects of modified Yujin powder was better than gentamicin sulfate. The contents of blood urea nitrogen (BUN), malondialdehyde (MDA), and the number of white blood cell (WBC) in 3 drug delivery groups were extremely significantly lower (P<0.01) than the control group, and the contents of potassium (K), total protein (TP), albumin (ALB), globulin (GLB), and total antioxidant capacity (T-AOC) in the 3 drug delivery groups were extremely significantly higher (P<0.01) than that of control group, but there were no remarkable differences between the 3 drug delivery groups. The serum catalase (CAT) activity in the high-dose group was extremely significantly higher (P<0.01) than that in the low-dose group, gentamicin sulfate group, and control group. Consequently, modified Yujin powder had a good therapeutic effect on the E. coli in P. przewalskii. and the effect of the high-dose group was better. [ABSTRACT FROM AUTHOR]

Bacterial infection is among the most common diseases that threaten human health. Antibiotics are effective in treating bacterial infections. However, the overuse of antibiotics will lead to an increase in bacterial resistance. To reduce the overuse of antibiotics and improve the effective use of antibiotics through slow release, silk fibroin (SF)/polyethylene oxide (PEO) nanofiber membranes with different SF and PEO proportions were prepared by electrospinning. The ecofriendly solvent ethanol solution was used for electrospinning for better protection of antibiotic activity. The SEM showed that the surface of SF/PEO (2:8) and SF/PEO (3:7) was smoother and more uniform. With the increase of SF content, the thermal stability and hydrophilicity of SF/PEO nanofiber membranes were improved. The SF/PEO (3:7) nanofiber membrane had the best mechanical property and its maximum stress and strain were 4.6 1 ± 0.24 MPa and 16.36 ± 0.41%, respectively. Based on these good properties, SF/PEO (3:7) nanofiber membrane was chosen for loading and releasing gentamicin sulfate (GS). The fabricated (GS)/SF/PEO (3:7) nanofiber membrane exhibited good release efficiency and showed the good antibacterial activity against Staphylococcus aureus and Escherichia coli. These investigations indicated the GS/SF/PEO (3:7) nanofiber membrane (GS/SF/PEO) has a great potential for application in antibacterial materials. [ABSTRACT FROM AUTHOR]

Over the past decade, dermatological practice has seen an increase in the number of patients suffering from skin and subcutaneous tissue diseases. Annually, 6.4-6.9 million new cases of this group of diseases are registered, which encourages the constant search for new drugs and the continuous improvement of methods and schemes of application of proven drugs. Topical corticosteroids, despite more than 65 years of history of use in the treatment of patients with steroid-sensitive dermatoses, have not lost their relevance. At present, they have no therapeutic alternative in terms of speed of onset and anti-inflammatory activity, so they are essential in the treatment of many skin pathologies. One of the trends in modern pharmacology is not so much the production of new active molecules of TCS or their modifications, as the creation of new pharmacological forms of known molecules - micronized, nanonized, which give the drug the most important property -increased bioavailability. This advanced technology is actively used in the production of domestic topical drugs of Akriderm lines, which make a major contribution to the program of import substitution and drug availability for the population. The optimal combination of ingredients of the foundation of these drugs complements and potentiates the therapeutic effect of steroid. For more than 30 years in clinical practice, a combination of 0.05% betamethasone dipropionate, 0.1% gentamicin sulfate and 1% clotrimazole (Triderm, Akriderm GK) is used. Many years of positive clinical experience of dermatologists using this fixed combination proves the validity of its use in many clinical situations when bacterial and fungal infection is involved. An open randomized comparative study conducted by Russian dermatologists on the efficacy and safety of Akriderm GK (cream) and Triderm (cream) in the complex treatment of eczema showed similar profiles of high clinical efficacy and safety of both drugs.

The densities of three pharmacologically significantly used drugs i.e., Chloroquine phosphate (CP), Acefylline piperazine (AP) and Gentamicin sulfate (GS) have been carried out in aqueous (aq), aqueous polyethylene glycol (aq-PEG) and aqueous polyvinyl pyrrolidone (aq-PVP) solvent systems within concentration range (0.02–0.1 ± 0.001 mol.dm−3) at different temperatures (293.15–318.15 K) with the interval of 5 K. Density data were used to evaluate volumetric properties of drugs (CP, AP and GS) by apparent molar volume, partial molar volumes, molar expansibilities and isothermal expansion coefficient. ϕE° provides information about the absence or presence of a caging or packing effect. Partial molar transfer volume was also calculated to study the hydrophilic/hydrophobic interactions in aq-PEG and aq-PVP solvent systems. The results are interpreted in terms of drug–solvent and drug-drug interactions and structure making or breaking abilities of drugs in aq, aq-PEG and aq-PVP solvent systems.

The development of new antibacterial agents that can efficiently eradicate biofilms is of crucial importance to combat persistent and chronic bacterial infections. Herein, the fabrication of photoresponsive vesicles capable of the sequential release of nitric oxide (NO) and gentamicin sulfate (GS) is reported, which can not only efficiently disperse Pseudomonas aeruginosa (P. aeruginosa) PAO1 biofilm but also kill the planktonic bacteria. Well‐defined amphiphilic diblockcopolymers of poly(ethylene oxide)‐b‐poly(4‐((2‐nitrobenzyl)(nitroso)amino)benzyl methacrylate) (PNO) is first synthesized through atom transfer radical polymerization (ATRP). The PNO diblock copolymer self‐assembled into vesicles in aqueous solution, and a hydrophilic antibiotic of GS is subsequently encapsulated into the aqueous lumens of vesicles. The vesicles undergo visible light‐mediated N‐NO cleavage, releasing NO and disintegrating the vesicles with the release of the GS payload. The sequential release of NO and GS efficiently eradicate P. aeruginosa PAO1 biofilm and kill the liberated bacteria, showing a better antibiofilm effect than that of NO or GS alone. [ABSTRACT FROM AUTHOR]

Antibiotics are designed to treat bacterial infections in humans and animals; however, the overuse of various antibiotics and consequent contamination in the environment can have adverse effects on aquatic, soil, and saprophytic organisms. The house fly, an important decomposer in ecosystems, has been used for bioconversion of human and animal waste. Vermireactors have been used to remove antibiotics from waste for pollution control, but the effects of antibiotics on fly larvae are unclear. In the present work, we aimed to reveal the mechanism underlying the effects of antibiotics on larval growth in house flies at the transcriptome and microbiome levels and the relationships between genes and the microbiota. Observation of house flies after antibiotic exposure showed that gentamicin sulfate and levofloxacin hydrochloride inhibited larval development to a greater extent than amoxicillin. Transcriptome analysis revealed that biological pathways related to protein synthesis and the metabolism of fatty acids, pentose, and glucuronate were significantly enriched in flies exposed to gentamicin sulfate and levofloxacin hydrochloride. Crucial genes in these pathways were identified as candidates for future study. Microbiome analysis revealed three key bacteria that were closely correlated with gentamicin sulfate and levofloxacin hydrochloride exposure. The correlation network between the differentially expressed genes and bacteria identified an important microbic effector, Pseudomonas and its associated genes. This work will improve the knowledge about the mechanism underlying the effects of antibiotics on the larval development of house flies in the environment and provide guidance for improving the application of house fly bioconversion.

This paper aimed to study the effect of aqueous, aqueous polyethylene glycol (1.0 %w/v) and aqueous polyvinyl pyrrolidone (1.0 %w/v) on the physicochemical behaviour of three pharmaceuticals substantial drugs by viscosity method. Viscosity measurements of the drugs (chloroquine phosphate, acefylline piperazine and gentamicin sulfate) solutions were performed within concentration ranges from 2.0 × 10−2 to 10.0 × 10−2 ± 0.001 mol.dm−3 at varying temperatures (293.15, 298.15, 303.15, 308.15, 313.15 and 318.15 ± 0.01 K). The viscosity data used to interpret the interactions (drug-drug and drug-solvent) existing in the solutions of drugs in terms of ‘A’ and ‘B’ coefficients of Jones–Dole equation respectively. Temperature derivatives of the B-coefficient (dB/dT) were also calculated which help to establish the relation between the nature of the solute and the structural modifications in the solution. Hence, the structure promoting ability of the AP in aqueous system and structure destroying effect of CP, AP and GS in the aqueous-polymeric system was observed. The FTIR studies of CP, AP and GS show that the chemical identity of the drug was not affected by the polymers and no binding of the new forming compound was detected.

Purpose: Direct delivery of aminoglycosides to the lungs was under extensive evaluations during the last decades. Because of large particle size, low density and porous structure, large porous particles (LPPs) are versatile carriers for this purpose. In this study, poly (lactic-co-glycolic acid) (PLGA) LPPs encapsulating gentamicin sulfate were prepared and in vitro characteristics of their freeze-dried powder as a dry powder inhaler (DPI) were evaluated. Methods: To prepare PLGA LPPs, a double emulsification-solvent evaporation method was optimized and gentamicin sulfate was post-loaded in the LPPs. In vitro characteristics including morphological features, thermal behavior, aerodynamic profile and cumulative drug release were evaluated by the scanning electron microscope (SEM), differential scanning calorimetry (DSC), next-generation cascade impactor (NGI) and Franz diffusion cell respectively. Results: The obtained results revealed that the preparation method was capable to produce spherical large homogenous highly porous particles. 94% of gentamicin sulfate released from LPPs up to 30 minutes. Mass median aerodynamic diameter (MMAD) and fine particle fraction (FPF) were 4.9 µm and 39% respectively. Conclusion: In this study, dry powder formulation composed of PLGA LPPs encapsulating gentamicin sulfate showed a promising in vitro behavior as a pulmonary delivery carrier. Improvements on the aerodynamic behavior and in vivo evaluations recommended for further developments.

Abstract Background Magnetosomes (also called bacterial magnetic nanoparticles; BMPs) are biomembrane-coated nanoparticles synthesized by magnetotactic bacteria (MTB). Engineered BMPs fused to protein A (termed ∆F-BMP-FA) bind antibodies (Abs) automatically, and thus provide a series of potential advantages. However, no report so far has systematically evaluated functional applicability of genetically engineered BMPs. Results We evaluated properties of ∆F-BMP-FA, and developed/optimized culture methods for host strain Magnetospirillum gryphiswaldense ΔF-FA, ∆F-BMP-FA extraction conditions, conditions for Ab conjugation to ∆F-BMP-FA surface, and procedures for antigen detection using ∆F-BMP-FA/Ab complexes (termed BMP-A-Ab). Fed-batch culture for 36 h in a 42-L fermentor resulted in yields (dry weight) of 2.26 g/L for strain ΔF-FA and 62 mg/L for ∆F-BMP-FA. Optimal wash cycle number for ∆F-BMP-FA purification was seven, with magnetic separation following each ultrasonication step. Fusion of protein A to BMPs resulted in ordered arrangement of Abs on BMP surface. Linkage rate 962 μg Ab per mg ∆F-BMP-FA was achieved. BMP-A-Ab were tested for detection of pathogen (Vibrio parahaemolyticus; Vp) surface antigen and hapten (gentamicin sulfate). Maximal Vp capture rate for BMP-A-Ab was 90% (higher than rate for commercial immunomagnetic beads), and detection sensitivity was 5 CFU/mL. ∆F-BMP-FA also bound Abs from crude mouse ascites to form complex. Lowest gentamicin sulfate detection line for BMP-A-Ab was 0.01 ng/mL, 400-fold lower than that for double Ab sandwich ELISA, and gentamicin sulfate recovery rate for BMP-A-Ab was 93.2%. Conclusion Our findings indicate that engineered BMPs such as ∆F-BMP-FA are inexpensive, eco-friendly alternatives to commercial immunomagnetic beads for detection or diagnostic immunoassays, and have high Ab-conjugation and antigen-adsorption capacity.

Targeted drug release is a significant research focus in the development of drug delivery systems and involves a biocompatible polymeric carrier and certain medicines. Cryostructuring is a suitable approach for the preparation of efficient macroporous carriers for such drug delivery systems. In the current study, the cryogenically structured carriers based on alginate/chondroitin sulfate mixtures were prepared and their physicochemical properties and their ability to absorb/release the bactericides were evaluated. The swelling parameters of the polysaccharide matrix, the amount of the tightly bound water in the polymer and the sulfur content were measured. In addition, FTIR and UV spectroscopy, optical and scanning microscopy, as well as a standard disk diffusion method for determining antibacterial activity were used. It was shown that alginate/chondroitin sulfate concentration and their ratios were significant factors influencing the swelling properties and the porosity of the resultant cryostructurates. It was demonstrated that the presence of chondroitin sulfate in the composition of a polymeric matrix slowed down the release of the aminoglycoside antibiotic gentamicin. In the case of the NH2-free bactericide, dioxidine, the release was almost independent of the presence of chondroitin sulfate. This trend was also registered for the antibacterial activity tests against the Escherichia coli bacteria, when examining the drug-loaded biopolymeric carriers.

The current study describes the elaboration of a hybrid drug delivery platform for an intravesical application based on curcumin/gentamicin sulfate simultaneously loaded niosomes incorporated into thermosensitive in situ gels. Series of niosomes were elaborated via the thin film hydration method, evaluating the impact of non-ionic surfactants’, cholesterol’s, and curcumin’s concentration. The formulation composed of equimolar ratio of Span 60, Tween 60, and 30 mol% cholesterol was selected as the optimal composition, due to the high entrapment efficiency values obtained for both drugs, and appropriate physicochemical parameters (morphology, size, PDI, and zeta potential), therefore, was further incorporated into Poloxamers (407/188) and Poloxamers and chitosan based in situ gels. The developed hybrid systems were characterized with sol to gel transition in the physiological range, suitable rheological and gelling characteristics. In addition, the formed gel structure at physiological temperatures determines the retarded dissolution of both drugs (vs. niosomal suspension) and sustained release profile. The conducted microbial studies of selected niosomal in situ gels revealed the occurrence of a synergetic effect of the two compounds when simultaneously loaded. The findings indicate that the elaborated thermosensitive niosomal in situ gels can be considered as a feasible platform for intravesical drug delivery.

The densities of three pharmacologically significantly used drugs i.e., Chloroquine phosphate (CP), Acefylline piperazine (AP) and Gentamicin sulfate (GS) have been carried out in aqueous (aq), aqueous polyethylene glycol (aq-PEG) and aqueous polyvinyl pyrrolidone (aq-PVP) solvent systems within concentration range (0.02–0.1 ± 0.001 mol.dm−3) at different temperatures (293.15–318.15 K) with the interval of 5 K. Density data were used to evaluate volumetric properties of drugs (CP, AP and GS) by apparent molar volume, partial molar volumes, molar expansibilities and isothermal expansion coefficient. ϕ E ° provides information about the absence or presence of a caging or packing effect. Partial molar transfer volume was also calculated to study the hydrophilic/hydrophobic interactions in aq-PEG and aq-PVP solvent systems. The results are interpreted in terms of drug–solvent and drug-drug interactions and structure making or breaking abilities of drugs in aq, aq-PEG and aq-PVP solvent systems. [ABSTRACT FROM AUTHOR]

A gentamicin-loaded hydroxyapatite/collagen bone-like nanocomposite (GNT-HAp/Col) was fabricated and evaluated for its absorption–desorption properties, antibacterial efficacy, and cytotoxicity. The hydroxyapatite/collagen bone-like nanocomposite (HAp/Col) powder was mixed with gentamicin sulfate (GNT) in phosphate-buffered saline (PBS) at room temperature. After 6 h mixing, the GNT adsorption in all conditions reached plateau by Langmuir’s isotherm, and maximum GNT adsorption amount was 34 ± 7 μg in 250 μg/mL GNT solution. Saturated GNT-loaded HAp/Col powder of 100 mg was soaked in 10 mL of PBS at 37 °C and released all GNT in 3 days. A shaking culture method for a GNT extraction from the GNT-HAp/Col and an inhibition zone assay for the GNT-HAp/Col compact showed antibacterial efficacy to Escherichia coli (E. coli) at least for 2 days. From the release profile of the GNT from the GNT-HAp/Col powder, antibacterial efficacy would affect E. coli at least for 3 days. Further, no cytotoxicities were observed on MG-63 cells. Thus, the GNT-HAp/Col is a good candidate of bioresorbable anti-infection bone void fillers by prevention initial infections, which is the primary cause of implant-associated infection even for rapid bioresorbable materials. [ABSTRACT FROM AUTHOR]

Featured Application: The resulting systems are promising for drug delivery and controlled release of bioactive drug molecules. New hybrid nanosystems containing the antibacterial substances dioxidine or gentamicin sulfate with bioactive metal (Ag, Cu) nanoparticles have been obtained by a cryogenic freeze-drying method and incorporate further the nanocomposites thus obtained into the cryogenically structured biopolymeric matrices based on gelatin, calcium alginate, and chitosan. FTIR, UV-visible, and NMR spectroscopy, TEM and SEM microscopy data show that the resulting systems consist of wide-porous polymer sponges (pore diameters, 10–200 μm) that contain antibacterial drugs and silver (2–30 nm) or copper (1–5 nm) nanoparticles. The investigation showed that these systems ensure a gradual release of dioxidine (from 40 min up to 3 days), depending on the nature of the matrix and its microstructure. The higher activity of hybrid composites based on nanometals and dioxidine or incorporated into cryostructured biopolymer matrices against the bacterial strains of Escherichiacoli52,Staphylococcusaureus 144 is demonstrated as compared to the individual components in the same matrices. [ABSTRACT FROM AUTHOR]

A dual drug delivery system capable of simultaneous release in a sustained manner a hydrophilic and a hydrophobic drug was prepared, consisting of electrospun poly(lactic acid) (PLA) fibers embedded with halloysite nanotubes (Hal). The hydrophobic drug (dexamethasone, DEX) was directly dissolved in the polymer solution and the hydrophilic drug (gentamicin sulfate, GS) was pre-loaded into Hal. Prior to drug loading, Hal were subjected to an acid treatment to enhance their drug loading capacity. The efficacy of the treatment was confirmed by the increase of the BET surface area and pore volume, determined by nitrogen adsorption/desorption isotherm measurements, and by an increase in GS drug loading (from 18% w /w to 25% w /w), determined by thermogravimetry. Morphologically, the fibers with or without Hal exhibited similar smooth surfaces, with no obvious signs of Hal in the composite fibers, indicating that Hal were well embedded in the fibers. In vitro release tests showed the ability of the composite electrospun fibers to release the two loaded drugs simultaneously in a sustained manner for three weeks, in a biphasic pattern characterized by a burst release in the first 2–3 days followed by a gradual, almost constant release. Furthermore, the antibacterial activity of all GS loaded fibers against Staphylococcus aureus was confirmed by a disc diffusion test. In conclusion, the developed electrospun fibers based on a "nanoparticles in micro/nanofibers" structure proved to be an effective system for the sustained co-delivery of two drugs with opposite water affinities. [Display omitted] • Composite electrospun fibers of poly(acid lactic)/halloysite for dual drug delivery. • Hydrophilic drug (gentamicin sulfate) and hydrophobic drug (dexamethasone). • Gentamicin pre-loaded into acid treated halloysite; dexamethasone directly dispersed. • Gentamicin loading enhanced by halloysite acid treatment. • Simultaneously sustained release of gentamicin and dexamethasone for three weeks. [ABSTRACT FROM AUTHOR]

Microbial infections occurring during bone surgical treatment, the cause of osteomyelitis and implant failures, are still an open challenge in orthopedics. Conventional therapies are often ineffective and associated with serious side effects due to the amount of drugs administered by systemic routes. In this study, a medicated osteoinductive and bioresorbable bone graft was designed and investigated for its ability to control antibiotic drug release in situ. This represents an ideal solution for the eradication or prevention of infection, while simultaneously repairing bone defects. Vancomycin hydrochloride and gentamicin sulfate, here considered for testing, were loaded into a previously developed and largely investigated hybrid bone-mimetic scaffold made of collagen fibers biomineralized with magnesium doped-hydroxyapatite (MgHA/Coll), which in the last ten years has widely demonstrated its effective potential in bone tissue regeneration. Here, we have explored whether it can be used as a controlled local delivery system for antibiotic drugs. An easy loading method was selected in order to be reproducible, quickly, in the operating room. The maintenance of the antibacterial efficiency of the released drugs and the biosafety of medicated scaffolds were assessed with microbiological and in vitro tests, which demonstrated that the MgHA/Coll scaffolds were safe and effective as a local delivery system for an extended duration therapy—promising results for the prevention of bone defect-related infections in orthopedic surgeries.

Abstract—Nanoparticles of iron and magnetite, which have a high potential with respect to their magnetic properties, as well as antibacterial and antiviral activity, are included in hybrid nanosystems with antibacterial preparations of dioxidine and gentamicin sulfate by cryochemical synthesis. The composition, morphology, and antibacterial activity of the resulting systems were characterized by XRD, TEM, UV and IR spectroscopy, low-temperature nitrogen adsorption, and the disk diffusion test. [ABSTRACT FROM AUTHOR]

Treatment of postsurgical infections, associated with orthopedic surgeries, has been a major concern for orthopedics. Several strategies including systematic and local administration of antibiotics have been proposed to this regard. The present work focused on fabricating alginate (Alg) modified brushite (Bru) cements, which could address osteogeneration and local antibiotic demands. To find the proper method of drug incorporation, Gentamicin sulfate (Gen) was loaded into the samples in the form of solution or powder. Several characterization tests including compression test, morphology, cytotoxicity, and cell adhesion assays were carried out to determine the proper concentration of Alg as a modifier of the Bru cement. The results indicated that addition of 1 wt% Alg led to superior mechanical and biological properties of the cement. Moreover, Alg addition changed the morphology of the cement from plate and needle‐like structures to petal‐like structure. Fourier transform infrared spectroscopy results confirmed the successful loading of Gen on the cements, specifically when Gen solution was used, and X‐Ray Diffractometer result indicated that Gen caused a decrease in crystalline size. Furthermore, thermal analysis revealed that Gen‐loaded sample had more stable structure as the transformation temperature slightly shifted to a higher one. The stability study confirmed the chemical stability and adequate mechanical performance of the cements within 1 month of soaking time. Finally, the addition of Alg has a positive impact on the release behavior at low concentration of Gen solution so that 20% decrease within 2 weeks of release experiment was remarkably detected. [ABSTRACT FROM AUTHOR]

Necrotizing enterocolitis (NEC) is the leading cause of death from gastrointestinal disease in premature infants treated in neonatal intensive care unit (NICU). At the present time the unified universally accepted set of informative diagnostic criteria has not been developed yet to allows specifically determine the stage of the disease for the diagnose and treatment strategy. That is why comparing the results of various NEC treatment programs is very difficult. at the Department of pediatric Surgery and Division of Neonatology of Medical University of Graz (austria) the implementation of NEC prevention protocol resulted in a very low incidence of NEC. The Graz protocol consists originally of enteral application of a probiotic (Lactobacillus rhamnosus), in combination with enteral application of an antibiotic (Gentamicin) and an antifungal substance (Nystatin). Methods: The preventive multi-modal 3-component NEC prophylaxis scheme was implemented for NEC treatment in December of 2016 in Neonatology Intensive Care Unit of "Muratsan" clinical complex of Yerevan State Medical University. The retrospective observational study was performed to assess the effectiveness of multi-modal 3-component NEC prophylaxis scheme used as part of the treatment among patients with NEC during 01.12.2015-30.11.2016 (period a), 01.12.2016-30.11.2017 (period B) and 01.12.2017-30.11.2018 (period C). all observed patients were divided in to intervention and control groups. Results: The mortality rate in control group was 38 infants (40%) compared to the intervention group was 13 infants (13%) (p=0·0001). The implementation of multi-modal 3-component NEC prophylaxis scheme into treatment protocol for NEC resulted in reduction of NEC development from 37% to 12%. Newborns' total mortality decreased from 11% to 6%, wherein the NEC mortality decreased from 16% to zero, and mortality with NeC diagnose included decreased from 34% to 14%. The number of advanced NeC decreased from 33% to 2% and it should be noted that the number of surgical interventions decreased from 21 to zero. The complete recovery at discharge increased from 50% to 86%. Conclusion: The implementation of multi-modal 3-component NEC prophylaxis scheme into treatment protocol for NeC shows significantly reduction in NEC associated morbidity and mortality. The NEC development process in NICU also shows the positive dynamic after multi-modal 3-component NEC prophylaxis scheme administration among newborns with high risk of NeC development. [ABSTRACT FROM AUTHOR]

Poly(l-lactic acid) (PLLA) scaffolds were prepared by a particulate leaching method using sodium chloride (NaCl) with the size of 300–425 µm as a particulate leaching. The PLLA/NaCl weight ratios were varied to be 1:8, 1:10, 1:12, and 1:15. The gentamicin sulfate (GS)-loaded PLLA-sericin hybrid scaffolds were prepared by immersion of the PLLA scaffolds in sericin solution containing GS at a concentration of 5 mg mL−1 and subsequently freeze-drying. From the results, the pore sizes of the neat and the GS-loaded PLLA-sericin hybrid scaffolds ranged between 290 and 346 µm. The pore interconnectivity of these scaffolds increased with an increase in the amount of NaCl. Both the neat and the GS-loaded PLLA-sericin hybrid scaffolds that had been fabricated at PLLA/NaCl weight ratio of 1:15 showed high interconnected porous structure. Both the water retention and the weight loss increased with increasing NaCl content and submersion time. The increase in the porous structure of the scaffolds with the increasing NaCl content resulted in an observed decrease in the compressive modulus. Moreover, the cumulative released amounts of GS increased with increasing the porous structure of the scaffolds. All the GS-loaded PLLA-sericin hybrid scaffolds showed high activity against the growth of both E. coli TISTR 780 and S. aureus TISTR 1466. Lastly, all the GS-loaded PLLA-sericin hybrid scaffolds were proven non-toxic to MC3T3-E1 cells, indicating their potential uses for bone tissue engineering. [ABSTRACT FROM AUTHOR]

Abstract We investigated the suitability of 3D printed calcium phosphate scaffolds as drug carriers. The 3D powder printing process utilized α-tricalcium phosphate (α-TCP) as a solid phase and deionized water with 2.5% disodium hydrogen phosphate as a setting accelerator. The antibiotic gentamicin sulfate was incorporated by mixing it into α-TCP powder before printing. Two different concentrations of gentamicin (3 wt%, 7 wt%) were used to study the correlation between drug release kinetics and gentamicin content in the scaffolds. The scaffolds were hardened at 100% humidity. The synthesized scaffolds were characterized in terms of morphology, composition, mechanical strength, in vitro bioactivity and drug release kinetics. X-ray diffraction (XRD) analysis revealed that the α-TCP converted into calcium deficient hydroxyapatite (CDHA) during the printing process. Scanning electron microscopy (SEM) showed the typical needle-like structure of CDHA. Gentamicin release was investigated for a period of two weeks with an initial burst release. The produced scaffolds formed calcium enriched apatite crystals on their surface after three days of incubation in simulated body fluid. [ABSTRACT FROM AUTHOR]

Purpose: Direct delivery of aminoglycosides to the lungs was under extensive evaluations during the last decades. Because of large particle size, low density and porous structure, large porous particles (LPPs) are versatile carriers for this purpose. In this study, poly (lactic-co-glycolic acid) (PLGA) LPPs encapsulating gentamicin sulfate were prepared and in vitro characteristics of their freeze-dried powder as a dry powder inhaler (DPI) were evaluated. Methods: To prepare PLGA LPPs, a double emulsification-solvent evaporation method was optimized and gentamicin sulfate was post-loaded in the LPPs. in vitro characteristics including morphological features, thermal behavior, aerodynamic profile and cumulative drug release were evaluated by the scanning electron microscope (SEM), differential scanning calorimetry (DSC), next-generation cascade impactor (NGI) and Franz diffusion cell respectively. Results: The obtained results revealed that the preparation method was capable to produce spherical large homogenous highly porous particles. 94% of gentamicin sulfate released from LPPs up to 30 minutes. Mass median aerodynamic diameter (MMAD) and fine particle fraction (FPF) were 4.9 µm and 39% respectively. Conclusion: In this study, dry powder formulation composed of PLGA LPPs encapsulating gentamicin sulfate showed a promising in vitro behavior as a pulmonary delivery carrier. Improvements on the aerodynamic behavior and in vivo evaluations recommended for further developments. [ABSTRACT FROM AUTHOR]

Abstract Batch-injection analysis (BIA) with amperometric detection, using a boron-doped diamond (BDD) electrode, was developed for the determination of gentamicin sulfate (total components). System was operated at +2000 mV with acetate buffer (1.0 × 10−2 mol L−1; pH 4.40) as supporting electrolyte. Oxidation of analyte occurred right after the analyte solution plug (60 μL) reaches the surface of the electrode. Solid-phase extraction, using a cartridge packed with a kanamycin-imprinted polymer, was used to improve selectivity in determinations. The instrumental precision was <3% and the instrumental limit of quantification was 2.7 × 10−6 mol L−1 (1.5 μg mL−1). The analytical frequency was 90 measurements h−1 and no memory effect was observed between sequential measurements. The performance of the proposed method was compared with that obtained by using HPLC with molecular absorption spectrophotometric detection (after chemical derivatization of the analyte with o ‑phthalaldehyde). The method was applied in injectable pharmaceutical formulations with recoveries close to 100%. Highlights • Gentamicin sulfate was determined by batch-injection analysis with amperometry. • A boron-doped diamond enabled the irreversible oxidation of gentamicin sulfate. • The method for gentamicin requires no chemical derivatization of the analyte. • Analytical frequency was 90 analysis h−1. • Selectivity achieved by using kanamycin-imprinted polymer. [ABSTRACT FROM AUTHOR]

Abstract This work investigates the immobilization of the antibiotic gentamicin sulfate (GS) in electrospun fiber mats composed of poly(lactic acid) (PLA), poly(ε-caprolactone) (PCL) and the copolymer poly(lactic-co-glycolic acid) (PLGA). Since GS is highly water soluble but weakly soluble in the organic solvents commonly used in the electrospinning process, two methods of immobilization were investigated: by suspension electrospinning, in which GS particles were directly dispersed in the polymeric organic solutions, and by emulsion electrospinning, in which GS was solubilized in an aqueous phase that was then dispersed in the organic polymeric solution containing the surfactant SPAN80. Fibers with distinct diameters and morphologies were obtained for the different methods and compositions. Contrary to the fibers prepared by suspension electrospinning, emulsion electrospinning based fibers exhibited an excellent wettability, allegedly due to the effect of the surfactant SPAN80. Despite the differences between both methods the produced mats presented similar GS release profiles, with a considerable burst release in the first 8 h followed by a gradual release of the remaining drug during the next 4–6 days. Finally, all GS loaded fiber mats proved to have an antibacterial effect against the bacterial strain Staphylococcus aureus. Graphical abstract Unlabelled Image Highlights • GS was immobilized in PCL, PLA, PLGA or PLGA/PLA electrospun fibers by two methods. • Mats prepared by emulsion electrospinning displayed and excellent wettability. • Emulsion and suspension prepared fiber mats presented similar GS release profiles. • PLGA emulsion electrospinning mat had the most sustainable release profile. • All mats show antibacterial activity against Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

The retrospective study was performed to assess the effectiveness of multimodal 3-component necrotizing enterocolitis prophylaxis scheme used among patients with necrotizing enterocolitis during 01.12.2016-30.11.2017 (period B) compared to the results of 01.12.2015-30.11.2016 (period A) without necrotizing enterocolitis prophylaxis. The investigation included 71 newborns with necrotizing enterocolitis. According to the hospital records, 45 newborn infants were exposed to multimodal 3-component necrotizing enterocolitis prophylaxis scheme and 26 were not. The descriptive study was performed to evaluate the dynamics of necrotizing enterocolitis mortality and stages over 2016-2017 among the newborns admitted to "Muratsan" university hospital of Yerevan State Medical University after M. Heratsi. In total, 1429 medical records, registered during periods A and B were investigated. Necrotizing enterocolitis rate was increasing from 2011 to 2017. Significant difference (p<0.01) was found between the multimodal necrotizing enterocolitis prophylaxis exposure and the number of necrotizing enterocolitis perforation cases (12 cases out of 70 in period A and 0 cases out of 45 in period B). During period B, after introduction of multimodal 3-component necrotizing enterocolitis prophylaxis to 45 newborns, no cases of surgical operations have been registered as compared with 14 cases among the 70 newborns not exposed to necrotizing enterocolitis prophylaxis scheme (p<0.01) during period A. Significant association was found in number of death cases (p<0.01) among 45 newborns during period B (5 cases without necrotizing enterocolitis) and non-exposed 70 newborns during period A (24 cases). An introduction of multimodal 3-component necrotizing enterocolitis prophylaxis scheme among newborns with necrotizing enterocolitis is associated with significant decrease in the number of necrotizing enterocolitis cases at stages 3A, 3B and related deaths. Currently, the research continues to identify further positive effects of multimodal 3-component necrotizing enterocolitis prophylaxis to estimate the possible influence of necrotizing enterocolitis prophylaxis on condition of admitted newborns with different health problems. [ABSTRACT FROM AUTHOR]

New hybrid nanosystems containing the antibacterial substances dioxidine or gentamicin sulfate with bioactive metal (Ag, Cu) nanoparticles have been obtained by a cryogenic freeze-drying method and incorporate further the nanocomposites thus obtained into the cryogenically structured biopolymeric matrices based on gelatin, calcium alginate, and chitosan. FTIR, UV-visible, and NMR spectroscopy, TEM and SEM microscopy data show that the resulting systems consist of wide-porous polymer sponges (pore diameters, 10−200 μm) that contain antibacterial drugs and silver (2−30 nm) or copper (1−5 nm) nanoparticles. The investigation showed that these systems ensure a gradual release of dioxidine (from 40 min up to 3 days), depending on the nature of the matrix and its microstructure. The higher activity of hybrid composites based on nanometals and dioxidine or incorporated into cryostructured biopolymer matrices against the bacterial strains of Escherichia coli 52, Staphylococcus aureus 144 is demonstrated as compared to the individual components in the same matrices.

Cryochemical modification methods are used to obtain hybrid composites of the antibacterial drug gentamicin sulfate, as well as copper and iron nanoparticles, which are promising precursors of the targeted drug delivery systems. The resulting systems are antibiotic nanoparticles of 50 to 300 nm, including copper and iron nanoparticles of 1 to 20 nm (according to the results of physicochemical analysis by IR spectroscopy, X-ray diffraction analysis, dynamic light scattering, and scanning and transmission microscopy). The composites obtained showed higher antibacterial activity against E. coli, P. aeruginosa, and B. cereus compared to the individual components. [ABSTRACT FROM AUTHOR]