Carbomer 934P Research Articles

The impact of isopropanol and carbomer type on physicochemical characteristics of bioadhesive thermoresponsive platforms for eprinomectin delivery

Environmentally responsive systems composed of poloxamer 407 (P407) and different carbomers were investigated for eprinomectin delivery, as they can show improved properties for skin administration and permeation. Eprinomectin shows great efficacy against endo and ectoparasites, but its hydrophobicity is a challenge for the development of formulations. This work aimed to evaluate the influence of P407 amount, carbomer type and isopropyl alcohol (IA) concentration on sol-gel transition, compressional, rheological, drug release, bioadhesive and skin permeation properties of designed systems for topical administration of eprinomectin. Systems composed of different amounts of P407 and Carbomer 974P or 934P were proposed. The influence of IA amount and the eprinomectin presence was also investigated. Drug and IA reduced the structuring capacity and the compressional properties of systems. Preparations displayed bioadhesive force influenced by the carbomer type and drug presence. The higher P407 amount, the presence of C974P and the temperature increase enhanced the bioadhesiveness and structuring of systems. The selected formulations displayed drug release controlled by anomalous transport, and the formulations improved the bovine skin permeation of eprinomectin. P407 (17.5 %), 15 % IA, 0.3 % C974P and 0.5 % eprinomectin showed rendered an efficient system for controlled topical delivery and suggest it is worthy of in vivo evaluation.

Environmentally responsive systems for topical administration of copaiba oil-resin: The effect of carbomer 974P on the mechanical, rheological, drug release and skin permeation

Topical wound therapy using copaiba oil-resin (CO) can be improved by combining it with a thermoresponsive bioadhesive release system. Emulgel systems composed of the bioadhesive carbomer 974P (C974P) and the thermoresponsive poloxamer 407 (P407) can prolong the CO contact time with the skin and facilitate the drug permeation through the skin layers. The aim of this work was to develop and investigate the C974P's effect on rheological, mechanical, bioadhesive, in vitro drug release and ex vivo skin permeation properties of this system. The system development was based on a 23 (plus two central points) factorial design and the influence of different amounts of C974P on formulations was investigated. C974P enabled the formation of viscous and stable emulgels, and could structure with P407 and CO, resulting on physicochemical stable formulations. Formulation composed of 0.5 % (w/w) C974P, 20 % (w/w) P407 and 8 % (w/w) CO (F8) displayed improved properties. F8 exhibited extended release, enhanced bioadhesive strength, improved hardness, compressibility, elasticity, adhesiveness, cohesiveness, pseudoplasticity with yield value, thixotropy, and high viscoelasticity. It also displayed skin permeation and retention. The P407's high capacity to form micelles with CO enabled their integration into the polymeric matrix formed by C974P, resulting in viscous and stable gel.

Effect of propolis and polymer content on mechanical, bioadhesive and biological properties of nanostructured film forming platforms for topical drug delivery

Film form systems (FFS) composed of thermoresponsive and bioadhesive polymers have shown properties for the improvement of topical application. FFS are easy for administration, can increase the local residence time, control the drug delivery and improve the skin permeation. Propolis displays important biological properties like anticancer, healing, antimicrobial, antioxidant and can improve the structuring of FFS. It is a safe bioactive compound for wound healing and the treatment of skin diseases. However, propolis displays drawbacks for administration. The aim of this work was to evaluate the effect of polymeric and propolis composition on morphological, rheological, bioadhesive, drug release and skin permeation properties of designed FFS. In-vitro cytotoxicity, antitumoral and wound healing activity were also evaluated. Formulations composed of different amounts of polymers and propolis were proposed. The presence of propolis enhanced the bioadhesiveness and structuring of FFS. They displayed excellent capacity to form nanostructured film, displaying controlled propolis delivery and improved skin permeation. FFS were not cytotoxic and displayed in-vitro antitumoral activity and stimulated the cell migration. The selected preparations containing propolis extract (12%, w/w) and carbomer 974P or polycarbophil (0.25%, w/w) indicate a potentially advantageous role to be topically administered and suggest they are promissory formulations for clinical evaluation.

Comparison of In Vitro Corneal Permeation and In Vivo Ocular Bioavailability in Rabbits of Three Marketed Latanoprost Formulations.

All latanoprost formulations currently available for the treatment of glaucoma or ocular hypertension contain the same concentration of latanoprost (0.005%) but differ in excipients, which may affect corneal drug permeability or stability. This study aimed at comparing corneal penetration of three marketed latanoprost solutions with different excipient formulations in invitro and invivo drug permeability studies. Three latanoprost formulations were tested under good laboratory practice conditions: a formulation containing benzalkonium chloride (BAK) but no surfactant (Preserved latanoprost); the same formulation except preservative-free (PF) without BAK or surfactant (SF) (PF SF latanoprost); and a different formulation without BAK but containing a non-ionic surfactant (MGHS 40 at 5%) combined with thickening agents (Carbomer 974P, Macrogol 4000) (PF latanoprost). Corneal permeation of latanoprost acid (LAT) was first determined invitro using a reconstructed human corneal epithelium tissue. Then, invivo pharmacokinetic studies were performed on pigmented rabbits, for which LAT concentration was measured in the aqueous humour (AH) and iris-ciliary body (ICB). Invitro, the cumulative transport of LAT was linear between 1h and 4h for preserved latanoprost and PF SF latanoprost, and LAT concentrations matched exactly at each timepoint. By contrast, the permeation of PF latanoprost was linear between 2h and 12h and was significantly lower than that of preserved latanoprost and PF SF latanoprost at 4 and 8h (p<0.001). In rabbits, the concentrations of LAT in AH and ICB were not statistically different between preserved latanoprost and PF SF latanoprost at each timepoint, except at 1h in ICB (p=0.005). By comparison, the LAT concentration of PF latanoprost was statistically (p<0.05) lower than that of preserved latanoprost and PF SF latanoprost in AH and ICB from 0.5 to 3h. BAK did not influence the corneal penetration of latanoprost in invitro and invivo studies. The formulation containing a non-ionic surfactant resulted in lower and slower ocular penetration compared with preserved or PF SF formulations. This raises questions about the relevance of BAK and some surfactants in enhancing corneal penetration of ocular formulations.

FORMULATION AND EVALUATION OF CETIRIZINE HYDROCHLORIDE pH TRIGGED IN-SITU OCULAR GEL

Objective: In the present research work, the aim was to prepare pH trigged in-situ ocular gel of Cetirizine Hydrochloride (CTZ) to improve its local bioavailability at the eye surface. Methods: CTZ in-situ ocular gel was prepared by the pH-trigged method. In-situ CTZ ocular gel was prepared by a pH-sensitive gelling agent (Carbomer) with a one-viscosity builder polymer (HPMC E4M). All formulation was evaluated for appearance, pH, viscosity at different pH, gelling capacity, % drug content, and drug release. Nine formulations were prepared and optimized successfully using 32 factorial designs. Optimization was done by DoE software version Version 13.0.10.064. Results: All nine formulations of in-situ ocular gel were subjected to evaluation. Out of 9 formulations, F3 had a good gelling capacity with the minimum amount of polymer. The appearance of the optimized formulation was translucent and homogenous. The pH of the F3 formulation is 5.55±0.07, which is good for maintaining formulation in the solution stage. Viscosity at 20 RPM of F3 formulation at pH 5.5 is 837.30±1.00 cps; this range of viscosity has good flow properties. Viscosity at 20 RPM of F3 formulation at pH 7.4 is 6800.74±1.58cps; this range of viscosity has a good gelling capacity which helps to drug retain at the eye surface. Drug content is 100.16±0.53%. Drug release at 300 min is 69.22±2.12, it can say that the drug may be retained for more than 300 min at the eye surface, which is good for reducing dosing frequency. Conclusion: CTZ was successfully formulated in pH triggered in-situ gelling system using Carbomer 974P in combination with HPMC E4M. The prepared in-situ gel is easily converted from solution stage to gel stage at the pH of the eye so we can say that the drug in the in-situ ocular gel is more bioavailable than conventional ophthalmic solution In vitro results indicated that the in-situ gel system is a viable alternative to conventional ocular drops by virtue of its ability to sustain drug release.

On the role of polymeric hydrogels in the thermal response of gold nanorods under NIR laser irradiation.

Hydrogels are 3D cross-linked networks of polymeric chains designed to be used in the human body. Nowadays they find widespread applications in the biomedical field and are particularly attractive as drug delivery vectors. However, despite many good results, their release performance is sometimes very quick and uncontrolled, being forced by the high in vivo clearance of body fluids. In this direction, the development of novel responsive nanomaterials promises to overcome the drawbacks of common hydrogels, inducing responsive properties in three-dimensional polymeric devices. In this study, we synthesized and then loaded gold nanorods (Au NRs) within an agarose-carbomer (AC)-based hydrogel obtained from a microwave-assisted polycondensation reaction between carbomer 974P and agarose. The photothermal effect of the composite device was quantified in terms of maximum temperature and spatial-temporal temperature distribution, also during consecutive laser irradiations. This work shows that composite Au NRs loaded within AC hydrogels can serve as a stable photothermal treatment agent with enhanced photothermal efficiency and good thermal stability after consecutive laser irradiations. These results confirm that the composite system produced can exhibit an enhanced thermal effect under NIR laser irradiation, which is expected to lead to great therapeutic advantages for the localized treatment of different diseases.

Development and evaluation of colon-specific releasing nanoemulsion/hydrogel pellets of camptothecin

Camptothecin-loaded nanoemulsion (CPT/NE), sodium alginate, carbomer and calcium chloride were chosen to prepare camptothecin-loaded nanoemulsion / hydrogel (CPT/NE/HG) pellets. The optimal formulation of CPT/NE/HG pellets was composed of a mixture of the CPT/NE to hydrogel (1:1, w/w) followed by solidification with 15.0% CaCl2 solution, and the hydrogel consisted of a mass ratio of 1:1 of sodium alginate (1.92 %, w/v) and carbomer 934P (2.20 %, w/v). The reconstitution of pellets showed that there were nanoemulsions, microemulsions or mixed micelles existed together in simulated colonic fluid (SCF). The camptothecin releasing from the CPT/NE/HG pellets was less than 20 % in simulated gastric fluid while more than 40% loaded camptothecin released in SCF, and the release process was conformed to be first-order kinetics. The in vivo imaging indicated that the CPT/NE/HG pellets were firstly aggregated in the stomach while the most pellets were destructed after reaching the colon. The inhibitory effect of CPT/NE/HG pellets on LoVo cell growth was significantly stronger than that of CPT solution.

Central Composite Design Screened Mastic Gum Abetted Mucoadhesive Microspheres of Amoxicillin Trihydrate for Exterminating H. pylori

Aim: Searching for a new polymer that can be used in pharmaceutical formulation is a laborious and cost oriented practice. To resolve this, researchers are in search of a cost-effective and reliable excipient. Synthetic polymers are costly, whereas natural ones are abundant and economical. In the same way, discovering a new drug is a horrendous process with time, cost, and approval. The study's goal is to investigate Mastic gum's mucoadhesive properties by incorporating it into mucoadhesive microspheres with Amoxicillin trihydrate as a model drug. Methods: Nine interpretations of mucoadhesive microspheres were made with carbomer 934P and varying proportions of mastic gum (MG). A central composite design with design expert software is used to check the impact of independent variables (mastic gum and carbomer 934 P levels) on entrapment efficacy and mucoadhesion time as the responses. As part of congeniality studies, the microspheres were examined for amoxicillin trihydrate (ATH) content and liberation. Results: Good quality microspheres were formed that showed suitability with the excipients and possessed appreciable outcomes for the tests conducted. The study expressed the equation for ATH entrapment as +82.70+0.1333A+6.40B+0.0500AB+ 0.0000A₂-2.80B₂ and the mucoadhesion time as +13.10+0.2500A+1.42B-0.0500AB+0.1500A₂+0.1500B₂. These equations indicate the impact of independent variables on the response studies. These equations discovered that ATH entrapment increased with an increase in MG levels in the formulations and that the mucoadhesion time was greater in formulations with higher MG levels. In formulations containing higher levels of MG, the drug release is slightly reduced. Conclusion: The study summarized that amoxicillin trihydrate is capable of good stomach-specific drug delivery by carbomer 934P and enhanced by mastic gum when prepared as mucoadhesive microspheres that are cost-effective, operational, and stable. This approach also resolves the gastric retention of ATH to eradicate H. pylori and the mastic gum has proved an anti-ulcer possession.

Paclitaxel-nanocrystals-loaded network thermosensitive hydrogel for localised postsurgical recurrent of breast cancer after surgical resection.

The recurrence of cancer after local surgery has been a difficult problem in the clinic for a long time. In recent years, local treatment via drug-loaded thermosensitive hydrogels have become a promising strategy to prevent cancer recurrence. Thus, a thermosensitive hydrogel based on poloxamer 407, poloxamer 188 and the bioadhesive excipient carbomer 974P was designed to locally release paclitaxel and prevent local tumour recurrence after direct smearing of the hydrogel at the site of injury in the surgical cavity. To improve the local drug concentration, paclitaxel was prepared into nanocrystals via a wet mill process. A series of studies were performed on this paclitaxel nanocrystal thermosensitive hydrogel (PTX-NCS-gel), including examination of its rheological properties and in vitro release and dissolution studies. Moreover, a postoperative tumour recurrence mouse model was established to evaluate the antitumour effects of this thermosensitive hydrogel. The results showed that PTX-NCS-gel had a clear, regular network structure with excellent temperature sensitivity and could be gelated within minutes at 33.1°C. Additionally, the rheological property investigation indicated that the hydrogel has proper viscoelasticity and self-recovery ability. In vivo imaging showed that PTX-NCS-gel inhibited both local tumour recurrence and distant metastasis. Moreover, PTX-NCS-gel has the following advantages: it is more convenient to administer, avoids strong allergic responses, and has fewer side effects on the liver and spleen. This hydrogel has the potential to serve as a powerful auxiliary medication to prevent postoperative local tumour recurrence.

Neem Fruit Mucilage-Aided Mucoadhesive Microspheres of Acyclovir Using 32 Factorial Design With Design-Expert Software

The study aims to investigate the mucoadhesive properties of neem fruit mucilage by incorporating it into mucoadhesive microspheres with Acyclovir (ACR) as a model drug. Nine interpretations of mucoadhesive microspheres were made with carbomer-934P and varying proportions of neem fruit mucilage (NFM). A central composite design with Design Expert software to check the impact of independent variables (neem mucilage and carbomer 934P levels) on entrapment efficacy and mucoadhesion time. As part of congeniality studies, the microspheres were examined for ACR content and liberation. The study revealed that ACR entrapment increased with increase in NFM levels in the formulations and that the mucoadhesion time was greater in formulations with higher NFM levels. In the formulations containing higher levels of NFM, the drug release was slightly reduced. Acyclovir is capable of good stomach-specific drug delivery by carbomer 934P and its delivery is enhanced by neem fruit mucilage when prepared as mucoadhesive microspheres.

Design of emulgel platforms for local propolis delivery: The influence of type and concentration of carbomer

Emulgel systems gelled by adding carbomer 934P (C934P) have shown suitable physicochemical characteristics for propolis delivery aiming the therapy of dermatological disorders. However, there are other types of carbomers toxicologically preferable with different and important physicochemical properties to be utilized in emulgel systems, such as Carbopol 974P (C974P) and Carbopol 971P (C971P). In this sense, this work investigated formulations of different carbomer types (C934P, C97P and C974P) and concentrations, according to a factorial design 32. The systems were evaluated as mechanical textural and rheological characteristics. The physical stability of formulations also enabled the selection of the best formulations, which were evaluated as in vitro drug delivery. The texture profile analysis showed that C934P and C974P, at 1% (w/w) concentration, were responsible for improved mechanical characteristics. These same formulations were the only ones that displayed stability against centrifugation and were selected to the other tests. When submitted to rheological analysis they showed non-Newtonian pseudoplastic behavior and were viscoelastic. Rheological and textural mechanical characteristics confirmed the influence of temperature, type, and concentration of carbomer in the systems. The incorporation of propolis increased the softness of systems, suggesting easy local administration. Thus, emulgels composed of C934P or C974P 1% (w/w) are promising systems for controlled release of propolis and are worthy of further studies.

Innovative ex vivo model of human herpetic keratitis to evaluate antiviral drugs: proof of concept with 0.15% ganciclovir ophthalmic gel

AbstractPurposeWe have recently developed and characterized a unique model of herpetic keratitis reproducing dendritic or geographic ulceration on human corneas stored in our corneal Bioreactor (BR). The BR is a multi‐application experimentation platform developed to keep the cornea alive for prolonged periods of time in a physiological environment of intraocular pressure and environmental renewal.AimTo evaluate whether this model can be used to test the efficacy of antiviral eye drops.MethodsHSV‐1 keratitis was obtained as previously described: paired corneas discarded from our eye bank were stored in the BR for 14 days (D) at 21 mmHg and 2.6 µl/min of medium renewal (CorneaMax, Eurobio, France) to allow epithelial regeneration. A superficial linear epithelial lesion was then made in the centre, followed incubation of the epithelial surface for 1 hr in a solution of 106 Plaque‐Forming Unit/mL HSV‐1. Three days post‐infection, 0.15% ganciclovir ophthalmic gel used with active molecule at 3.75 µg/ml was instilled on the cornea inside the BR, 3 times/day during 14D and 2 times/day during 5D. The gel was rinsed after 10 min with BSS. The paired cornea was treated similarly with the vehicle (carbomer 974P). Changes in epithelial ulceration size were monitored daily by non‐invasive imaging through the transparent BR windows. Histology and immunolabeling (HSV‐1 gpB, epithelial markers) were done at D40.ResultsFor the control corneas, the entire epithelium desquamated at D10. At D40 all keratocytes expressed gpB and endothelial cells partly disappeared. For ganciclovir‐treated corneas, only half of the epithelium desquamated at D14, then it began to regenerate during the third week to reach 1 to 3 epithelial layers at D40. Epithelial and endothelial cells were not infected (gpB‐). Some keratocytes were infected only in the periphery.ConclusionsModel of herpetic keratitis in the BR has a high potential to evaluate antiviral eye drops efficacy.

Plasmonic control of drug release efficiency in agarose gel loaded with gold nanoparticle assemblies

AbstractPlasmonic nanoparticles (NPs) are exploited to concentrate light, provide local heating and enhance drug release when coupled to smart polymers. However, the role of NP assembling in these processes is poorly investigated, although their superior performance as nanoheaters has been theoretically predicted since a decade. Here we report on a compound hydrogel (agarose and carbomer 974P) loaded with gold NPs of different configurations. We investigate the dynamics of light-heat conversion in these hybrid plasmonic nanomaterials via a combination of ultrafast pump-probe spectroscopy and hot-electrons dynamical modeling. The photothermal study ascertains the possibility to control the degree of assembling via surface functionalization of the NPs, thus enabling a tuning of the photothermal response of the plasmon-enhanced gel under continuous wave excitation. We exploit these assemblies to enhance photothermal release of drug mimetics with large steric hindrance loaded in the hydrogel. Using compounds with an effective hydrodynamic diameter bigger than the mesh size of the gel matrix, we find that the nanoheaters assemblies enable a two orders of magnitude faster cumulative drug release toward the surrounding environment compared to isolated NPs, under the same experimental conditions. Our results pave the way for a new paradigm of nanoplasmonic control over drug release.

ATENOLOL MICROPARTICLES BY TWO-FACTOR TWO-LEVEL CENTRAL COMPOSITE DESIGN

Objective: The objective of this research was to formulation, optimization, and evaluation of gastric-mucoadhesive microparticles which contains selective β1 receptor antagonist atenolol.&#x0D; Methods: The following chemicals were used, atenolol (Gangwal Chemicals Pvt. Ltd., Mumbai), ethyl cellulose (EC) (Loba Chemie Pvt. Ltd., Mumbai), Carbopol 940 (Loba Chemie Pvt. Ltd., Mumbai), liquid paraffin (Arora Pharmaceuticals Pvt. Ltd., New Delhi), and Span 80 (Central Drug House (P) Ltd., New Delhi). Microparticles were prepared by the emulsification solvent evaporation technique using polymers of Carbomer 934p (CP) and EC. Disc formulations were prepared by direct compression technique from microparticles. Microparticles of combined polymers were designed according to 22 factorial central composite design (CCD), taking EC concentration and surfactant concentration as the independent variables. A total of 13 batches were prepared. The dependent variables were percentage of % drug released and % entrapment efficiency.&#x0D; Results and Discussion: All evaluation tests were done for the prepared 13 formulations, such as percentage entrapment efficiency, percentage drug release, swelling index, percentage yield, and particle size analysis. The entrapment efficiency of optimized formulation was found to be 72.02%. The entrapment efficiency increases with increase in EC concentration and stirring speed. Optimized formulation was further subjected to study of drug release kinetics based on the R2 value; it was observed that Korsmeyer Peppas release kinetic model was found to be best suited for formulation of atenolol with EC: carbopol 934 by solvent evaporation method.&#x0D; Conclusion: The optimized formulation of microparticles containing atenolol was found to be homogeneous, good appearance and had well flow properties and better release kinetics.

The effect of carbomer 934P and different vegetable oils on physical stability, mechanical and rheological properties of emulsion-based systems containing propolis

Abstract Semi-solid emulsion systems constitute important platforms for drug delivery, due to the easiness of administration, increasing residence time and also improve the drug availability. They are usually stabilized by emulsifiers and hydrophilic polymers may be used to form a tridimensional network in the hydrophilic phase resulting in a structure than can disperse the hydrophobic phase and the drug. These systems can be administered by oral, parenteral, and topical routes as platforms for delivery of biologically active agents from different origins such as mineral, animal or vegetal. Propolis has a complex chemical composition and displays many important biological activities (antibacterial, fungicidal, antioxidant, antiviral, anti-inflammatory, immunostimulant, anti-cancer, antiulcer, hypotensive and cytostatic). Propolis ethanolic extract (PE) and extract of propolis by-product (BPE) are usually utilized in therapeutics. In this work, three vegetable oils (passion fruit, andiroba and sweet almond oils) were used to develop emulsion-systems composed of Carbopol 934P (C934P) for propolis delivery. The mechanical and rheological properties of formulations were investigated to select potential emulsion systems. A factorial design was employed to determine the influence of C934P concentration and the different vegetable oils on the physicochemical characteristics of systems, considering the presence of PE or BPE. Emulsion systems displayed physicochemical stability and mechanical characteristics dependent of C934P 1% (w/w). Formulations displayed pseudoplastic flow behavior and viscoelasticity dependent of vegetable oil type, temperature and type of propolis extract. The results indicated that the PE resulted in a more structured emulsion system due to the greater content of resin and gum than the BPE. Emulsion systems displayed softness and are worthy of investigation intended the administration on the skin and mucous membranes.

Propranolol Hydrochloride Buccoadhesive Tablet: Development and In-vitro Evaluation.

Propranolol HCl is a beta blocker commonly used worldwide; however, it shows a low bioavailability due to its extensive first-pass metabolism. To overcome this problem, a novel drug delivery system such as buccoadhesive system might be helpful. The aim of the present investigation is to prepare the buccoadhesive tablet of propranolol HCl using different mucoadhesive polymers. Buccoadhesive tablets containing drug, lactose, and polymers such as HPMC K4M, carbomer 934P, PEO 8000000 and PEG 6000, in various concentrations, were prepared. The tablets were evaluated in terms of weight variation, thickness, hardness, friability, and mucoadhesive strength. Among thirteen prepared formulations, seven of them which had better physicochemical properties and mucoadhesive strength were undergone the release and swelling tests. Finally, two formulations were selected and uniformity, drug content, duration of mucoadhesion, and kinetic studies were performed for them. All polymers except PEG 6000 were appropriate for being used in buccal mucoadhesive systems. Formulation F1 was considered as the most desirable formulation as it exhibited appropriate mucoadhesive strength (43.93 ± 12.4 g), extended duration of mucoadhesion (19.15 ± 0.29 h) and suitable swelling ability while having a prolonged drug release over 12 h. Although the efficiency and mucosal irritation of propranolol HCl buccoadhesive tablets should be monitored under the in-vivo conditions, however, based on the results, it seems that such tablets can be considered as an alternative route to bypass the first pass metabolism of propranolol HCl.

Design of polymer-based antimicrobial hydrogels through physico-chemical transition.

The antimicrobial activity represents a cornerstone in the development of biomaterials: it is a leading request in many areas, including biology, medicine, environment and industry. Over the years, different polymeric scaffolds are proposed as solutions, based on the encapsulation of metal ions/particles, antibacterial agents or antibiotics. However, the compliance with the biocompatibility criteria and the concentration of the active principles to avoid under- and over-dosing are being debated. In this work, we propose the synthesis of a versatile hydrogel using branched polyacrylic acid (carbomer 974P) and aliphatic polyetherdiamine (elastamine®) through physico-chemical transition, able to show its ability to counteract the bacterial growth and infections thanks to the polymers used, that are not subjected to further chemical modifications. In particular, the antimicrobial activity is clearly demonstrated against Staphyloccoccus aureus and Candida albicans, two well-known opportunistic pathogens. Moreover, we discuss the hydrogel use as drug carrier to design a unique device able to combine the antibacterial/antimicrobial properties to the controlled drug delivery, as a promising tool for a wide range of biomedical applications.

3D culture of murine adipose-derived multipotent mesenchymal stromal cells in hydrogel based on carbomer 974P

Actual issues during tissue regeneration are to ensure the survival of transplanted cells at the site of their application and further activity, especially in case of local pathological alterations such as inflammation and ischemia. For this purpose, the matrices that can not only fill the defects of tissues, but also be scaffolds for cells are developed.The aim of this study was to evaluate the effectiveness of 3D cultivation of murine adipose-derived multipotent mesenchymal stromal cells (MSMCs) in hydrogel based on carbomer 974P.Materials and methods. MSMCs were obtained from the adipose tissue of FVB-Cg-Tg(GFPU)5Nagy/J mice transgenic for GFP gene. The cells were phenotyped by flow cytometry and directly differentiated into osteogenic and adipogenic direction to confirm multipotent phenotype. MMSCs were cultured and directly differentiated into osteogenic direction in three-dimensional hydrogel scaffolds. For hydrogel preparation we used carbomer 974P with composition of glycerol, propylene glycol, triethylamine and agarose in original proportion.Results. The three-dimensional hydrogel based on carbomer 974P for the further engraftment with MMSCs was obtained. Modified protocols for the preparation of hydrogels based on carbomer and agarose and their rehydration by culture media for the 3D cultivation of adipose-derived MMSCs have been developed. The optimal concentration of MSMCs and the injection method for engraftment of hydrogels of the required form and size are selected. It was shown that adipose-derived MMSCs in 3D carbomer hydrogel preserve the potential of directed osteogenic differentiation.Conclusion. Three-dimensional hydrogel based on carbomer 974P is capable to support cells, provide the necessary cytoarchitectonics, maintain intercellular interactions, which can promote further long-term survival and specialization of graft.

Ophthalmic Microemulsion: Formulation Design and Process Optimization

The microemulsion systems, o/w, composed of castor oil, sesame oil, arachis oil, olive oil, polysorbate 20, polysorbate 80, Tyloxapol, Carbomer 974P, carboxymethyl cellulose sodium, hydroexthylecellulose, glycerine, propylene glycol, sodium chloride and purified water, taken at various amounts and in various combinations, were tested in order to assess their physical-chemical compatibility. All ingredients of the microemulsions were physiologically acceptable. Microemulsions were evaluated for the different parameters to access the effect of processing parameters on the globule size formation and stability. The stable microemulsion system was obtained for the formulation in which castor oil and polysorbate 80 was used. The following parameters were analyzed: description, pH, osmolality, viscosity, specific gravity, globule size, polydispersity index (PDI) zeta potential, surface tension, assay, in vitro Drug Release. The study made it possible to select the most stable microemulsion system meeting the requirements of eye drops. Thus, the proposed formulation and process were successfully developed and evaluated.

Microemulgel of Voriconazole: an Unfathomable Protection to Counter Fungal Contagiousness.

Fluconazole and ketoconazole both have poor minimum inhibitory concentration than voriconazole. Voriconazole had serious side effects in oral and intravenous doses. It has poor water solubility. The objective of the study was to prepare and optimize microemulgel of voriconazole for topical delivery. Formulation, development, and evaluation of voriconazole microemulgel for topical delivery. Oil and emulsifi ers selected were on the basis of equilibrium solubility study and emulsification property respectively. The pseudo-ternary plot and constrained simplex lattice design were applied for preparation of microemulsions. Microemulsions were subjected to micelle size, zeta potential, polydispersity index, and in vitro study. They were optimized by Design-Expert® 9.0.3.1 software. Formulation, development, evaluation and optimization of microemulgel were carried out. Microbial assay of an optimized batch of microemulgel was performed. Solubility of voriconazole in Parker Neem® oil was 7.51±0.14 mg/g. Acrysol™K-150: PEG-400 in 4:1 ratio had the highest area for microemulsion. 59.2% Acrysol™K-150, 14.8% PEG-400, 11% Parker Neem® oil, 15% rose water, and 1% voriconazole as an optimized batch of microemulsion was selected for preparation of microemulgel. Carbomer 934P found a good gelling agent in 0-2% w/w concentration. An optimized batch of microemulgel had 0.974 desirability value. An optimized batch of microemulgel and Nizral® cream had 37.32±0.63% and 26.45±0.63% zones of inhibition. Topical antifungal treatment was successfully achieved with voriconazole microemulgel.