Formulation and in vitro evaluation of carbopol 934-based modified clotrimazole gel for topical application

Efficacy of a Novel Melatonin-Loaded Gelatin Sponge in Palatal Wound Healing

OBJECTIVES

The aim of this research was to assess both clinically and histologically the effect of a topically applied melatonin-loaded gelatin sponge on palatal wound healing after graft harvesting.

METHODS

Twenty-six patients for whom free palatal graft procurement was indicated were divided equally into 2 groups. In the test group, the donor site was covered by a melatonin-loaded gelatin sponge, and in the control group the site was covered by a placebo-loaded gelatin sponge. Wound healing was evaluated on the day of surgery and at 7 and 14 days postsurgery using photo-digital planimetry. Histologic specimens were taken to verify healing type and rate. Pain was assessed via Visual Analogue Scale (VAS) for 7 days from the day of the surgery.

RESULTS

At the 7-day interval, photo-digital planimetry showed a significant decrease in the traced raw area (P = .04) in the test group compared with the control group and a significant increase in the mean area of immature epithelia (P = .04). At the 14-day interval, there was no statistically significant difference in any area of interest. Histologically, the application of melatonin was associated with accelerated healing and superior maturation at all follow-up time points. No significant differences were noted in VAS scores between the 2 groups.

CONCLUSIONS

Melatonin-treated tissue showed marked clinical improvement in the first week postsurgery, indicating an increased rate of healing. Similarly, histologic analysis revealed significant maturation at both time intervals. A melatonin-loaded gelatin sponge is a novel palatal wound dressing that can be used to improve wound healing outcomes and reduce patient morbidity.

In Vivo Wound Healing Potential and Molecular Pathways of Amniotic Fluid and Moringa Olifera-Loaded Nanoclay Films

Cutaneous wounds pose a significant health burden, affecting millions of individuals annually and placing strain on healthcare systems and society. Nanofilm biomaterials have emerged as promising interfaces between materials and biology, offering potential for various biomedical applications. To explore this potential, our study aimed to assess the wound healing efficacy of amniotic fluid and Moringa olifera-loaded nanoclay films by using in vivo models. Additionally, we investigated the antioxidant and antibacterial properties of these films. Using a burn wound healing model on rabbits, both infected and non-infected wounds were treated with the nanoclay films for a duration of twenty-one days on by following protocols approved by the Animal Ethics Committee. We evaluated wound contraction, proinflammatory mediators, and growth factors levels by analyzing blood samples. Histopathological changes and skin integrity were assessed through H&E staining. Statistical analysis was performed using SPSS software (version 2; Chicago, IL, USA) with significance set at p < 0.05. Our findings demonstrated a significant dose-dependent increase in wound contraction in the 2%, 4%, and 8% AMF-Me.mo treatment groups throughout the study (p < 0.001). Moreover, macroscopic analysis revealed comparable effects (p > 0.05) between the 8% AMF-Me.mo treatment group and the standard treatment. Histopathological examination confirmed the preservation of skin architecture and complete epidermal closure in both infected and non-infected wounds treated with AMF-Me.mo-loaded nanofilms. RT-PCR analysis revealed elevated concentrations of matrix metalloproteinases (MMPs) and vascular endothelial growth factor (VEGF), along with decreased levels of tumor necrosis factor-alpha (TNF-α) in AMF-Me.mo-loaded nanofilm treatment groups. Additionally, the antimicrobial activity of AMF-Me.mo-loaded nanofilms contributed to the decontamination of the wound site, positioning them as potential candidates for effective wound healing. However, further extensive clinical trials-based studies are necessary to confirm these findings.

Novel Transethosomal Gel Containing Miconazole Nitrate; Development, Characterization, and Enhanced Antifungal Activity

Miconazole nitrate (MCNR) is a BCS class II antifungal drug with poor water solubility. Although numerous attempts have been made to increase its solubility, formulation researchers struggle with this significant issue. Transethosomes are promising novel nanocarriers for improving the solubility and penetration of drugs that are inadequately soluble and permeable. Thus, the objective of this study was to develop MCNR-loaded transethosomal gel in order to enhance skin permeation and antifungal activity. MCNR-loaded transethosomes (MCNR-TEs) were generated using the thin film hydration method and evaluated for their zeta potential, particle size, polydispersity index, and entrapment efficiency (EE%). SEM, FTIR, and DSC analyses were also done to characterize the optimized formulation of MCNR-TEs (MT-8). The optimized formulation of MCNR-TEs was incorporated into a carbopol 934 gel base to form transethosomal gel (MNTG) that was subjected to ex vivo permeation and drug release studies. In vitro antifungal activity was carried out against Candida albicans through the cup plate technique. An in vivo skin irritation test was also performed on Wistar albino rats. MT-8 displayed smooth spherical transethosomal nanoparticles with the highest EE% (89.93 ± 1.32%), lowest particle size (139.3 ± 1.14 nm), polydispersity index (0.188 ± 0.05), and zeta potential (-18.1 ± 0.10 mV). The release profile of MT-8 displayed an initial burst followed by sustained release, and the release data were best fitted with the Korsmeyer-Peppas model. MCNR-loaded transethosomal gel was stable and showed a non-Newtonian flow. It was found that ex vivo drug permeation of MNTG was 48.76%, which was significantly higher than that of MNPG (plain gel) (p ≤ 0.05) following a 24-h permeation study. The prepared MCNR transethosomal gel exhibited increased antifungal activity, and its safety was proven by the results of an in vivo skin irritation test. Therefore, the developed transethosomal gel can be a proficient drug delivery system via a topical route with enhanced antifungal activity and skin permeability.

Formulation and Characterization of Hesperidin-Loaded Transethosomal Gel for Dermal Delivery to Enhance Antibacterial Activity: Comprehension of In Vitro, Ex Vivo, and Dermatokinetic Analysis

In this study, hesperidin was loaded into a transethosome and was developed employing the rotary evaporator method. The formulation was optimized using the Box-Behnken design (BBD). The optimized HSD-TE formulation has a spherical shape, vesicle size, polydispersity index, entrapment efficiency, and zeta potential within the range of 178.98 nm; the PDI was 0.259 with a zeta potential of -31.14 mV and % EE of 89.51%, respectively. The in vitro drug release shows that HSD-TE exhibited the release of 81.124 ± 3.45% in comparison to HSD suspension. The ex vivo skin permeation showed a 2-fold increase in HSD-TE gel permeation. The antioxidant activity of HSD-TE was found to be 79.20 ± 1.77% higher than that of the HSD solution. The formulation showed 2-fold deeper HSD-TE penetration across excised rat skin membranes in confocal laser microscopy scanning, indicating promising in vivo prospects. In a dermatokinetic study, HSD-TE gel was compared to HSD conventional gel where TE significantly boosted HSD transport in the epidermis and dermal layers. The formulation showed greater efficacy than free HSD in the inhibition of microbial growth, as evidenced by antibacterial activity on the Gram-negative and positive bacteria. These investigations found that the HSD-TE formulation could enhance the topical application in the management of cutaneous bacterial infections.

Development of Soft Luliconazole Invasomes Gel for Effective Transdermal Delivery: Optimization to In-Vivo Antifungal Activity

Luliconazole (LZ) is a good candidate for the treatment of fungal infection topically but has limitations, i.e., poor solubility and poor permeability to skin. Due to these limitations, multiple administrations for a long time are required to treat the inflection. The aim of the present study was to develop the invasomes (IVS) gel of LZ to improve the topical antifungal activity. The IVS was prepared by the thin-film hydration method and optimized by Box-Bhekhen design software. The optimized LZIVS (LZIVSopt) has 139.1 ± 4.32 nm of vesicle size, 88.21 ± 0.82% of entrapment efficiency, 0.301 ± 0.012 of PDI, and 19.5 mV (negative) of zeta potential. Scanning microscopy showed a spherical shape of the vesicle. FTIR spectra showed there is no interaction between the drug and lipid. Thermogram showed that the LZ is encapsulated into the LZIVS matrix. LZIVSopt gel (LZIVSopt-G3) exhibited optimum viscosity (6493 ± 27 cps) and significant spreadability (7.2 g·cm/s). LZIVSopt-G3 showed 2.47-fold higher permeation than pure LZ-gel. LZIVSopt-G3 did not show any edema or swelling in the skin, revealing that the developed formulation is non-irritant. LZIVSopt-G3 exhibited significant inhibition of the fungus infection (C. albicans) in the infected rats. The finding concluded that IVS gel is a good carrier and an attractive approach for the enhancement of topical delivery of LZ to treat the fungal infection.

Nanostructured Lipid Carrier-Based Gel for Repurposing Simvastatin in Localized Treatment of Breast Cancer: Formulation Design, Development, and In Vitro and In Vivo Characterization

Simvastatin (SMV) is noticed as a repurposed candidate to be effective against breast cancer (BC). However, poor solubility, dose-limiting toxicities, and side effects are critical hurdles in its use against BC. The above drawbacks necessitate the site-specific (localized) delivery of SMV via suitable nanocarriers. Therefore, the present study intended to develop SMV nanostructured lipid carrier (NLC)-based gel using carbopol-934 as a gelling agent to achieve local delivery and improve patient compliance while combating BC. The SMV NLCs were fabricated by melt-emulsification ultrasonication technique using stearic acid as solid lipid, olive oil (OO) as liquid lipid, tween 20 as a surfactant, and PEG-200 as a co-surfactant, and optimized by Box-Behnken design. The optimized SMV-loaded NLCs displayed % entrapment efficiency of 91.66 ± 5.2% and particle size of 182 ± 11.9 nm. The pH of NLC-based gels prepared using a 2.0% w/v of carbopol-934 was found in the range of 5.3-5.6 while the viscosity was in the range of 5.1-6.6 Pa.S. Besides, NLC-based gels exhibited higher and controlled SMV release (71-76%) at pH 6.8 and (78-84%) at pH 5.5 after 48 h than SMV conventional gel (37%) at both pH 6.8 and 5.5 after 48 h. The ex vivo permeation of SMV from NLC-based gel was 3.8 to 4.5 times more than conventional gel. Notably, SMV-loaded NLCs displayed ameliorated cytotoxicity than plain SMV against MCF-7 and MDA-MB-231 BC cells. No substantial difference was noticed in the cytotoxicity of NLC-based gels and pure SMV against both cell lines. The SMV NLC-based gel exhibited the absence of skin irritation in vivo in the mice following topical application. In addition, the histopathological study revealed no alteration in the mice skin anatomy. Furthermore, the SMV-loaded NLCs and NLC-based gels were stable for 6 months at refrigerator conditions (4°C ± 2°C). Thus, the present research confirms that NLC-based gel can be a safe, efficacious, and novel alternative to treat BC.

Qbd-Based Approach to Optimize Niosomal Gel of Levosulpiride for Transdermal Drug Delivery

Poor aqueous solubility besides extensive hepatic first effect significantly decreases the oral absorption of levosulpiride, which in turn minimizes its therapeutic effectiveness. Niosomes have been extensively investigated as a transdermal vesicular nanocarrier to increase the delivery of low permeable compounds into and across the skin. This research work was to design, develop and optimize levosulpiride-loaded niosomal gel and to evaluate its prospects for transdermal delivery. The Box-Behnken design was used to optimize niosomes by analyzing the impact of three factors (cholesterol; X1, Span 40; X2, and sonication time; X3) on the responses (particle size, Y1, and entrapment efficiency, Y2). Optimized formulation (NC) was incorporated into gel and evaluated for pharmaceutical properties, drug release study, ex vivo permeation, and in vivo absorption. The design experiment data suggest that all three independent variables influence both response variables significantly (p < 0.01). Pharmaceutical characteristics of NC vesicles showed the absence of drug excipient interaction, nanosize (~102.2 nm), narrow distribution (~0.218), adequate zeta potential (−49.9 mV), and spherical shape, which are suitable for transdermal therapy. The levosulpiride release rates varied significantly (p < 0.01) between niosomal gel formulation and control. Greater flux (p < 0.01) was observed with levosulpiride-loaded niosomal gel than with control gel formulation. Indeed, the drug plasma profile of niosomal gel was significantly higher (p < 0.005), with ~3 folds higher Cmax and greater bioavailability (~500% higher; p < 0.0001) than its counterpart. Overall, these findings imply that the use of an optimized niosomal gel formulation can increase the therapeutic efficacy of levosulpiride and may represent a promising alternative to conventional therapy.

Formulation of Miconazole-Loaded Chitosan-Carbopol Vesicular Gel: Optimization to In Vitro Characterization, Irritation, and Antifungal Assessment

Miconazole nitrate (MN) is a poorly water-soluble and antifungal drug used for fungal infections. The present research work was designed to develop topical MN-loaded bilosomes (BSs) for the improvement of therapeutic efficacy. MZBSs were prepared by using the thin-film hydration method and further optimized by using the Box-Behnken statistical design (BBD). The optimized miconazole bilosome (MZBSo) showed nano-sized vesicles, a low polydispersity index, a high entrapment efficiency, and zeta potential. Further, MZBSo was incorporated into the gel using carbopol 934P and chitosan polymers. The selected miconazole bilosome gel (MZBSoG2) demonstrated an acceptable pH (6.4 ± 0.1), viscosity (1856 ± 21 cP), and spreadability (6.6 ± 0.2 cm²). Compared to MZBSo (86.76 ± 3.7%), MZBSoG2 showed a significantly (p < 0.05) slower drug release (58.54 ± 4.1%). MZBSoG2 was found to be a non-irritant because it achieved a score of zero (standard score) in the HET-CAM test. It also exhibited significant antifungal activity compared to pure MZ against Candida albicans and Aspergillus niger. The stability study results showed no significant changes after stability testing under accelerated conditions. MZ-loaded gels could serve as effective alternative carriers for improving therapeutic efficacy.

Efficacy of Graphene-Based Nanocomposite Gels as a Promising Wound Healing Biomaterial

The development of biocompatible nanocomposite hydrogels with effective wound healing/microbicidal properties is needed to bring out their distinguished characteristics in clinical applications. The positive interaction between graphene oxide/reduced graphene oxide (GO/rGO) and hydrogels and aloe vera gel represents a strong strategy for the advancement of therapeutic approaches for wound healing. In this study, the synthesis, characterization, and angiogenic properties of graphene-based nanocomposite gels have been corroborated and substantiated through several in vitro and in vivo assays. In this respect, graphene oxide was synthesized by incorporating a modified Hummer's method and ascertained by Raman spectroscopy. The obtained GO and rGO were uniformly dispersed into the aloe vera gel and hydrogel, respectively, as wound healing materials. These formulations were characterized via in vitro bio-chemical techniques and were found suitable for the appropriate cell viability, attachment, and proliferation. In addition, in vivo experiments were conducted using male Wistar rats. This revealed that the GO/rGO-based gels stimulated wound contraction and re-epithelialization compared to that of the non-treatment group. From the study, it is suggested that GO/rGO-based aloe vera gel can be recommended as a promising candidate for wound healing applications.

Pharmaceutical Incompatibility of Lubricating Gel Formulation Reduces Antibacterial Activity of Chlorhexidine Gluconate: In Vitro Study in Northern Thailand

Chlorhexidine gluconate (CHG) is a cationic disinfectant. The positive charge of CHG molecules binds to phospholipid's negative charge in bacterial cell walls, causing membrane disruption. The in vitro kinetic physical, chemical and biological incompatibilities of nine lubricating gels with 1% w/v CHG were investigated. Five containing anionic thickener, two containing nonionic thickener, and two containing cationic thickener were collected from hospitals in northern Thailand. All the anionic and nonionic lubricating gels significantly reduced (p < 0.05) the CHG amount after 5 min of exposure time from 12.54% to 54.99%, respectively. In contrast, the amount of CHG exposed with cationic lubricating gels was maintained. Antibacterial activity was significantly reduced to a 1.17-4.33 log10 reduction for Staphylococcus aureus ATCC25923 and a 1.07-3.52 log10 reduction for Escherichia coli ATCC25922 after 5 min exposure to all anionic and nonionic lubricating gels. In contrast, the two cationic lubricating gels maintained the antibacterial activity of the CHG solution (5.69 ± 0.14 and 5.45 ± 0.17 log10 reduction). The results suggest that anionic and nonionic thickeners in lubricating gel formulations may neutralize the positive charge and reduce the antibacterial activity of CHG, reducing its effectiveness as a disinfectant.

Rhamnolipid Nano-Micelles versus Alcohol-Based Hand Sanitizer: A Comparative Study for Antibacterial Activity against Hospital-Acquired Infections and Toxicity Concerns

Hospital-acquired infections (HAIs) are considered to be a major global healthcare challenge, in large part because of the development of microbial resistance to currently approved antimicrobial drugs. HAIs are frequently preventable through infection prevention and control measures, with hand hygiene as a key activity. Improving hand hygiene was reported to reduce the transmission of healthcare-associated pathogens and HAIs. Alcohol-based hand sanitizers are commonly used due to their rapid action and broad spectrum of microbicidal activity, offering protection against bacteria and viruses. However, their frequent administration has been reported to be associated with many side effects, such as skin sensitivity, skin drying, and cracks, which promote further skin infections. Thus, there is an essential need to find alternative approaches to hand sanitation. Rhamnolipids are glycolipids produced by Pseudomonas aeruginosa, and were shown to have broad antimicrobial activity as biosurfactants. We have previously demonstrated the antimicrobial activity of rhamnolipid nano-micelles against selected drug-resistant Gram-negative (Salmonella Montevideo and Salmonella Typhimurium) and Gram-positive bacteria (Staphylococcus aureus, Streptococcus pneumoniae). To the best of our knowledge, the antimicrobial activity of rhamnolipid nano-micelles in comparison to alcohol-based hand sanitizers against microorganisms commonly causing HAIs in Egypt—such as Acinetobacter baumannii and Staphylococcus aureus—has not yet been studied. In the present work, a comparative study of the antibacterial activity of rhamnolipid nano-micelles versus alcohol-based hand sanitizers was performed, and their safety profiles were also assessed. It was demonstrated that rhamnolipid nano-micelles had a comparable antibacterial activity to alcohol-based hand sanitizer, with a better safety profile, i.e., rhamnolipid nano-micelles are unlikely to cause any harmful effects on the skin. Thus, rhamnolipid nano-micelles could be recommended to replace alcohol-based hand sanitizers; however, they must still be tested by healthcare workers in healthcare settings to ascertain their antimicrobial activity and safety.

Topical delivery of curcumin-loaded transfersomes gel ameliorated rheumatoid arthritis by inhibiting NF-κβ pathway

Aim: To fabricate and evaluate curcumin-loaded transfersomes (Cur-TF) for the targeted delivery and enhanced therapeutic efficacy of curcumin for the treatment of rheumatoid arthritis (RA). Methods: Modified thin-film hydration method was used to prepare Cur-TF which were then embedded into carbopol-934 gel. They were further evaluated through in vitro techniques and in an in vivo arthritis model. Results: Cur-TF had optimal particle size, spherical morphology, high encapsulation efficiency and sustained drug release profiles. The Cur-TF gel had better in vitro skin penetration than plain curcumin. In vivo findings demonstrated improved clinical, histological and x-ray scores and reduced pro-inflammatory cytokines through NF-κβ inhibition. Conclusion: Cur-TF gel delivered curcumin to the arthritic dermal tissue through a topical route and demonstrated promising therapeutic efficacy by significantly alleviating complete Freud's adjuvant (CFA)-induced arthritis.

Valorization of khat (Catha edulis) waste for the production of cellulose fibers and nanocrystals

Cellulose fibers (C40 and C80) were extracted from khat (Catha edulis) waste (KW) with chlorine-free process using 40% formic acid/40% acetic acid (C40), and 80% formic acid/80% acetic acid (C80) at the pretreatment stage, followed by further delignification and bleaching stages. Cellulose nanocrystals (CNCs40 and CNCs80) were then isolated from C40 and C80 with sulfuric acid hydrolysis, respectively. Thus, the current study aims to isolate cellulose fibers and CNCs from KW as alternative source. The KW, cellulose fibers, and CNCs were investigated for yield, chemical composition, functionality, crystallinity, morphology, and thermal stability. CNCs were also evaluated for colloidal stability, particle size, and their influence on in vitro diclofenac sodium release from gel formulations preliminarily. The FTIR spectra analysis showed the removal of most hemicellulose and lignin from the cellulose fibers. The XRD results indicated that chemical pretreatments and acid hydrolysis significantly increased the crystallinity of cellulose fibers and CNCs. The cellulose fibers and CNCs exhibited Cellulose Iβ crystalline lattice. TEM analysis revealed formation of needle-shaped nanoscale rods (length: 101.55-162.96 nm; aspect ratio: 12.84-22.73). The hydrodynamic size, polydispersity index, and zeta potential of the CNCS ranged from 222.8-362.8 nm; 0.297-0.461, and -45.7 to -75.3 mV, respectively. CNCs40 exhibited superior properties to CNCs80 in terms of aspect ratio, and colloidal and thermal stability. Gel formulations containing high proportion of CNCs sustained diclofenac sodium release (< 50%/cm2) over 12 h. This study suggests that cellulose fibers and nanocrystals can be successfully obtained from abundant and unexploited source, KW for value-added industrial applications.

Rosuvastatin calcium-based novel nanocubic vesicles capped with silver nanoparticles-loaded hydrogel for wound healing management: optimization employing Box-Behnken design: in vitro and in vivo assessment

Chronic wounds are a serious problem that could cause severe morbidity and even death. The ability of statins including rosuvastatin calcium (RVS) to enhance wound healing was well reported. However, RVS is poorly soluble and has low bioavailability. Thus, this study aimed to prepare and evaluate RVS-loaded nanocubics to enhance its skin performance. In addition, silver nanoparticles (AgNPs) exhibited potent antimicrobial activity, thus, the optimum RVS-loaded nanocubics was capped with AgNPs to evaluate its effect in wound management. Box-Behnken design was adopted to prepare RVS nanocubics. The design investigated the effect of lecithin, poloxamer 407 concentrations and hydration time on vesicle size, zeta potential (ZP), entrapment efficiency (EE%) and in vitro drug release%. Optimum formulation capped with AgNPs was incorporated into a gel base and examined for wound healing efficiency using different pharmacological tests in rats. Nanocubics have shown a mean diameter between 167.2 ± 7.8 and 408 ± 18.4 nm, ZP values ranging from -20.9 ± 1.9 to -53.5 ± 4 mV, EE% equivocated between 31.6 ± 1.4 and 94.4 ± 8.6 and drug release after 12 h between 17.9 ± 1.9 and 68.0 ± 4.0%. The histopathological studies and serum tumour necrosis factor alpha (TNF-α) and interleukin-1β (IL-1β) levels confirmed the greater efficacy of RVS nanocubics capped with AgNPs gel in wound healing when compared with gentamicin ointment. RVS-loaded nanocubic vesicles and AgNPs-loaded hydrogel could be considered as a promising platform to enhance the wound healing and tissue repair processes.

Formulation and evaluation of simvastatin polymeric nanoparticles loaded in hydrogel for optimum wound healing purpose

Purpose

The aim of this study was to formulate a hydrogel loaded with polymeric nanoparticles (PoNPs) of simvastatin (SIM) for topical wound healing application.

Materials and methods

The SIM PoNPs were prepared by using the nanoprecipitation method to improve the drug solubility and skin permeation. Furthermore, drug content, solubility, particle size, surface charge, and transmission electron microscopy of the prepared PoNPs were evaluated. Then, the PoNPs were loaded on hydrogel, and physical characteristics, in vitro release, and ex vivo permeation of the hydrogel were evaluated. Finally, the prepared gel was applied on rat wounds, and a histopathological study was performed.

Results

The results showed that the drug content in the PoNPs was 86.4%. The PoNPs were spherical in shape with a smooth surface and a uniform size distribution. The particle size was 268.4±2.6, polydispersity index was ≤0.302, and zeta potential was −33±1.67 mV. The hydrogel loaded with SIM PoNPs was homogenous, and the pH was accepted and compatible with the skin. Moreover, the viscosity and spreadability assured its ease of application. The drug content was 97.25±0.02%. Furthermore, about 81% of SIM was released within 24 hours, while in the ex vivo permeation study 69.19% of SIM passed through the skin after 24 hours. Finally, the histopathological studies confirmed the efficacy of the SIM PoNPs-loaded hydrogel in wound healing due to the formation of the normal epithelial layer on day 11 after wound creation.

Conclusion

The hydrogel loaded with SIM PoNPs showed a good efficacy in accelerating the healing of the rat wound with complete epithelialization and minimal inflammatory cell infiltration.