Impact of Formulation and Microneedle Length on Transdermal Metronidazole Permeation through Microneedle-Treated Skin.

OBJECTIVE: This study aimed to determine the impact of formulation (gel vs cream) and microneedle characteristics (length, number) on permeation of metronidazole through excised microneedle-treated skin. The long-term goal is to apply these results towards a pharmacokinetic study in human subjects with diverse skin types, using in vitro flux data to determine dosing conditions and ultimately establish in vitro-in vivo correlations. METHODS: Metronidazole release from 0.75% gel and cream was quantified with flow-through diffusion cells, using a cellulose membrane. Excised porcine skin was treated with stainless steel microneedles (500 or 800 µm length), to create 50 or 100 micropores. Metronidazole gel or cream was applied to microneedle-treated skin and replaced every 48 h for up to 7 days. Metronidazole permeation was quantified using HPLC. Intact skin (no microneedle treatment) served as controls. RESULTS: Metronidazole release was faster from the gel vs cream. At 7 days there was no difference between gel vs cream in total metronidazole permeated through intact skin. For both formulations, metronidazole permeation was significantly higher (vs intact skin) following microneedle application, regardless of microneedle length or micropore number. Increasing microneedle length and micropore number enhanced MTZ permeation multiple fold for both gel and cream. The greatest enhancement in total permeation for both formulations was achieved with the 800 µm MN, 100 micropore condition. CONCLUSIONS: Formulation and microneedle conditions both impacted metronidazole permeation. These data will be used to estimate in vivo serum concentrations after applying metronidazole to microneedle-treated skin in humans.

Micropore Closure Rates following Microneedle Application at Various Anatomical Sites in Healthy Human Subjects.

INTRODUCTION: The continuous availability of open micropores is crucial for a successful microneedle (MN) drug delivery strategy. However, micropore lifetime depends on intrinsic skin functional and anatomical characteristics, which vary significantly at different anatomical sites. OBJECTIVE: This pilot study explored if differences exist in micropore closure timeframes at 3 anatomical sites - upper arm, volar forearm, and abdomen. METHODS: Healthy subjects (n = 35) self-identifying as Asian (n = 9), Bi-/multiracial (n = 2), Black (n = 9), Latino (n = 6), and White (n = 9) completed the study. The upper arm, volar forearm, and abdomen were treated with MNs; skin impedance and transepidermal water loss (TEWL) were measured at baseline and post-MN to confirm micropore formation. Impedance was measured for 3 days to evaluate micropore lifetime. Measurements of L*, which quantifies the skin lightness/darkness, were made using a tristimulus colorimeter. Micropore lifetime was determined by comparing baseline and post-MN impedance measurements, and micropore closure half-life was predicted using mathematical modeling. RESULTS: Post-MN increase in TEWL and decrease in impedance were significant (p < 0.05), confirming successful micropore formation at all anatomical sites. When data were analyzed according to subject self-identified racial/ethnic groups, the mean micropore closure time at the abdomen (63.09 ± 13.13 h) was longer than the upper arm (60.34 ± 14.69 h) and volar forearm (58.29 ± 16.76 h). The predicted micropore closure half-life at anatomical sites was the abdomen (25.86 ± 14.96 h) ≈ upper arm (23.69 ± 13.67 h) > volar forearm (20.2 ± 11.99 h). Differences were not statistically significant between groups. Objective categorization by L* showed that the darker skin may be associated with longer micropore closure time at the abdomen site. CONCLUSIONS: Our results suggest that anatomical site of application may not be a source of significant variability in micropore closure time. These findings may help reduce the number of physiological parameters that need to be explicitly considered when developing drug products to support MN-assisted drug delivery strategies.

Monochrome computer vision for detecting common external defects of mango.

Lack of rapid, non-destructive, and precision sorting and grading automatic tools for quality and safety assurance of mango fruit, in India, limits its share in the global market (< 1%) despite being the world's largest producer. External defects on the surface of mango fruit are very common and a major cause of quality deterioration as well as degradation of market value. The goal of this work is, thus, to develop a computer vision system for defect detection of mangoes using monochrome cameras and to check its potential for detecting the defect. Considering the above facts an algorithm was developed and its performance was evaluated based on accuracy, efficiency, and average inspection time. The average accuracy and efficiency of the developed algorithm for defect detection was obtained as 88.75% and 97.88%, respectively. Monochrome computer vision systems are very successful and have great potential to detect various common external defects such as a black lesions, mechanical damage, etc. SUPPLEMENTARY INFORMATION: The online version of this article (10.1007/s13197-020-04939-9) contains supplementary material, which is available to authorized users.

Antibiofilm Potential of Silver Sulfadiazine-Loaded Nanoparticle Formulations: A Study on the Effect of DNase-I on Microbial Biofilm and Wound Healing Activity.

Biofilm resistance is one of the severe complications associated with chronic wound infections, which impose extreme microbial tolerance against antibiotic therapy. Interestingly, deoxyribonuclease-I (DNase-I) has been empirically proved to be efficacious in improving the antibiotic susceptibility against biofilm-associated infections. DNase-I hydrolyzes the extracellular DNA, a key component of the biofilm responsible for the cell adhesion and strength. Moreover, silver sulfadiazine, a frontline therapy in burn wound infections, exhibits delayed wound healing due to fibroblast toxicity. In this study, a chitosan gel loaded with solid lipid nanoparticles of silver sulfadiazine (SSD-SLNs) and supplemented with DNase-I has been developed to reduce the fibroblast cytotoxicity and overcome the biofilm-imposed resistance. The extensive optimization using the Box-Behnken design (BBD) resulted in the formation of SSD-SLNs with a smooth surface as confirmed by scanning electron microscopy and controlled release (83%) for up to 24 h. The compatibility between the SSD and other formulation excipients was confirmed by Fourier transform infrared, differential scanning calorimetry, and powder X-ray diffraction studies. Developed SSD-SLNs in combination with DNase-I inhibited around 96.8% of biofilm of Pseudomonas aeruginosa as compared to SSD with DNase-I (82.9%). In line with our hypothesis, SSD-SLNs were found to be less toxic (cell viability 90.3 ± 3.8% at 100 µg/mL) in comparison with SSD (Cell viability 76.9 ± 4.2%) against human dermal fibroblast cell line. Eventually, the results of the in vivo wound healing study showed complete wound healing after 21 days' treatment with SSD-SLNs along with DNase-I, whereas marketed formulations SSD and SSD-LSNs showed incomplete healing after 21 days. Data in hand suggest that the combination of SSD-SLNs with DNase-I is an effective treatment strategy against the biofilm-associated wound infections and accelerates wound healing.

Melatonin and its ubiquitous anticancer effects.

Melatonin (N-acetyl-5-methoxy-tryptamine), which is generally considered as pleiotropic and multitasking molecule, secretes from pineal gland at night under normal light or dark conditions. Apart from circadian regulations, Melatonin also has antioxidant, anti-ageing, immunomodulation and anticancer properties. From the epidemiological research, it was postulated that Melatonin has significant apoptotic, angiogenic, oncostatic and anti-proliferative effects on various oncological cells. In this review, the underlying anticancer mechanisms of Melatonin such as stimulation of apoptosis, Melatonin receptors (MT1 and MT2) stimulation, paro-survival signal regulation, the hindering of angiogenesis, epigenetic alteration and metastasis have been discussed with recent findings. The Melatonin utilization as an adjuvant with chemotherapeutic drugs for the reinforcement of therapeutic effects was also discussed. This review precisely emphasizes the anticancer effect of Melatonin on various cancer cells. This review exemplifies the epidemiology and anticancer efficiency of Melatonin with prior attention to the mechanisms of actions.

Potential of reflected UV imaging technique for detection of defects on the surface area of mango.

Surface defects such as mechanical damage, black lesion, latex stains and shriveling of mango fruit are very common and responsible for lowering of market prices as well as postharvest losses. Current research, thus, focused on the study of reflected ultraviolet imaging (UV) technique, its potential of detecting defected mangoes and to develop a computer vision system which could find the reflected area on injured or defected mango's surface. The visual visualization of the bruised areas was noticed different when viewed under 15 W fluorescent UV tube (100-400 nm) light by UV camera. Hidden defects on fruit's surface detected just after the image acquisition by UV camera and brightness enhancement. Defected or injured surface of mangoes recognized easily by reflected UV imaging at 400 nm band-pass filter. The seriousness of injuries which were not detected by RGB color camera, detected by reflected UV imaging technique exactly.

Heat pump assisted drying of agricultural produce-an overview.

This review paper included the recent progress made in heat pump assisted drying, its principle, mechanism and efficiency, type and its application for drying of agricultural produce. Heat pump assisted drying provides a controllable drying environment (temperature and humidity) for better products quality at low energy consumption. It has remarkable future prospects and revolutionaries ability. The heat pump system consists of an expansion valve, two heat exchangers (evaporator and condenser), and a compressor, which are connected by using copper tubes. In this paper we also provided a review discussion on different type of heat pump assisted drying system ready for remarkable and commercial use in different type of food industries. Here we also have given some major advantage and disadvantage of heat pump assisted drying.

Machine vision system: a tool for quality inspection of food and agricultural products.

Quality inspection of food and agricultural produce are difficult and labor intensive. Simultaneously, with increased expectations for food products of high quality and safety standards, the need for accurate, fast and objective quality determination of these characteristics in food products continues to grow. However, these operations generally in India are manual which is costly as well as unreliable because human decision in identifying quality factors such as appearance, flavor, nutrient, texture, etc., is inconsistent, subjective and slow. Machine vision provides one alternative for an automated, non-destructive and cost-effective technique to accomplish these requirements. This inspection approach based on image analysis and processing has found a variety of different applications in the food industry. Considerable research has highlighted its potential for the inspection and grading of fruits and vegetables, grain quality and characteristic examination and quality evaluation of other food products like bakery products, pizza, cheese, and noodles etc. The objective of this paper is to provide in depth introduction of machine vision system, its components and recent work reported on food and agricultural produce.

Gemcitabine cationic polymeric nanoparticles against ovarian cancer: formulation, characterization, and targeted drug delivery.

This study focused on gemcitabine (GTB) delivery of cationic polymeric nanoparticles to treat ovarian cancer in order to promote effective localized delivery and drug retention during biological discharge. To begin, four GTB-loaded polymer nanoparticles were prepared: chitosan nanoparticles (CS-NPs), polysarcosin nanoparticles (PSar-NPs), poly-l-lysine & polysarcosin nanoparticles (PLL-PSar-NPs), and chitosan & polysarcosin nanoparticles (CS-PSar-NPs). Based on preliminary particle size, zeta potential, encapsulation efficiency, DSC, surface morphology, release profiling, and cellular internalization studies using rhodamine 123 and Nile red fluorescent markers, it was hypothesized that CS-PSar-NPs could be the best cationic formulation with strong biocompatibility and anticancer activity against the OVCAR-8 ovarian cancer cell line. To improve effective targeting, cellular penetration, and in vitro cytotoxicity, epidermal growth factor receptor variation III (EGFRvIII) is attached over all four polymeric nanoparticles. Confocal imaging revealed that EGFRvIII-conjugated cationic GTB polymeric nanoparticles had a greater cellular uptake and double internalization capabilities than unconjugated nanoparticles, as well as time-dependent cell entrance. GTB and EGFRvIII-conjugated polymer nanoparticles would have a stronger potential to infiltrate ovarian cancer cells during the first hour of incubation. According to TEM and FTIR findings, EGFRvIII conjugation across the non-target CS-PSar-NP surface was successful, making CS-PSar-NPS-EGFRvIII more target-specific and thus a safer drug delivery candidate for ovarian cancer treatment.HighlightsGTB loaded non-target CS-PSar-NPs & active targeted CS-PSar-NPs-EGFRvII developed.SEM, AFM, DSC, particle size, zeta potential, internalization performed for CS-PSar-NPs.MTT & CLSM study confirmed CS-PSar-NPS-EGFRvII was binding specific to OVCAR-8 cellsFabrication of EGFRvII over nanoparticles confirmed by TEM.CS-PSar-NPS-EGFRvII safer candidate for ovarian cancer.

Anacardic acid encapsulated solid lipid nanoparticles for Staphylococcus aureus biofilm therapy: chitosan and DNase coating improves antimicrobial activity.

Biofilm mediated bacterial infections are the key factors in the progression of infectious diseases due to the evolution of antimicrobial resistance. Traditional therapy involving antibiotics is not adequate enough for treatment of such infections due to the increased resistance triggered by biofilm. To overcome this challenge, we developed anacardic acid (Ana) loaded solid lipid nanoparticles (SLNs), further coated with chitosan and DNase (Ana-SLNs-CH-DNase). The DNase coating was hypothesized to degrade the e-DNA, while chitosan was coated to yield positively charged SLNs with additional adhesion to biofilms. The SLNs were developed using homogenization method and further evaluated for particle size, polydispersity index, zeta potential, and entrapment efficiency. Drug excipient compatibility was confirmed by using FT-IR study, while encapsulation of Ana in SLNs was confirmed by X-ray diffraction study. The SLNs demonstrated sustained release for up to 24 h and excellent stability at room temperature for up to 3 months. The developed SLNs were found non-toxic against human immortalized keratinocyte (HaCaT) cells while demonstrated remarkably higher antimicrobial efficacy against Staphylococcus aureus. Excellent effect of the developed SLNs on minimum biofilm inhibition concentration and minimum biofilm eradication concentration further confirmed the superiority of the developed formulation strategy. A significant (p < 0.05) reduction in biofilm thickness and biomass, as confirmed by confocal laser scanning microscopy, was observed in the case of developed SLNs in comparison with control. Cumulatively, the results suggest the enhanced efficacy of the developed formulation strategy to overcome the biofilm-mediated antimicrobial resistance. Graphical abstract.

Gold liposomes for brain-targeted drug delivery: Formulation and brain distribution kinetics.

This work was aimed to formulate transferrin (Tf) receptor targeted gold based theranostic liposomes which contain both docetaxel (DCX) and glutathione reduced gold nanoparticles (AuGSH) for brain-targeted drug delivery and imaging. AuGSH was prepared by reducing chloroauric acid salt using glutathione. The co-loading of DCX and AuGSH into liposomes was achieved by the solvent injection technique, and Tf was post-conjugated on the surface of the liposomes using carboxylated Vit-E TPGS (TPGS-COOH) as a linker. The liposomes were characterized for various parameters such as size, shape, surface charge, and drug release. The Tf receptor targeted gold liposomes were evaluated for the cytotoxicity by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) based colorimetric assay and in-vitro qualitative cellular uptake studies using confocal microscopy. The in-vivo site specific delivery of DCX was analyzed by the brain distribution study of DCX in comparison with marketed formulation (Docel™). A sustained drug release of about 70% was observed from liposomes in the span of 72 h. The in-vivo results demonstrated that targeted gold liposomes were able to deliver DCX into the brain by 3.70, 2.74 and 4.08-folds higher than Docel™ after 30, 120 and 240 min of the treatment, respectively. Besides, the results of these studies have suggested the feasibility of Tf decorated AuGSH and DCX co-loaded liposomes as a promising platform for targeted nano-theranostics.

An Ex Vivo Evaluation of Moxifloxacin Nanostructured Lipid Carrier Enriched In Situ Gel for Transcorneal Permeation on Goat Cornea.

The study was designed to fabricate the moxifloxacin nanostructured lipid carriers (MOX-NLCs) loaded in situ gel for opthalmic application to improve the corneal permeation and retention and also subside the toxic effect associated with intracameral injection of moxifloxacin in endophthalmitis treatment. Initially, Box-Behnken design was used to optimize the various factors significantly affecting the final formulation attributes. MOX-NLCs with particle size 232.1 ± 9.2 nm, polydispersity index 0.247 ± 0.031, zeta potential -16.3 ± 1.6 mV, entrapment efficiency 63.1 ± 2.4%, and spherical shape was achieved. The optimized MOX-NLCs demonstrated the Higuchi release kinetics with highest regression coefficient. Besides this, FTIR, differential scanning calorimetry, and X-ray diffraction results suggested that MOX had excellent compatibility with excipients. Furthermore, the results of ex-vivo permeation study demonstrated 2-fold higher permeation (208.7 ± 17.6 µg), retention (37.26 ± 2.83 µg), and flux (9.57 ± 0.73 µg/cm2 h) compared with free MOX in situ gel. In addition, MOX-NLCs exhibited normal corneal hydration and did not show any sign of structural damage to the corneal tissue as confirmed by histology. Therefore, the findings strongly suggest that MOX-NLCs in situ gel with higher permeation and retention can be a better alternative strategy to prevent and treat the endophthalmitis infection.

Alginate lyase immobilized chitosan nanoparticles of ciprofloxacin for the improved antimicrobial activity against the biofilm associated mucoid P. aeruginosa infection in cystic fibrosis.

Dense colonization of mucoid Pseudomonas aeruginosa within the self-secreted extracellular matrix (mainly alginate), called biofilm, is a principal reason for the failure of antimicrobial therapy in cystic fibrotic patients. Alginate is a key component in the biofilm of mucoid P. aeruginosa and responsible for surface adhesion and stabilization of biofilm. To overcome this problem, alginate lyase functionalized chitosan nanoparticles of ciprofloxacin were developed for the effective treatment of P. aeruginosa infection in cystic fibrosis patients. The developed nanoparticles were found to have desired quality attributes and demonstrated sustained release following the Higuchi release kinetics. Drug compatibility with the chitosan was confirmed by FTIR while powder X-ray diffraction analysis confirmed the entrapment of drug within the nanoparticle matrix. Lactose adsorbed NPs showed promising aerodynamic property. Nanoparticles showed prolonged MIC and significant reduction in biofilm aggregation and formation in planktonic bacterial suspension. Nanoparticles exhibited significantly higher inhibitory effect against biofilm of P. aeruginosa and reduced the biomass, thickness and density confirmed by confocal microscopy. Furthermore, developed nanoparticles were haemocompatible and did not exhibit any toxicity in vitro MTT assay and in vivo on lungs male Wistar rats. The data in hand collectively suggest the proposed strategy a better alternative for the effective treatment of cystic fibrosis infections.