Evaluation of photodynamic activity, photostability and in vitro drug release of zinc phthalocyanine-loaded nanocapsules

Efficiency of the photodynamic therapy on viability of Streptococcus mutans in the oral cavity using chitosan nanoparticles: an in vitro study

PURPOSE

This study aimed to investigate the efficiency of antimicrobial photodynamic therapy (aPDT) on Streptococcus mutans biofilm in the oral cavity using the photosensitizer chloroaluminum phthalocyanine encapsulated in chitosan nanoparticles (ClAlPc/Ch) at three preirradiation times.

METHODS

Biofilms of Streptococcus mutans strains (ATCC 25,175) were cultivated on bovine tooth blocks and exposed to a 10% sucrose solution three times a day for 1 min over three consecutive days. The samples were randomly distributed into five treatment groups (n = 5): (I) aPDT with ClAlPc/Ch with a preirradiation time of 5 min (F5), (II) aPDT with ClAlPc/Ch with a preirradiation time of 15 min (F15), (III) aPDT with ClAlPc/Ch with a preirradiation time of 30 min (F30), (IV) 0.12% chlorhexidine digluconate (CHX), and (V) 0.9% saline solution (NaCl). After treatment, the S. mutans biofilms formed on each specimen were collected to determine the number of viable bacteria (colony-forming units (CFU)/mL). Data were analyzed for normality using the Shapiro-Wilk test and the analysis of variance (ANOVA) and Tukey HSD tests to analyze the number of viable bacteria (α = 0.05).

RESULTS

The one-way ANOVA showed a difference between the groups (p = 0.0003), and the Tukey HSD posttest showed that CHX had the highest microbial reduction of S. mutans, not statistically different from the F5 and F15 groups, whereas the NaCl group had the lowest microbial reduction statistically similar to the F30 group.

CONCLUSION

The results demonstrate that aPDT mediated by ClAlPc/Ch when used at preirradiation times of 5-15 min can be an effective approach in controlling cariogenic biofilm of S. mutans, being an alternative to 0.12% CHX.

Phthalocyanine-based glucose-responsive nanocochleates for dynamic prevention of β-cell damage in diabetes

Phthalocyanine is a blue-colored macrocyclic compound with excellent anti-oxidant and lipid-peroxidation abilities due to its intermolecular π-π stacking structure. Antioxidants inhibit intracellular reactive oxygen species formation and decrease oxidation defense ability of the enzymes in diabetes management. The present study aimed to fabricate concanavalin A conjugated phthalocyanine-loaded cochleates (Formulation PhConA) as a glucose-sensitive lipidic system and estimate its efficacy in streptozotocin-induced male Sprague Dawley diabetic rats for 28 days. Thin-film hydration and trapping methods were used in the preparation of liposomes and cochleates, respectively, whereas the surface was modified for concanavalin A conjugation using EDAC: NHS (1:1). Formulation PhConA with rod-shaped structures showed particle size of 415.7 ± 0.46 nm, PdI value of 0.435 ± 0.09, encapsulation efficiency of 85.64 ± 0.34%, and 84.55 ± 0.29% release of phthalocyanine for 56 h. The circular dichroism study displayed a slight deviation after the conjugation effect of concanavalin A to cochleates. The in-vivo studies of the formulation PhConA improved the blood glucose levels along with defensive effect on the liver to overcome the hyperlipidemic effect. The rigid structure of cochleates prolongs the drug elimination from systemic circulation and extends its effect for a longer duration by decreasing the blood glucose level. Thus, the glucose-sensitive formulation PhConA showed significant improvement in diabetic rats within the period of 28 days by improving the oxidative defense and protecting the pancreatic β-cells.

Theoretical study of C6F5-corrole molecules functionalized with aromatic groups for Photodynamic Therapy

The singlet oxygen generation by electronically excited molecules in photodynamic therapy (PDT) requires light absorption within a specific wavelength window, and a subsequent intersystem crossing transition to a triplet excited state that is, at least, 0.98 eV higher in energy than the singlet ground state. Tetrapyrrolic macrocycles, such as porphyrin and corrole, have been widely used in oxygen singlet generation for PDT. Suitable functionalization can potentialize these macrocycles as photosensitizers. In this contribution, we use Density Functional Theory (DFT) calculations to determine the structural, electronic and spectroscopic properties of corrole macrocycles bound to different polycyclic aromatic groups in the gas phase, dichloromethane, and water. We also calculate the spin-orbit coupling (SOC) matrix elements of the intersystem crossing channels involving the first excited singlet states and excited triplet states. The results for optical absorption show that the threshold wavelength for optical absorption increases with the polarity of the environment and the number of aromatic rings of the ligands, whereas the oscillator strengths increase with the polarity of the environment but decrease with the number of aromatic rings. It is verified that the triplet excited states involved in the intersystem crossing transitions satisfy the energy requirement for the oxygen singlet generation. The magnitude of spin-orbit coupling (SOC) matrix elements associated with the intersystem crossing are also seen to be dependent on the environment involving the corrole molecules, and on the number of aromatic rings of the ligands connected to the corrole. Further, the binding of the functionalized corrole molecules with biomolecules as the calf thymus DNA and human serum albumin is studied and characterized through molecular docking. These results show that the corrole macrocycles, suitably functionalized with polycyclic aromatic groups, fulfill several criteria to be considered as good PDT photosensitizers.

Hydrophobization of a TIP60 Protein Nanocage for the Encapsulation of Hydrophobic Compounds

Encapsulation of hydrophobic molecules in protein-based nanocages is a promising approach for dispersing these molecules in water. Here, we report a chemical modification approach to produce a protein nanocage with a hydrophobic interior surface based on our previously developed nanocage, TIP60. The large pores of TIP60 act as tunnels for small molecules, allowing modification of the interior surface by hydrophobic compounds without nanocage disassembly. We used four different hydrophobic compounds for modification. The largest modification group tested, pyrene, resulted in a modified TIP60 that could encapsulate aromatic photosensitizer zinc phthalocyanine (ZnPC) more efficiently than the other modification compounds. The encapsulated ZnPC generated singlet oxygen upon light activation in the aqueous phase, whereas ZnPC alone formed inert aggregates under the same experimental conditions. Given that chemical modification allows a wider diversity of modifications than mutagenesis, this approach could be used to develop more suitable nanocages for encapsulating hydrophobic molecules of interest.

A hypoxia responsive silicon phthalocyanine containing naphthquinone axial ligands for photodynamic therapy activity

A liposome loaded‑silicon (IV) phthalocyanine (SiPc) containing naphthoquinone axial ligands as hypoxia-responsive a prodrug-like moieties (Prodrug-SiPc), is herein reported. With the help of computational methods, this study assessed the photophysical, photochemical and electrochemical redox properties of the Prodrug-SiPc to elucidate the relationship between material structure and properties. The attachment of the axial quinoid moieties endowed the Prodrug-SiPc with Type I/II photochemical and prodrug-like properties. Following liposomal encapsulation, the therapeutic efficacy of Prodrug-SiPc-liposomes was investigated against Michigan Cancer Foundation-7 (MCF-7) and Henrietta Lacks (Hela) cancer cells as in vitro cancer models and revealed that the as-synthesized Prodrug-SiPc-liposomes are potential photodynamic therapy (PDT) drug candidates. The Prodrug-SiPc-liposome takes full advantage of the hypoxic microenvironment of tumors - a side effect PDT - to trigger therapy, resulting in significantly enhanced efficacy compared to typical PDT. This work highlights the importance of multiple characteristics in designing new and effective photosensitizer candidates.

Development of New Natural Lipid-Based Nanoparticles Loaded with Aluminum-Phthalocyanine for Photodynamic Therapy against Melanoma

Photodynamic therapy (PDT) mediated by photosensitizers loaded in nanostructures as solid lipid nanoparticles has been pinpointed as an effective and safe treatment against different skin cancers. Amazon butters have an interesting lipid composition when it comes to forming solid lipid nanoparticles (SLN). In the present report, a new third-generation photosensitizing system consisting of aluminum-phthalocyanine associated with Amazon butter-based solid lipid nanoparticles (SLN-AlPc) is described. The SLN was developed using murumuru butter, and a monodisperse population of nanodroplets with a hydrodynamic diameter of approximately 40 nm was obtained. The study of the permeation of these AlPc did not permeate the analyzed skin, but when incorporated into the system, SLN-AlPc allowed permeation of almost 100% with 8 h of contact. It must be emphasized that SLN-AlPc was efficient for carrying aluminum-phthalocyanine photosensitizers and exhibited no toxicity in the dark. Photoactivated SLN-AlPc exhibited a 50% cytotoxicity concentration (IC₅₀) of 19.62 nM when applied to B16-F10 monolayers, and the type of death caused by the treatment was apoptosis. The exposed phospholipid phosphatidylserine was identified, and the treatment triggered a high expression of Caspase 3. A stable Amazon butter-based SLN-AlPc formulation was developed, which exhibits strong in vitro photodynamic activity on melanoma cells.

An Update on Photodynamic Therapy of Psoriasis—Current Strategies and Nanotechnology as a Future Perspective

Psoriasis (PS) is an immune-mediated skin disease with substantial negative effects on patient quality of life. Despite significant progress in the development of novel treatment options over the past few decades, a high percentage of patients with psoriasis remain undertreated and require new medications with superior long-term efficacy and safety. One of the most promising treatment options against psoriatic lesions is a form of phototherapy known as photodynamic therapy (PDT), which involves either the systemic or local application of a cell-targeting photosensitizing compound, followed by selective illumination of the lesion with visible light. However, the effectiveness of clinically incorporated photosensitizers in psoriasis treatment is limited, and adverse effects such as pain or burning sensations are frequently reported. In this study, we performed a literature review and attempted to provide a pooled estimate of the efficacy and short-term safety of targeted PDT in the treatment of psoriasis. Despite some encouraging results, PDT remains clinically underutilized. This highlights the need for further studies that will aim to evaluate the efficacy of a wider spectrum of photosensitizers and the potential of nanotechnology in psoriasis treatment.

Pharmaceutical Nanotechnology Applied to Phthalocyanines for the Promotion of the Antimicrobial Photodynamic Therapy: A Literature Review

Phthalocyanines are photosensitizers activated by light at a specific wavelength in the presence of oxygen and act topically through the production of Reactive Oxygen Species, which simultaneously attack several biomolecular targets in the pathogen agent and, therefore, have multiple and variable action sites. This nonspecific action site delineates the conventional resistance mechanisms. Antimicrobial Photodynamic Therapy (aPDT) is safe, easy to implement and, unlike conventional agents, the activity spectrum of photoantimicrobials. This work is a systematic review of the literature based on nanocarriers containing phthalocyanines in aPDT against bacteria, fungi, viruses, and protozoa. The search was performed in two different databases (MEDLINE/PubMed and Web of Science) between 2011 and May 2021. Nanocarriers often improve the action or are equivalent to free drugs, but their use allows substituting the organic solvent in the case of hydrophobic phthalocyanines, allowing for a safer application of aPDT with the possibility of prolonged release. In the case of hydrophilic phthalocyanines, they would allow for nonspecific site delivery with a possibility of cellular internalization. A single infectious lesion can have multiple microorganisms, and PDT with phthalocyanines is an interesting treatment given its ample spectrum of action. It is possible to highlight the upconversion nanosystems, which allow for the activation of phthalocyanine in deeper tissues by using longer wavelengths, as a system that has not yet been studied, but which could provide treatment solutions. The use of nanocarriers containing phthalocyanines requires more studies in animal models and clinical studies to establish the use of aPDT in humans.

Design and Characterization of Maltoheptaose-b-Polystyrene Nanoparticles, as a Potential New Nanocarrier for Oral Delivery of Tamoxifen

Tamoxifen citrate (TMC), a non-steroidal antiestrogen drug used for the treatment of breast cancer, was loaded in a block copolymer of maltoheptaose-b-polystyrene (MH-b-PS) nanoparticles, a potential drug delivery system to optimize oral chemotherapy. The nanoparticles were obtained from self-assembly of MH-b-PS using the standard and reverse nanoprecipitation methods. The MH-b-PS@TMC nanoparticles were characterized by their physicochemical properties, morphology, drug loading and encapsulation efficiency, and release kinetic profile in simulated intestinal fluid (pH 7.4). Finally, their cytotoxicity towards the human breast carcinoma MCF-7 cell line was assessed. The standard nanoprecipitation method proved to be more efficient than reverse nanoprecipitation to produce nanoparticles with small size and narrow particle size distribution. Moreover, tamoxifen-loaded nanoparticles displayed spherical morphology, a positive zeta potential and high drug content (238.6 ± 6.8 µg mL-1) and encapsulation efficiency (80.9 ± 0.4 %). In vitro drug release kinetics showed a burst release at early time points, followed by a sustained release profile controlled by diffusion. MH-b-PS@TMC nanoparticles showed higher cytotoxicity towards MCF-7 cells than free tamoxifen citrate, confirming their effectiveness as a delivery system for administration of lipophilic anticancer drugs.

Zinc pthalocyanine loaded poly (lactic acid) nanoparticles by double emulsion methodology for photodynamic therapy against 9 L/LacZ gliosarcoma cells

Development delivery systems, such as nanoparticles, represent a growing area in biomedical research. Nanoparticles (NP) were prepared using a double-emulsion method to load zinc(II) phthalocyanine (ZnPc). NP were obtained using poly (lactic acid) (PLA). ZnPc is a second generation of photosensitizer used in photodynamic therapy (PDT). ZnPc loaded PLA nanoparticles (NPLA-ZnPc) were prepared by double-emulsion method, characterized and available in cellular culture. The mean nanoparticle size presented particle size was 384.7 ± 84.2 nm with polydispersity index (PDI) of 0.150 ± 0.015, and the encapsulation efficiency was of 83%. The nanoparticle formulations presented negative zeta potential values (-27.5 ± 1.0 mV), explaining their colloidal stability. ZnPc loaded nanoparticles maintain its photophysical behavior after encapsulation. Photosensitizer release from nanoparticles was sustained over 168 h with a biphasic ZnPc release profile. An in vitro phototoxic effect in range of 80% was observed in 9 L/LacZ gliosarcoma cells at laser light doses (10 J cm^-2) with 3.0 µg mL^-1 of NPLA-ZnPc. All the physical-chemical, photophysical and photobiological measurements performed allow us to conclude that ZnPc loaded PLGA nanoparticles is a promising drug delivery system for PDT.

Application of Asymmetrical Flow Field-Flow Fractionation for Characterizing the Size and Drug Release Kinetics of Theranostic Lipid Nanovesicles

Liposome size and in vitro release of the active substance belong to critical quality attributes of liposomal carriers. Here, we apply asymmetric flow field-flow fractionation (AF4) to characterize theranostic liposomes prepared by thin lipid film hydration/extrusion or microfluidics. The vesicles' size was derived from multi-angle laser light scattering following fractionation (AF4) and compared to sizes derived from dynamic light scattering measurements. Additionally, we adapted a previously developed AF4 method to study zinc phthalocyanine (ZnPc) release/transfer from theranostic liposomes. To this end, theranostic liposomes were incubated with large acceptor liposomes serving as a sink (mimicking biological sinks) and were subsequently separated by AF4. During incubation, ZnPc was transferred from donor to acceptor fraction until reaching equilibrium. The process followed first-order kinetics with half-lives between 119.5-277.3 min, depending on the formulation. The release mechanism was postulated to represent a combination of Fickian diffusion and liposome relaxation. The rate constant of the transfer was proportional to the liposome size and inversely proportional to the ZnPc/POPC molar ratio. Our results confirm the usefulness of AF4 based method to study in vitro release/transfer of lipophilic payload, which may be useful to estimate the unwanted loss of drug from the liposomal carrier in vivo.

Recent Progress in Phthalocyanine-Polymeric Nanoparticle Delivery Systems for Cancer Photodynamic Therapy

This perspective article summarizes the last decade’s developments in the field of phthalocyanine (Pc)-polymeric nanoparticle (NP) delivery systems for cancer photodynamic therapy (PDT), including studies with at least in vitro data. Moreover, special attention will be paid to the various strategies for enhancing the behavior of Pc-polymeric NPs in PDT, underlining the great potential of this class of nanomaterials as advanced Pcs’ nanocarriers for cancer PDT. This review shows that there is still a lot of research to be done, opening the door to new and interesting nanodelivery systems.

Polymeric nanocapsules: A review on design and production methods for pharmaceutical purpose

Polymeric nanocapsules have extensive application potential in medical, biological, and pharmaceutical fields, and, therefore, much research has been dedicated to their production. Indeed, production protocols and the materials used are decisive for obtaining the desired nanocapsules characteristics and biological performance. In addition to that, several technological strategies have been developed in the last decade to improve processing techniques and form more valuable nanocapsules. This review provides a guide to current methods for developing polymeric nanocapsules, reporting aspects to be considered when choosing appropriate materials, and discussing different ways to produce nanocapsules for superior performances.

Synergic effects of ultrasound and ionic liquids on fluconazole emulsion

The aim of this work was to evaluate the influence of US on the properties of the fluconazole emulsions prepared using imidazolium-based ILs ([C_n C₁im]Br). The effects of the preparation method (mechanical stirring or US), US amplitude, alkyl chain length (of [C₁₂C₁im]Br or [C₁₆C₁im]Br), and IL concentration on the physicochemical properties were evaluated. Properties such as droplet size, span index, morphology, viscosity encapsulation efficiency, and drug release profile were determined. The results showed that US-prepared emulsions had a smaller droplet size and smaller polydispersity (Span) than those prepared by mechanical stirring. Additionally, the results showed that emulsions prepared with [C₁₆C₁im]Br and US had spherical shapes and increased stability compared to emulsions prepared by MS, and also depended on the IL concentration. The emulsion prepared by US at 40% amplitude had increased encapsulation efficiency. US provided a decrease in the viscosity of emulsions containing [C₁₂C₁im]Br; however, in general, all emulsions had viscosity close to that of water. Emulsions containing [C₁₆C₁im]Br had the lowest viscosities of all the emulsions. The emulsions containing the IL [C₁₆C₁im]Br had more controlled release and a lower cumulative percentage of drug release. The IL concentration required to prepare these emulsions was lower than the amount of conventional surfactant required, which highlights the potential synergic effects of ILs and US in preparing emulsions of hydrophobic drugs.

Photodynamic Therapy of Psoriasis Using Photosensitizers of Vegetable Origin

Psoriasis is an immune-mediated, chronic and recurrent inflammatory skin disease, prevalent worldwide, and represents an important burden in life quality of patients. The most common clinical variant is termed as psoriasis vulgaris or plaque psoriasis, which with an individualized and carefully monitored therapy can decrease the patients' morbidity and improving their life quality. The aim is to achieve disease control, minimize the adverse drug effects, and tailor the treatment to individual patient factors. Photodynamic therapy (PDT) is based on local or systemic administration of a non-toxic photosensitizer followed by irradiation with a particular wavelength to generate reactive oxygen species (ROS), mainly highly cytotoxic singlet oxygen (1O2). The generation of these species results in the attack to substrates involved in biological cycles causing necrosis and apoptosis of affected tissues. Photosensitizers are found in natural products and also obtained by partial syntheses from abundant natural starting compounds. They can be isolated at low cost and in large amounts from plants or algae. Therefore, this manuscript reviews the use of molecules from vegetal sources as photosensitizer agents for the PDT of psoriasis. Psoriasis pathogenesis, management and treatment were reviewed. PDT principles, fundamentals and utilization for the treatment of psoriasis were also discussed. Photosensitizers for PDT of psoriasis are also reviewed focusing on those from vegetal sources. Despite the PDT is utilized for the treatment of psoriasis, very little amount of photosensitizers from plant sources are utilized, such as chlorophyll derivatives and hypericin; however, other natural photosensitizers such as curcumin, could also be investigated. They could constitute a very important, safe and cheap alternative for the successful photodynamic treatment of psoriasis.

Conjugate of chitosan nanoparticles with chloroaluminium phthalocyanine: Synthesis, characterization and photoinactivation of Streptococcus mutans biofilm

BACKGROUND

Antimicrobial photodynamic therapy (aPDT) using chloroaluminium phthalocyanine (ClAlPc) has high oxidative power allowing for the control of biofilms, especially when the photosensitizer is administered in an appropriate release vehicle. This study aimed to develop/characterize the ClAlPc encapsulated in chitosan nanoparticles (CSNPs), and evaluate its antimicrobial properties against S. mutans biofilms.

METHODS

CSNPs were prepared by ion gelation, and characterization studies included particle size, polydispersion index (IPd), zeta potential, accelerated stability, absorption spectrum and ClAlPc quantification. The S. mutans biofilms were formed in bovine dentin blocks at 37 °C for 48 h under microaerophilic conditions. 8 μM ClAlPc was combined with a diode laser (InGaAlP) at 660 nm and 100 J/cm². The aPDT toxicity was verified by dark phototoxicity. The antimicrobial activity was verified by CFU/mL and biofilm was analyzed by scanning electron microscopy (SEM). The number of viable bacteria was analyzed by ANOVA and Tukey HSD tests (α = 0.05).

RESULTS

The characterization revealed that the ClAlPc nanoparticles were found in nanometer-scale with adequate photophysical and photochemical properties. The aPDT mediated by ClAlPc + CSNPs nanoconjugate showed a significant reduction in the viability of S. mutans (1log10 CFU/mL) compared to the negative control (PBS, p < 0.05). The aPDT mediated by ClAlPc was similar to PBS (p > 0.05). SEM revealed change in biofilm morphology following the treatment of bacteria with aPDT ClAlPc + CSNPs. Cells were arranged as single or in shorted chains. Irregular shapes of S. mutans were found.

CONCLUSION

ClAlPc nanoparticles are considered stable and aPDT mediated by ClAlPc + CSNPs nanoconjugate was effective against S. mutans biofilm.

Design of new protein drug delivery system (PDDS) with photoactive compounds as a potential application in the treatment of glioblastoma brain cancer

Glioblastoma multiforme (GBM) is an extremely aggressive malignant brain tumor. Despite advances in treatment modalities, it remains largely incurable. This unfavorable prognosis for GBM is at least partly due to the lack of a successful drug delivery system across the blood-brain barrier (BBB). The delivery of drugs through nanomedicines combined with less invasive alternative therapies represents an important hope for the future of these incurable brain tumors. Whey protein nanocarriers represent promising strategy for targeted drug delivery to tumor cells by enhancing the drug's bioavailability and distribution, and reducing the body's response towards drug resistance. They have been extensively studied to find new alternatives for capacity to encapsulate different drugs and no need for cross-linkers. In this study, we report for the first time the incorporation and administration of Aluminum phthalocyanine chloride (AlClPc)-loaded whey protein drug delivery system (AlClPc-PDDS) for the treatment of glioblastoma brain cancer. This system was designed and optimized (with the use of the spray drying technique) to obtain the required particle size (in the range of 100 to 300 nm), zeta potential and drug loading. Our results suggest that we have developed a drug delivery system from a low-cost raw material and preparation method that is capable of incorporating hydrophobic drugs which, in combination with irradiation, cause photodamage to neoplasic cells, working as an effective adjuvant treatment for malignant glioma.

Evaluation of photodynamic therapy and nuclear imaging potential of subphthalocyanine integrated TiO2 nanoparticles in mammary and cervical tumor cells

This study, subphthalocyanines (SubPc) and SubPc integrated TiO2 nanoparticles (SubPc-TiO[Formula: see text] were synthesized as novel photosensitizers. Their PDT effects were evaluated. Furthermore, nuclear imaging potential of [Formula: see text]I-labelled SubPc/SubPc-TiO2 were examined in mouse mammary carcinoma (EMT6) and cervix adenocarcinoma (HeLa) cell lines. The uptake results show that SubPc labelled with [Formula: see text]I radionuclide ([Formula: see text]I-SubPc) in EMT6 and HeLa cell lines was found to be approximately the same as in the WI38 cell line. However, the uptake values of SubPc-TiO2 labelled with [Formula: see text]I ([Formula: see text]I-SubPc-TiO[Formula: see text] in EMT6 and HeLa cell lines were determined to be two times higher than in the WI38 cell line. In other words, the target/non-target tissue ratio was identified as two in the EMT6 and HeLa cell lines. [Formula: see text]I-SubPc-TiO2 is promising for imaging or treatment of breast and cervix tumors. In vitro photodynamic therapy studies have shown that SubPc and SubPc-TiO2 are suitable agents for PDT. In addition, SubPc-TiO2 has higher phototoxicity than SubPc. As a future study, in vivo experiments will be held and performed in tumor-bearing nude mice.

Understanding the prospective of nano-formulations towards the treatment of psoriasis

Psoriasis is a consistently recurring, inflammatory, autoimmune disorder of the skin, affecting about 2-5% of the world population. Abundant therapeutic agents are accessible for the treatment of psoriasis. Nevertheless, none of them are entirely secure and effective to treat the disease without compromising patient compliance. Furthermore, already existing drugs are supposed to restrain the ailment and alleviate the sign and symptoms with no complete cure. However, they focus on restraining the disease and alleviating the symptoms without providing an absolute cure. Therefore there remains a vital challenge, to explore a new drug moiety or delivery system which could safely and effectively manage psoriasis without compromising patient compliance. Furthermore, conventional formulations offer reduced benefit/risk ratio of anti-psoriatic drugs, which limits the use of existing conventional formulations. Novel formulations based on nanocarriers are a promising prospect to overcome the limitation of conventional formulations by offering a reduction in dose, dosing frequency, dose-dependent, side effects with enhanced efficacy. Presently nano-formulations have gained widespread application for effective and safe treatment of psoriasis. The present review primarily focuses on conventional therapeutic strategy and recent advances in lipid-based, polymer-based and metallic nano-formulations of a variety of anti-psoriatic drugs. The practicability of various nanocarrier systems including liposomes, nanostructured lipid carriers, ethosomes, solid lipid nanoparticles, nanocapsules, micelles, dendrimers, gold nanoparticles and silver nanoparticles have been discussed in detail. The review also traces related patents to exemplify the role of various nanoparticles in psoriasis treatment. In a nutshell, nano-formulations remain established as a promising modality for treating psoriasis treatment as they propose better penetration, targeted delivery, enhanced safety, and efficacy.

Theranostic micelles combined with multiple strategies to effectively overcome multidrug resistance

AIM

To develop precise targeting and versatile Fe₃O₄@SiO₂-P123/PTX-ZnPc nanoparticles (FSP-PTX-ZnPc NPs) to reverse paclitaxel (PTX)-induced multidrug resistance in breast cancer.

MATERIALS & METHODS

PTX and zinc (II) phthalocyanine (ZnPc) co-loaded FSP-PTX-ZnPc NPs were designed. The resulting multifunctional NPs were evaluated systematically in vitro and in vivo, and the mechanism of drug-resistance reversal was investigated.

RESULTS

The NPs enhanced drug uptake in MCF-7/PDR cells by increasing drug solubility and impairing P-glycoprotein efflux. Additionally, magnetic targeting and enhanced permeation and retention (EPR) effect enhanced drug accumulation in tumor, facilitating the chemotherapeutic and photodynamic therapy effects. Moreover, FSP-PTX-ZnPc NPs could penetrate the blood-brain barrier, a desirable trait for brain disease therapy.

CONCLUSION

The multifunctional FSP-PTX-ZnPc NPs are an effective tool for overcoming drug resistance in breast cancer.

Evaluation of a combined emulsion process to encapsulate methylene blue into PLGA nanoparticles

The delivery of photosensitizer compounds using biodegradable nanoparticles could improve dosage, controlled release and its bioavailability.