Blends of cross-linked high amylose starch/pectin loaded with diclofenac

The contemplation of amylose for the delivery of ulcerogenic nonsteroidal anti-inflammatory drugs

This manuscript proposes an innovative approach to mitigate the gastrointestinal adversities linked with nonsteroidal anti-inflammatory drugs (NSAIDs) by exploiting amylose as a novel drug delivery carrier. The intrinsic attributes of V-amylose, such as its structural uniqueness, biocompatibility and biodegradability, as well as its capacity to form inclusion complexes with diverse drug molecules, are meticulously explored. Through a comprehensive physicochemical analysis of V-amylose and ulcerogenic NSAIDs, the plausibility of amylose as a protective carrier for ulcerogenic NSAIDs to gastrointestinal regions is elucidated. This review further discusses the potential therapeutic advantages of amylose-based drug delivery systems in the management of gastric ulcers. By providing controlled release kinetics and enhanced bioavailability, these systems offer promising prospects for the development of more effective ulcer therapies.

Production and characterization of starch-lignin based materials: A review

In their pristine state, starch and lignin are abundant and inexpensive natural polymers frequently considered green alternatives to oil-based and synthetic polymers. Despite their availability and owing to their physicochemical properties; starch and lignin are not often utilized in their pristine forms for high-performance applications. Generally, chemical and physical modifications transform them into starch- and lignin-based materials with broadened properties and functionality. In the last decade, the combination of starch and lignin for producing reinforced materials has gained significant attention. The reinforcing of starch matrices with lignin has received primary focus because of the enhanced water sensitivity, UV protection, and mechanical and thermal resistance that lignin introduces to starch-based materials. This review paper aims to assess starch-lignin materials' production and characterization technologies, highlighting their physicochemical properties, outcomes, challenges, and opportunities. First, this paper describes the current status, sources, and chemical modifications of lignin and starch. Next, the discussion is oriented toward starch-lignin materials and their production approaches, such as blends, composites, plasticized/crosslinked films, and coupled polymers. Special attention is given to the characterization methods of starch-lignin materials, focusing on their advantages, disadvantages, and expected outcomes. Finally, the challenges, opportunities, and future perspectives in developing starch-lignin materials, such as adhesives, coatings, films, and controlled delivery systems, are discussed.

Exploring the Drug-Loading and Release Ability of FucoPol Hydrogel Membranes

The polysaccharide FucoPol has recently been shown to yield hydrogel membranes (HMs) characterized by good mechanical properties, biocompatibility, and anti-inflammatory activity that render them promising biomaterials for use in the biomedical field. Subsequently to such findings, envisaging their development into novel delivery systems for topical applications, in this study, FucoPol HMs prepared by crosslinking the biopolymer with iron cations were loaded with caffeine or diclofenac sodium as model drugs. Two loading methods, namely diffusion and mixing, were applied to evaluate the FucoPol's HM drug-loading capacity and entrapment efficiency. The diffusion method led to a higher caffeine loading (101.9 ± 19.1 mg/g) in the HM1_DCAF membranes, while the mixing method resulted in a higher diclofenac sodium loading (82.3 ± 5.1 mg/g) in the HM1_DDS membranes. The HM1_DCAF membranes were characterized by increased mechanical and rheological parameters, such as their hardness (130.0 ± 5.3 kPa) and storage modulus (1014.9 ± 109.7 Pa), compared to the HM1_DDS membranes that exhibited lower values (7.3 ± 1.2 kPa and 19.8 ± 3.8 Pa, respectively), probably due to leaching occurring during the drug-loading process. The release profiles revealed a fast release of both APIs from the membranes loaded by diffusion, while a prolonged and sustained release was obtained from the membranes loaded by mixing. Moreover, for all API-loaded membranes, the release mechanism followed Fickian diffusion, with the release rate being essentially governed by the diffusion process. These findings, together with their previously shown biological properties, support the suitability of the developed FucoPol HMs to be used as platforms for the topical delivery of drugs.

Recent developments in natural biopolymer based drug delivery systems

Targeted delivery of drug molecules to diseased sites is a great challenge in pharmaceutical and biomedical sciences. Fabrication of drug delivery systems (DDS) to target and/or diagnose sick cells is an effective means to achieve good therapeutic results along with a minimal toxicological impact on healthy cells. Biopolymers are becoming an important class of materials owing to their biodegradability, good compatibility, non-toxicity, non-immunogenicity, and long blood circulation time and high drug loading ratio for both macros as well as micro-sized drug molecules. This review summarizes the recent trends in biopolymer-based DDS, forecasting their broad future clinical applications. Cellulose chitosan, starch, silk fibroins, collagen, albumin, gelatin, alginate, agar, proteins and peptides have shown potential applications in DDS. A range of synthetic techniques have been reported to design the DDS and are discussed in the current study which is being successfully employed in ocular, dental, transdermal and intranasal delivery systems. Different formulations of DDS are also overviewed in this review article along with synthesis techniques employed for designing the DDS. The possibility of these biopolymer applications points to a new route for creating unique DDS with enhanced therapeutic qualities for scaling up creative formulations up to the clinical level.

Fabrication of pH responsive hydrogel blends of chondroitin sulfate/pluronic F-127 for the controlled release of ketorolac: its characterization and acute oral toxicity study

OBJECTIVE

Ketorolac tromethamine (KT), selected as a model drug, is used in management of moderate to severe acute pain. It has a short half-life (∼5.5 h) and requires frequent dose administration when needed for longer period of time. In our current project, we designed pH responsive hydrogel blends of chondroitin sulfate/pluronic F-127 (CS/Pl) for the controlled release of ketorolac.

METHODS

Hydrogel blends were fabricated using free radical polymerization reaction technique utilizing different ratios of chondroitin sulfate (CS) (polymer) and pluronic F-127 (polymer), acrylic acid (monomer), N,N'-methyl-bisacrylamide (MBA) (cross-linker), initiator ammonium persulfate (APS) and tween-80 (surfactant). The fabricated hydrogel blends were studied and evaluated for pH responsiveness, swelling, water absorbency, in vitro drug release, and morphological characteristics such as SEM, XRD, FTIR, and TGA/DSC. Acute toxicity study was performed on rabbits.

RESULTS

Maximum swelling and water absorbency were shown by CS/Pl blends being significantly greater at 7.4 (basic pH) than in 1.2 (acidic pH). In vitro dissolution demonstrated pH responsive controlled KT release following zero order at higher pH (7.4) medium up to 36 h. FTIR studies confirmed the structures of our blends; SEM results showed porous framework; thermal studies revealed higher stability of hydrogels than the individual polymers; and XRD confirmed the nature of our blends. Toxicity study revealed the nontoxic nature of the hydrogel blends.

CONCLUSION

The prepared CS/Pl hydrogels demonstrated stimuli-controlled release with delivery of drug for prolonged period of time and thus can minimize dosing frequency, safe drug delivery, increased patient compliance and easiness.

Cytocompatible drug delivery hydrogels based on carboxymethylagarose/chitosan pH-responsive polyelectrolyte complexes

Several drugs are chemically unstable in the gastric environment and have low bioavailability restricted by intestinal absorption, which motivates the development of alternative routes for drug release, such as transdermal drug carriers for drug delivery to specific areas of the skin. Herein, novel polyelectrolyte complexes (PEC) consisting of carboxymethylagarose (CMA) and chitosan (CS) were prepared. pH-responsive CMA/CS hydrogels were obtained by mixing CMA and CS at various weight ratios. Swelling ratio was modulated by varying the CMA and CS weight ratio, and the highest swelling values were achieved for 2:1 wt% hydrogels at 25 °C and pH 6.0. PEC films were characterized by ATR-FTIR spectroscopy, TGA, DSC, and SEM. Results indicated that CMA and CS were successfully crosslinked by ionic complexation. As a model drug, diclofenac sodium (DS) was loaded in CMA/CS PECs. Association efficiency and loading capacity were ca. 69% and 79%, respectively, exhibiting 67% cumulative release after 72 h at 37 °C and pH 6.0 through Fickian diffusion mechanism. Viability assay of immortalized human keratinocyte (HaCat) cells showed ca. 100% survival in the presence of hydrogels and DS. Therefore, this work suggests that CMA/CS PECs can be applied as pH-responsive carriers for dermal drug delivery.

Preclinical Evaluation of Polymeric Nanocomposite Containing Pregabalin for Sustained Release as Potential Therapy for Neuropathic Pain

This study offers a novel oral pregabalin (PG)-loaded drug delivery system based on chitosan and hypromellose phthalate-based polymeric nanocomposite in order to treat neuropathic pain (PG-PN). PG-PN has a particle size of 432 ± 20 nm, a polydispersity index of 0.238 ± 0.001, a zeta potential of +19.0 ± 0.9 mV, a pH of 5.7 ± 0.06, and a spherical shape. Thermal and infrared spectroscopy confirmed nanocomposite generation. PG-PN pharmacokinetics was studied after a single oral dose in male Wistar rats. PG-PN showed greater distribution and clearance than free PG. The antinociceptive effect of PG-PN in neuropathic pain rats was tested by using the chronic constriction injury model. The parameter investigated was the mechanical nociceptive threshold measured by the von Frey filaments test; PG-PN showed a longer antinociceptive effect than free PG. The rota-rod and barbiturate sleep induction procedures were used to determine adverse effects; the criteria included motor deficit and sedative effects. PG-PN and free PG had plenty of motors. PG-PN exhibited a less sedative effect than free PG. By prolonging the antinociceptive effect and decreasing the unfavorable effects, polymeric nanocomposites with pregabalin have shown promise in treating neuropathic pain.

Effect of pectin and attapulgite filler on swelling, network parameters and controlled release of diltiazem hydrochloride from polyacrylic copolymer gel

Pectin grafted polyacrylic copolymer hydrogels were made by free radical crosslink copolymerization of acrylic acid (AA) and acrylamide (AM) in an aqueous solution of pectin. N'N-methylene bis acrylamide (MBA) was used as a crosslinker. During the polymerization reaction the attapulgite (APG) filler was also incorporated in situ into the network of the copolymer gel. Several filled hydrogels were prepared by varying the amount of pectin and APG filler. These hydrogels were characterized by FTIR, ¹³C NMR, XRD, TGA, SEM, mechanical properties, DMA, swelling, diffusion characteristics and network parameters. The release kinetics of a model drug diltiazem hydrochloride (DT) was studied with these hydrogels. The wt% of pectin, APG and MBA was optimized with a central composite design (CCD) model of response surface methodology (RSM) with equilibrium swelling ratio (ESR), drug adsorption (mg/100 mg gel) and drug release% in 16 h as response. Accordingly, the hydrogel prepared with 5:1 AA:AM molar ratio, 25 wt% monomer concentration, 1% each of initiator and MBA concentration, 18 wt% pectin and 2 wt% APG showed an optimized ESR of 17.75, drug loading of 27.58 and a drug release % of 92.5 in 16 h at a solution pH of 7.4.

Starch chemical modifications applied to drug delivery systems: From fundamentals to FDA-approved raw materials

Starch derivatives are versatile compounds that are widely used in the pharmaceutical industry. This article reviews the advances in the research on hydrophilic and hydrophobic starch derivatives used to develop drug delivery systems over the last ten years, specifically microparticles, nanoparticles, nanocrystals, hydrogels, and scaffolds using these materials. The fundamentals of drug delivery systems, regulatory aspects, and chemical modifications are also discussed, along with the synthesis of starch derivatives via oxidation, etherification, acid hydrolysis, esterification, and cross-linking. The chemical modification of starch as a means to overcome the challenges in obtaining solid dosage forms is also reviewed. In particular, dialdehyde starches are potential derivatives for direct drug attachment; carboxymethyl starches are used for drug encapsulation and release, giving rise to pH-sensitive devices through electrostatic interactions; and starch nanocrystals have high potential as hydrogel fillers to improve mechanical properties and control drug release through hydrophilic interactions. Starch esterification with alginate and acidic drugs could be very useful for site-specific, controlled release. Starch cross-linking with other biopolymers such as xanthan gum is promising for obtaining novel polyelectrolyte hydrogels with improved functional properties. Surface modification of starch nanoparticles by cross-linking and esterification reactions is a potential approach to obtain novel, smart solid dosages.

Morphology, structure, properties and applications of starch ghost: A review

Starch ghost, an insoluble structure of gelatinized starch, plays an important role in the applications of starch. In this review, we summarized the preparation, morphology, structure, properties and applications of starch ghost. The preparation steps of starch ghost include gelatinization, purification and preservation, and many factors influence the yield of starch ghost. The morphology and content of starch ghost can be influenced by many factors like starch resource and amylose content. Ghosts from non-waxy starches are composed of amylopectin with long branch-chains and amylose. These molecules cross-link to each other to reinforce the structure, and tend to form B-type double helix in ghosts from high-amylose starches. Some surface proteins that bind tightly to starch granules are also present in starch ghost. Protein and lipid are thought to have limited effects on the structural stability, but they make a big difference in the morphology of starch ghost. Starch ghost shows a different resistance to amylase among various starches, but it can be further digested under the high shear force. The mechanical, enzymatic hydrolysis and electrochemical properties of starch ghost make it widely used as emulsifier, stabilizer, thickener and starch-based films or gels in food and non-food processing industries.

Burgeoning Polymer Nano Blends for Improved Controlled Drug Release: A Review

With continual rapid developments in the biomedical field and understanding of the important mechanisms and pharmacokinetics of biological molecules, controlled drug delivery systems (CDDSs) have been at the forefront over conventional drug delivery systems. Over the past several years, scientists have placed boundless energy and time into exploiting a wide variety of excipients, particularly diverse polymers, both natural and synthetic. More recently, the development of nano polymer blends has achieved noteworthy attention due to their amazing properties, such as biocompatibility, biodegradability and more importantly, their pivotal role in controlled and sustained drug release in vitro and in vivo. These compounds come with a number of effective benefits for improving problems of targeted or controlled drug and gene delivery systems; thus, they have been extensively used in medical and pharmaceutical applications. Additionally, they are quite attractive for wound dressings, textiles, tissue engineering, and biomedical prostheses. In this sense, some important and workable natural polymers (namely, chitosan (CS), starch and cellulose) and some applicable synthetic ones (such as poly-lactic-co-glycolic acid (PLGA), poly(lactic acid) (PLA) and poly-glycolic acid (PGA)) have played an indispensable role over the last two decades for their therapeutic effects owing to their appealing and renewable biological properties. According to our data, this is the first review article highlighting CDDSs composed of diverse natural and synthetic nano biopolymers, blended for biological purposes, mostly over the past five years; other reviews have just briefly mentioned the use of such blended polymers. We, additionally, try to make comparisons between various nano blending systems in terms of improved sustained and controlled drug release behavior.

Modulating porosity and mechanical properties of pectin hydrogels by starch addition

The use of blends to produce hydrogels allows modulating their characteristics as mechanical properties and microstructure. This work aimed to study the properties of pectin and starch hydrogel blends. Pectin gel was homogeneous and porous, while pectin/starch blends containing 50% or more pectin exhibited denser and closer network, indicating that starch reduced the porosity of pectin network. Such characteristic was associated with higher gel hardness, cohesiveness, firmness, and water holding capacity. The influence of total biopolymer concentration and type of process (extrusion and atomization) on particle formation were also evaluated indicating that among the tested formulations, pectin 1% and starch 1% blend was the only sample able to form particles under extrusion and atomization. The addition of 5% (w/v) microparticles to the grape nectar presented no influence on rheological parameters, maintaining the pseudoplastic behavior. Both the starch addition and the amount of polymers used impacted the micro and macrostructure of pectin gels.

Natural biodegradable polymers based nano-formulations for drug delivery: A review

Nanomedicines are now considered as the new-generation medication in the current era mainly because of their features related to nano size. The efficacy of many drugs in their micro/macro formulations is shown to have poor bioavailability and pharmacokinetics after oral administration. To overcome this predicament, use of natural/synthetic biodegradable polymeric nanoparticles (NPs) have gained prominence in the field of nanomedicine for targeted drug delivery to improve biocompatibility, bioavailability, safety, enhanced permeability, better retention time and lower toxicity. For drug delivery, it is essential to have biodegradable nanoparticle formulations for safe and efficient transport and release of drug at the intended site. Moreover, depending on the target organ, a suitable biodegradable polymer can be selected as the drug-carrier for target specific as well as for sustained drug delivery. The aim of this review is to present the current status and scope of natural biodegradable polymers as well as some emerging polymers with special characteristics as suitable carriers for drug delivery applications. The most widely preferred preparation methods are discussed along with their characterization using different analytical techniques. Further, the review highlights significant features of methods developed using natural polymers for drug entrapment and release studies.

Studies on effect of co-processing on palmyrah and maize starch mixtures using DOE approach

Starch mixture is an important approach in designing drug delivery system with modulated properties. The aim of the present work is to study the effect of pregelatinization on starch mixture by varying the concentration of palmyrah and maize starch. All the starch mixtures were statistically designed using 3² full factorial design. Further, the mixtures were characterized for physicochemical and drug release properties. The amylose content, water holding capacity (WHC), swelling and solubility power tend to increase with increase in pregelatinization time. The X-ray diffractogram (XRD) confirmed the reduction in crystallinity of starch mixture with increase in pregelatinization time. The FT-IR study confirmed the gelatinization characteristics of the mixture. All the pregelatinized starch mixture exhibited shear-thinning behavior. Micromeritic property of various starch mixture showed the good flow properties. Formulation with this novel excipient system, using paracetamol as model drug indicated its utility for immediate release dosage form.

Manufacture and Characterization of Mucoadhesive Buccal Films Based on Pectin and Gellan Gum Containing Triamcinolone Acetonide

The treatment of canker sores can be quite compromised by the short period of the drug in the place of action. In this context, there is a need to develop drug dosage forms that allow more contact with the oral mucosa providing prolonged drug release. Therefore, the aim of this work was to obtain and characterize buccal films based on pectin and gellan gum in order to evaluate the potential use of these natural polymers in the production of pharmaceutical dosage forms for controlled release of TA in the oral mucosa. Using a 23 full factorial design, eight formulations were prepared by solvent casting method. The raw materials and films were characterized using techniques such as FTIR, DSC, and TG. In addition, thickness, mechanical properties, mucoadhesive strength, swelling, drug content, and dissolution profile of the films were evaluated. The results of FTIR, DSC, and TG showed that new chemical species are not formed in the production of films, and that these dosage forms have an adequate thermal behavior. All formulation showed a high degree of swelling, good mechanical resistance and elasticity, and a good mucoadhesive strength as well as able to act as a controlled release system.

Pectin and Pectin-Based Composite Materials: Beyond Food Texture

Pectins are plant cell wall natural heteropolysaccharides composed mainly of α-1-4 d-galacturonic acid units, which may or may not be methyl esterified, possesses neutral sugars branching that harbor functional moieties. Physicochemical features as pH, temperature, ions concentration, and cosolute presence, affect directly the extraction yield and gelling capacity of pectins. The chemical and structural features of this polysaccharide enables its interaction with a wide range of molecules, a property that scientists profit from to form new composite matrices for target/controlled delivery of therapeutic molecules, genes or cells. Considered a prebiotic dietary fiber, pectins meetmany regulations easily, regarding health applications within the pharmaceutical industry as a raw material and as an agent for the prevention of cancer. Thus, this review lists many emergent pectin-based composite materials which will probably palliate the impact of obesity, diabetes and heart disease, aid to forestall actual epidemics, expand the ken of food additives and food products design.

Comparison of the Analgesic Effect of Diclofenac Sodium-Eudragit(®) RS100 Solid Dispersion and Nanoparticles Using Formalin Test in the Rats

PURPOSE

In this study the intensity and duration of analgesic effect of diclofenac Na - Eudragit(®) RS100 solid dispersion and nanoparticles were evaluated by using formalin test in the rats.

METHODS

The animals received different formulations of diclofenac Na and subsequently 50 μl of formalin solution (2.5%) was injected subcutaneously in the right paws after 1 h, 2 h and 3 h. The paw licking behavior was then evaluated in two phases. A dose of 20 mg/kg of pure diclofenac Na powder was determined as effective dose.

RESULTS

In the first phase, in term of reduced paw licking time, no significant differences were found in any of the groups compared to the control group. However, in the second phase, the animals which received pure drug powder and the physical mixture of diclofenac Na with Eudragit(®) RS100 showed significant differences at the first and second hours. In the animals received the nanoparticles and solid dispersion, significant differences were observed in the third hour compared to the control group.

CONCLUSION

The analgesic effect of diclofenac Na could be improved by formulating its nanoparticles and solid dispersion with Eudragit(®) RS100. However, the nanoparticles revealed significantly higher analgesic effect than solid dispersion.