Hydrophobic grafted and cross-linked starch nanoparticles for drug delivery

Amphiphilic hydroxyethyl starch-based nanoparticles carrying linoleic acid modified berberine inhibit the expression of krasv12 oncogene in zebrafish

Cancer is one of the most lethal diseases all over the world. Despite that many drugs have been developed for cancer therapy, they still suffer from various limitations including poor treating efficacy, toxicity to normal human cells, and the emergence of multidrug resistance. In this study, the amphiphilic LHES polymers were prepared using hydroxyethyl starch (HES) and linoleic acid as starting materials. The content and substitution degree of linoleic acid groups in LHES polymers were analyzed. The LHES polymers were used for fabricating LHES-B nanoparticles carrying a linoleic acid modified berberine derivative (L-BBR). The LHES-B nanoparticles showed high drug loading efficiency (29%) and could quickly release L-BBR under acidic pH condition (pH = 4.5). Biological investigations revealed that LHES-B nanoparticles significantly inhibited the proliferation of HepG2 cells and exhibited higher cytotoxicity than L-BBR. In a transgenic Tg(fabp10:rtTA2s-M2; TRE2:EGFP-krasv12) zebrafish model, LHES-B nanoparticles obviously inhibited the expression of krasv12 oncogene. These results indicated that LHES carriers could improve the anticancer activity of L-BBR, and the synthesized LHES-B nanoparticles showed great potential as anticancer drug.

The Advancement and Obstacles in Improving the Stability of Nanocarriers for Precision Drug Delivery in the Field of Nanomedicine

Nanocarriers have emerged as a promising class of nanoscale materials in the fields of drug delivery and biomedical applications. Their unique properties, such as high surface area- tovolume ratios and enhanced permeability and retention effects, enable targeted delivery of therapeutic agents to specific tissues or cells. However, the inherent instability of nanocarriers poses significant challenges to their successful application. This review highlights the importance of nanocarrier stability in biomedical applications and its impact on biocompatibility, targeted drug delivery, long shelf life, drug delivery performance, therapeutic efficacy, reduced side effects, prolonged circulation time, and targeted delivery. Enhancing nanocarrier stability requires careful design, engineering, and optimization of physical and chemical parameters. Various strategies and cutting-edge techniques employed to improve nanocarrier stability are explored, with a focus on their applications in drug delivery. By understanding the advances and challenges in nanocarrier stability, this review aims to contribute to the development and implementation of nanocarrier- based therapies in clinical settings, advancing the field of nanomedicine.

Enhancing Oil Recovery by Polymeric Flooding with Purple Yam and Cassava Nanoparticles

Significant amounts of oil remain in the reservoir after primary and secondary operations, and to recover the remaining oil, enhanced oil recovery (EOR) can be applied as one of the feasible options remaining nowadays. In this study, new nano-polymeric materials have been prepared from purple yam and cassava starches. The yield of purple yam nanoparticles (PYNPs) was 85%, and that of cassava nanoparticles (CSNPs) was 90.53%. Synthesized materials were characterized through particle size distribution (PSA), Zeta potential distribution, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and transmission electron microscopy (TEM). The performance of PYNPs in recovering oil was better than CSNPs, as found from the recovery experiments. Zeta potential distribution results confirmed the stability of PYNPs over CSNPs (-36.3 mV for PYNPs and -10.7 mV for CSNPs). The optimum concentration for these nanoparticles has been found from interfacial tension measurements and rheological properties, and it was 0.60 wt.% for PYNPs and 0.80 wt.% for CSNPs. A more incremental recovery (33.46%) was achieved for the polymer that contained PYNPs in comparison to the other nano-polymer (31.3%). This paves the way for a new technology for polymer flooding that may replace the conventional method, which depends on partially hydrolyzed polyacrylamide (HPAM).

Carboxymethyl cellulose/starch/reduced graphene oxide composite as a pH-sensitive nanocarrier for curcumin drug delivery

Nanocomposites are promising drug carriers to treat terminal cancers with few adverse effects. Herein, nanocomposite hydrogels composed of carboxymethyl cellulose (CMC)/starch/reduced graphene oxide (RGO) were synthesized via a green chemistry approach and then encapsulated in double nanoemulsions to act as pH-responsive delivery systems for curcumin, a potential antitumor drug. A water/oil/water nanoemulsion containing bitter almond oil served as a membrane surrounding the nanocarrier to control drug release. DLS and zeta potential measurements were used to estimate the size and confirm the stability of curcumin-loaded nanocarriers. The intermolecular interactions, crystalline structure and morphology of the nanocarriers were analyzed through FTIR spectroscopy, XRD and FESEM, respectively. The drug loading and entrapment efficiencies were significantly improved compared to previously reported curcumin delivery systems. In vitro release experiments demonstrated the pH-responsiveness of the nanocarriers and the faster curcumin release at a lower pH. The MTT assay revealed the increased toxicity of the nanocomposites against MCF-7 cancer cells compared to CMC, CMC/RGO or free curcumin. Apoptosis was detected in MCF-7 cells via flow cytometry tests. The results obtained herein support that the developed nanocarriers are stable, uniform and effective delivery systems for a sustained and pH-sensitive curcumin release.

Encapsulation in Amylose Inclusion Complex Enhances the Stability and Release of Vitamin D

Vitamin D plays a significant role in the physiological functions of the human body. However, the application of vitamin D in functional foods is limited due to its sensitivity to light and oxygen. Therefore, in this study, we developed an effective method to protect vitamin D by encapsulating it in amylose. In detail, vitamin D was encapsulated by amylose inclusion complex, followed by structural characterization and evaluation of its stability and release properties. The results of X-ray diffraction, differential scanning calorimetry, and Fourier transform infrared spectroscopy showed that vitamin D was successfully encapsulated in the amylose inclusion complex, and the loading capacity was 1.96% ± 0.02%. The photostability and thermal stability of vitamin D after encapsulation was increased by 59% and 28%, respectively. In addition, in vitro simulated digestion showed that vitamin D was protected through the simulated gastric environment and can be released gradually in the simulated intestinal fluid, implying its improved bioaccessibility. Our findings provide a practical strategy for the development of functional foods based on vitamin D.

Synthesis, characterization, and in vivo safety evaluation of propylated Dioscorea abyssinica starch

The use of starch, a natural polymeric material, and derivatives thereof is based on its adhesive, thickening, gelling, swelling, and film-forming properties, as well as its ready availability. The objective of this research work is to develop an effective propylated Dioscorea abyssinica starch (PDAS) as a hydrophobic excipient for pharmaceutical applications with a reasonable price. This paper reports on the synthesis, characterization, and in vivo safety evaluation of PDAS. Native Dioscorea abyssinica starch (NDAS) was modified to its propylated form with propionic anhydride and characterized. Crystallinity, morphological structure, thermal behavior, solubility, and safety of PDAS were evaluated using x-ray diffraction, SEM, thermogravimetric, gravimetric, and toxicity studies, respectively. Propionyl content and degree of substitution (DS) of starch increased significantly (p < 0.05) with an increase in reaction time and temperature. Propionyl content and DS of starch increased significantly (p < 0.05) with a decrease in the ratio of starch to pyridine and starch to propionic anhydride in the reaction medium. FTIR spectra of PDAS indicated that hydroxyl groups participated in the propylation reaction. X-ray diffraction results showed that the chemical modification destroyed the crystalline structure of the NDAS. SEM of NDAS showed a rounded shape which became irregular after propylation. Thermogravimetric curves revealed that all the PDAS samples decomposed at higher temperatures than their native counterparts. At higher DS, swelling power and solubility in an aqueous environment significantly (p < 0.05) decreased below that of the native starch. PDAS with high DS, were soluble in organic solvents at room temperature. But PDAS with lower DS didn't dissolve in all types of organic solvents used. PDAS (DS = 2.842) in distilled water did not produce adverse effects in rats. Based on the results obtained, it can be concluded that PDAS can be considered as a generally safe excipient and fulfills the physicochemical properties of a hydrophobic excipient.

Polysaccharide-based nanosystems: a review

Polysaccharide-based nanosystem is an umbrella term for many areas within research and technology dealing with polysaccharides that have at least one of their dimensions in the realm of a few hundreds of nanometers. Nanoparticles, nanocrystals, nanofibers, nanofilms, and nanonetworks can be fabricated from many different polysaccharide resources. Abundance in nature, cellulose, starch, chitosan, and pectin of different molecular structures are widely used to fabricate nanosystems for versatile industrial applications. This review presents the dissolution and modification of polysaccharides, which are influenced by their different molecular structures and applications. The dissolution ways include conventional organic solvents, ionic liquids, inorganic strong alkali and acids, enzymes, and hydrothermal treatment. Rheological properties of polysaccharide-based nano slurries are tailored for the purpose functions of the final products, e.g., imparting electrostatic functions of nanofibers to reduce viscosity by using lithium chloride and octenyl succinic acid to increase the hydrophobicity. Nowadays, synergistic effects of polysaccharide blends are increasingly highlighted. In particular, the reinforcing effect of nanoparticles, nanocrystals, nanowhiskers, and nanofibers to hydrogels, aerogels, and scaffolds, and the double network hydrogels of a rigid skeleton and a ductile substance have been developed for many emerging issues.

Chemical modification of waxy maize starch by esterification with saturated fatty acid chlorides: Synthesis, physicochemical and emulsifying properties

In the current study, the physicochemical and emulsifying properties of modified waxy maize starch obtained through a new environmentally friendly method of esterification were evaluated. The starch modification was carried out in NaOH solution with different levels of octanoyl, myristoyl, and stearoyl chlorides. Increasing the fatty acid chlorides concentration led to the degree of substitution increment, while reaction efficiency and yield decreased. Based on fourier transform infrared spectroscopy results, the presence of two new bands of carbonyl (1740-1750 cm^-1) and carboxyl (1570 cm^-1) groups in the ester bond confirmed the successful starch esterification process. The level of 0.1 mL fatty acid chlorides/g of starch demonstrated the highest emulsifying properties. Upon esterification, the crystalline structure of amylopectin was destroyed, indicating no gelatinization features. Therefore, using the fatty acid chlorides in an alkaline condition could be suggested as a feasible way to modify waxy maize starch toward hydrophobicity increment with desirable properties.

One-Step Synthesis of Cross-Linked Esterified Starch and Its Properties

Cross-linked esterified starch (CES) was prepared using a one-step method, where maize starch was selected as the raw material, sodium trimetaphosphate as the cross-linking agent, and acetic anhydride as the esterifying agent, respectively. A response surface experiment was systematically conducted for analyzing the correlation of the experimental variables (cross-linked temperature, pH, reaction time, sodium trimetaphosphate and acetic anhydride dosage) and properties of the product (peak and final viscosity). The Brabender viscosity, freeze-thaw stability, shearing resistance, and acid tolerance of the cross-linked acetylated dual modified starch were studied under different conditions of crosslinking degree and acetyl content. Meanwhile, the granular structure and morphology of the modified starch were analyzed. The results indicated that: after cross-linked acetylated dual modification, the starch had a distinct birefringence and granular structure, along with the creation of new carbonyl groups. The low degree of crosslinking and high acetyl contents were beneficial to the viscosity, which was significantly increased at both low and high temperatures. Moreover, the freeze-thaw stability of CES was elevated sharply after five cycles. In addition, CES displayed increased shear and acid tolerance compared to the original waxy maize, and their lowest differences between waxy maize and CES were only 0.62% and 0.59%, respectively. In summary, a novel method for starch modification was provided, and the synthesized CES was suggested to have exceptional performance for the food industry.

Magnetic graphene oxide-lignin nanobiocomposite: a novel, eco-friendly and stable nanostructure suitable for hyperthermia in cancer therapy

In this research, a novel magnetic nanobiocomposite was designed and synthesized in a mild condition, and its potential in an alternating magnetic field was evaluated for hyperthermia applications. For this purpose, in the first step, graphene oxide was functionalized with a natural lignin polymer using epichlorohydrin as the cross-linking agent. In the second step, the designed magnetic graphene oxide-lignin nanobiocomposite was fabricated by the in situ preparation of magnetic Fe3O4 nanoparticles in the presence of graphene oxide functionalized with lignin. The resultant magnetic nanobiocomposite possessed certain main properties, including stability and homogeneity in aqueous solutions, making it suitable for hyperthermia applications. The chemical and structural properties of the synthesized magnetic graphene oxide-lignin composite were characterized using FT-IR, EDX, FE-SEM, TEM, TG and VSM analyses. The saturation magnetization value of this magnetic nanocomposite was recorded as 17.2 emu g-1. Further, the maximum specific absorption rate was determined to be 121.22 W g-1. Given these results, this newly fabricated magnetic nanobiocomposite may achieve considerable performance under the alternating magnetic field in fluid hyperthermia therapy.

Development of a polymeric nanocomposite as a high performance adsorbent for Pb(II) removal from water medium: Equilibrium, kinetic and antimicrobial activity

In the present study, starch based ZnO nancomposite (CSt-ZnO) was synthesized for the efficient removal of Pb(II) ions from aqueous medium. The structure and morphology of CSt-ZnO nancomposite was characterized using SEM, FTIR, TGA, BET, XPS and zeta potential measurements. The effect of contact time, pH, temperature and initial concentration of Pb(II) on the adsorption was studied. The optimum parameters for maximum Pb(II) removal were time-120 min; pH-6; temperature-318 K and C_o-20 ppm. The maximum Langmuir adsorption capacity of CSt-ZnO nancomposite was 256.4 mg/g at 298 K. With increasing the temperature from 298 K to 318 K, the maximum adsorption quantity (q_m) was improved from 256.4 to 476 mg/g which showed the endothermic nature of Pb(II) adsorption on CSt-ZnO nanocomposite. The sorption isotherm and kinetics model fitting studies, confirmed that data fit well to Freundlich isotherm and pseudo-first-order kinetics models, respectively. Thermodynamic studies inferred a spontaneous and endothermic nature of adsorption. Moreover, the adsorption capacity was 68% even after four adsorption-desorption cycles which revealed the reusable performance of CSt-ZnO was well. The antimicrobial activity of CSt-ZnO nanocomposite was also examined against S. aureus and E. coli.

Review of the Most Important Methods of Improving the Processing Properties of Starch toward Non-Food Applications

Starch is the second most abundantly available natural polymer in the world, after cellulose. If we add its biodegradability and non-toxicity to the natural environment, it becomes a raw material very attractive for the food and non-food industries. However, in the latter case, mainly due to the high hydrophilicity of starch, it is necessary to carry out many more or less complex operations and processes. One of the fastest growing industries in the last decade is the processing of biodegradable materials for packaging purposes. This is mainly due to awareness of producers and consumers about the dangers of unlimited production and the use of non-degradable petroleum polymers. Therefore, in the present review, an attempt was made to show the possibilities and limitations of using starch as a packaging material. The most important physicochemical features of this biopolymer are discussed, and special attention is paid to more or less environmentally friendly methods of improving its processing properties.

The preparation of modified nano-starch and its application in food industry

Starch, which is a carbohydrate polymer with a semicrystalline granular structure, has been the subject of academic research for decades due to its renewable and biodegradable property as well as various applications in food, pharmaceutical and other industries. Nano-starch (NS) is a novel type of starch material with unique physiochemical properties due to its small size. However, the nano-size nature of NS determines its tendency to agglomeration as a natural process to approach a thermodynamically steady state, and the single hydroxyl functional group is also not favorable to its applications in hydrophobic environments. Thus, modified-NS with improved dispersion property, hydrophobicity, and stability is emerging as a new research direction. However, information about modified-NS is sporadic in literature, and a systematic review from its preparation, application, the problem and challenge as well as related health concerns is carried out to further the understanding of modified-NS. It is expected that the theoretical basis and new insight into the development of modified-NS will be improved.

Interior of Amylopectin and Nano-Sized Amylopectin Fragments Probed by Viscometry, Dynamic Light Scattering, and Pyrene Excimer Fluorescence

Nano-sized amylopectin fragments (NAFs), prepared by extrusion of waxy corn starch, were investigated by viscometry, dynamic light scattering (DLS), and pyrene excimer fluorescence (PEF). NAF57, with a hydrodynamic diameter of 57 nm, was treated with nitric acid to yield three degraded NAFs, which appeared to share the same interior and structural features as amylopectin based on their measured intrinsic viscosity and hydrodynamic diameter. This conclusion was further supported by comparing the efficiency of forming excimer between an excited and a ground-state pyrenyl label covalently attached to the NAFs (Py-NAFs) using their I_E/I_M ratio of the fluorescence intensity of the excimer (I_E) to that of the monomer (I_M). The overlapping trends obtained for all Py-NAFs and the pyrene-labeled amylopectin samples by plotting the I_E/I_M ratio as a function of pyrene content provided further evidence that the interior of NAFs and amylopectin shared the same structural features and contained a similar amount of free volume as predicted by the Solution-Cluster (Sol-CL) model. The presence of free volume was validated by adding linear poly(ethylene glycol) (PEG) chains that could not penetrate the interior of Py-NAFs, thus subjecting the Py-NAFs to increased osmotic pressure, which induced their compression and resulted in an increase in I_E/I_M.

Applications of Fourier transform infrared spectroscopy to pharmaceutical preparations

Introduction: Various pharmaceutical preparations are widely used for clinical treatment. Elucidation of the mechanisms of drug release and evaluation of drug efficacy in biological samples are important in drug design and drug quality control.Areas covered: This review classifies recent applications of Fourier transform infrared (FTIR) spectroscopy in the field of medicine to comprehend drug release and diffusion. Drug release is affected by many factors of preparations, such as drug delivery system and microstructure polymorphism. The applications of FTIR imaging and nano-FTIR technique in biological samples lay a foundation for studying drug mechanism in vivo.Expert opinion: FTIR spectroscopy meets the research needs on preparations to understand the processes and mechanisms underlying drug release. The combination of attenuated total reflectance-FTIR imaging and nano-FTIR accompanied by chemometrics is a potent tool to overcome the deficiency of conventional infrared detection. FTIR shows an enormous potential in drug characterization, drug quality control, and bio-sample detection.

Application of some nanoparticles in the field of veterinary medicine

Nanotechnology is a fast-growing technology that plays an important great impact on various fields of therapeutic applications. It is capable for solving several problems related to animal health and production. There are different nano-systems such as liposomes, metallic nanoparticles, polymeric micelles, polymeric nanospheres, functionalized fullerenes, carbon nanotubes, dendrimers, polymer-coated nanocrystals and nanoshells. In this review, we mentioned different methods for the preparation and characterization of nanoparticles. This review is concerned mainly on nanoparticle systems for antibiotic delivery which suffer from poor bioavailability and many side effects. Nanoparticles are characterized by many features include their minimal size, colossal surface zone to mass extent. The development of antimicrobials in nanoparticle systems is considered an excellent alternative delivery system for antimicrobials for the treatment of microbial diseases by increasing therapeutic effect and overcoming the side effects. In this paper, we reviewed some antimicrobial nanoparticle preparations and we focused on florfenicol and neomycin nanoparticle preparations as well as chitosan and silver nanoparticles preparations to prepare, characterize and compare their different pharmacological effects.

Facile synthesis of Ca2+-crosslinked sodium alginate/graphene oxide hybrids as electro- and pH-responsive drug carrier

The design of stimuli-responsive drug carrier for controlled drug release is of significant importance in pharmaceutics, medicine and biology. Here, sodium alginate (SA) was integrated with graphene oxide (GO) by using Ca²⁺ as the crosslinker. The resultant SA-Ca²⁺-GO composites were freeze-dried to produce SA-Ca²⁺-GO hybrids, which were then examined by Fourier transform infrared (FT-IR) spectrometry, field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). The SA-Ca²⁺-GO hybrids were used as the drug carrier of methotrexate (MTX), and electro- and pH-responsive release of MTX was successfully achieved due to the excellent conductive ability of GO and the pH-sensitive property of SA. Finally, Higuchi model was employed to investigate the release kinetics of MTX from the SA-Ca²⁺-GO hybrids, and the results indicate that the release of MTX is controlled by Fickian diffusion.

Surfactant Structure-Dependent Interactions with Modified Starch Nanoparticles Probed by Fluorescence Spectroscopy

The interactions between the surfactants sodium dodecyl sulfate (SDS) and sodium dioctyl sulfosuccinate (AOT) and starch nanoparticles (SNPs) hydrophobically modified with the hydrophobic dye pyrene (Py-SNPs) were investigated in water by steady-state and time-resolved fluorescence. The Py-SNPs formed interparticulate aggregates in water, which were disrupted by adding SDS to the Py-SNP aqueous dispersions. SDS was found to interact with Py-SNPs at SDS concentrations that were close to 2 orders of magnitude lower than its critical micelle concentration (CMC). These interactions led to the breakup of the Py-SNP aggregates, which was confirmed by conducting fluorescence resonance energy transfer experiments between naphthalene-labeled SNPs (Np-SNPs) and Py-SNPs. By the time the SDS concentration reached the CMC of SDS, the Py-SNPs were separated from each other and excimer was generated from isolated Py-SNPs in the aqueous dispersions. Whereas SDS interacted with the Py-SNPs at SDS concentrations lower than CMC, SDS did not seem to target the hydrophobic pyrene aggregates. Only above the CMC did SDS appear to interact with the pyrene aggregates, as evidenced from diffusive pyrene excimer formation between excited and ground-state pyrenes. Most surprisingly, no interaction was observed between sodium dioctyl sulfosuccinate (AOT) and Py-SNP at AOT concentrations where SDS interacted with the Py-SNPs. This observation led to the conclusion that SDS below its CMC interacted not with hydrophobic pyrene aggregates but rather through the formation of inclusion complexes, which led to the electrostatic stabilization of individual Py-SNPs and enabled the breakup of Py-SNP aggregates. The formation of inclusion complexes with linear surfactants like SDS might thus provide a new means of stabilizing hydrophobically modified starch nanoparticles in water, which bears the promise of finding future applications.

Design of minocycline-containing starch nanocapsules for topical delivery

Pharmaceutical research has been focussed on developing improved delivery systems while exploring new ways of using approved excipients. The present work investigated the potential of starch nanocapsules (StNC) as a topical delivery platform for hydrophilic antimicrobial drugs using minocycline hydrochloride (MH) as a model drug. Thus, a quality by design approach was used to assess the role of different factors that affect the main pharmaceutical properties of StNC prepared using an emulsification-solvent evaporation method. Full characterisation was performed in terms of particle size, encapsulation efficiency, morphology and physical stability at 5 ± 3 °C. Results show the surfactant and lipid contents play a major role in StNC particle size distribution. The MH loading only promoted minor changes upon StNC properties. Formulations were stable without variations on physicochemical properties. All tested formulations presented a zeta-potential of +33.6 ± 6.7 mV, indicating a good physical stability and evidencing that StNC are suitable nanocarriers for topical use.

Applications of Pyrene Fluorescence to the Characterization of Hydrophobically Modified Starch Nanoparticles

Several aspects of pyrene fluorescence were applied to gain an insight into the nature of the microdomains in hydrophobically modified starch nanoparticles (HM-SNPs), prepared by reacting SNPs with propionic and hexanoic anhydride to yield C3- and C6-SNPs, respectively. The fluorescence experiments took advantage of the inherent hydrophobicity of pyrene to bind onto the hydrophobic domains generated by the HM-SNPs, and its specific response to the polarity of its environment, to probe its accessibility to quenchers such as oxygen or nitromethane dissolved in water. The equilibrium constant K_B for the binding of pyrene onto HM-SNPs, the ratio ( I₁/ I₃)_o describing the relative hydrophobicity of the microenvironment experienced by pyrene, its lifetime (τ_SNP), and the rate constant of quenching of pyrene bound to the HM-SNPs by water-soluble nitromethane ( k_qSNP) were determined as a function of the degree of substitution and weight fraction (wt %) of the hydrophobic modifier. The C3- and C6-SNPs yielded similar parameters at low levels of hydrophobic modification, indicating higher hydrophobicity of the modified SNPs with increasing modification level. However, SNPs modified with more than 5 wt % of hexanoyl pendants all displayed enhanced hydrophobicity for the C6-SNPs relative to the C3-SNPs. This substantial enhancement is attributed to the formation of larger hydrophobic microdomains by the hexanoyl pendants of the C6-SNPs above the 5 wt % C6-modification threshold, which did not occur with the C3-SNPs. Finally, the size of the SNPs did not appear to influence their relative hydrophobicity. These experiments demonstrate how the fluorescence of pyrene can be harnessed to provide information about the relative hydrophobicity of HM-SNPs.

Development of resistant corn starch for use as an oral colon-specific nanoparticulate drug carrier

Starch is constituted of amylose and amylopectin. Debranching of amylopectin converts it into amylose thereby producing resistant starch which is known to be less digestible by the amylase. This study designed resistant starch using acid hydrolysis and heat-moisture treatment methods with native corn starch as the starting material. Both native and processed starches were subjected to Fourier transform infrared spectroscopy, X-ray diffractometry, differential scanning calorimetry and molecular weight analysis. They were nanospray-dried into nanoparticles with 5-fluorouracil as the drug of interest for colon cancer treatment. These nanoparticles were subjected to size, zeta potential, morphology, drug content and in vitro drug release analysis. Heat-moisture treatment of native corn starch enabled the formation of resistant starch through amylopectin debranching and molecular weight reduction thereby enhancing hydrogen bonding between the starch molecules at the amorphous phase and gelatinization capacity. The nanoparticles prepared from resistant starch demonstrated similar drug release as those of native starch in spite of the resistant starch had a lower molecular weight. The resistant starch is envisaged to be resistant to the digestive action of amylase in intestinal tract without the formed nanoparticles exhibiting excessively fast drug release in comparison to native starch. With reduced branching, it represents an ideal precursor for targeting ligand conjugation in design of oral colon-specific nanoparticulate drug carrier.

Development of Novel Lignin-Based Targeted Polymeric Nanoparticle Platform for Efficient Delivery of Anticancer Drugs

The clinical applications of natural anticancer drugs are being restricted by poor water solubility, fast clearance in the circulation, lack of targeting to tumor cells, and poor tissue penetration. To address these problems, in this study, we developed a novel lignin-based targeted polymeric nanoparticles (NPs) platform, folic acid-polyethylene glycol-alkaline lignin conjugates (FA-PEG-AL), via self-assembly for delivery of anticancer drug (hydroxyl camptothecin, HCPT). These lignin-based nanoparticles had moderate particle size (∼150 nm) with a narrow size distribution (PDI < 0.1), exhibited excellent biocompatibility, high drug loading efficiency (∼24.2 wt % of HCPT), prolonged blood circulation time (∼7-fold of free HCPT), and enhanced cellular uptake (∼5-fold of free HCPT). Besides, the drug biodistribution study confirmed preferred accumulation of FA-PEG-AL/HCPT NPs in tumor tissue. Subsequent tumor xenograft test revealed superior tumor suppression efficacy and reduced side effects of FA-PEG-AL/HCPT NPs compared with free HCPT. Therefore, the prepared lignin-based FA-PEG-AL/HCPT NPs would be a promising candidate for anticancer drugs delivery.

Fabrication of asymmetric nanostarch reinforced Chitosan/PVP membrane and its evaluation as an antibacterial patch for in vivo wound healing application

Starch is an abundant, relatively inexpensive and ecofriendly materials which can be easily convert into nanoparticle and also as filler for the preparation of bionanocomposite for wound dressing application. Symmetric and asymmetric Chitosan(C)/PVP(P) films containing porous structure supported with nanostarch (NS) were prepared by salt leaching method for wound dressing application. Symmetric Chitosan/PVP/Nanostarch (CPNS) film with 1% and 3% wt nanostarch was prepared without coating of stearic acid whereas asymmetric Chitosan/PVP/Nanostarch-Stearic acid (CPNS-S) film was prepared by coating of stearic acid. The stearic acid coated surface possesses hydrophobic water repellent, microporous, bacterial anti adhesion property and the stearic acid uncoated hydrophilic surface shows superior antibacterial and noncytotoxicity property with highly porous character. All the symmetric and asymmetric films exhibit almost same mechanical, barrier, swelling and hemolytic property reveals that the stearic acid does not affect the physical and hemolytic property whereas the concentration of nanostarch greatly influence the above property. The reinforcement of nanostarch with chitosan and PVP was proved by TEM and SEM analysis. The CPNS1%-S film shows excellent S. aureus anti adhesion property. Furthermore, the in vivo excision-type wound healing proved that the CPNS1%-S film enhanced the healing effect and increased re-epithelialization and collagen formation.

Ultrasonic-assisted fabrication of starch/MWCNT-glucose nanocomposites for drug delivery

The principal focus of this investigation is to prepare starch nanocomposite (NC) films containing multi-walled carbon nanotube (MWCNT) and apply these NCs for drug delivery. Firstly, to raise the hydrophilicity of carboxyl functionalized MWCNT, the surface of them was modified with d-glucose (Gl) as a low cost and environmentally friendly biomolecule. Different percentages of MWCNT-Gl (0.5, 1 and 2wt%) were embedded in starch matrix through sonochemical method as an economical, fast, eco-friendly, and effective method. The properties of starch/MWCNT-Gl NCs were characterized using Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, field emission scanning electron microscopy and transmission electron microscopy (TEM). Afterwards, pure starch and starch/MWCNT-Gl NCs were reacted with oleic acid to obtain amphiphilic (Amph) esters. Except Amph obtained from pure starch, other Amph esters could convert to drug-loaded nanoparticles which were characterized by dynamic light scattering and TEM. The sizes of nanoparticles depended on the value of MWCNT-Gl. The thinnest particles obtained from starch/MWCNT-Gl NCs containing the highest value of MWCNT-Gl (2wt%), and this system was chosen for measurement of entrapment efficiency, loading capacity and in vitro release study for zolpidem as a hydrophobic drug model.

New technique in starch nanoparticles synthesis

Starch nanoparticles (StNPs) were previously prepared using severe mechanical, physical and/or chemical conditions that takes too long time to produce a little yield of uncontrolled large size of StNP. The current work presents a new technique for the synthesis of StNPs based on the combination between sodium hydroxide and glycerol in aqueous medium during the synthesis process while the precipitation of the StNPs is performed under homogenization at ambient conditions. The new technique is based on three assumptions: 1) the dual impact of sodium hydroxide and glycerol on the swelling and gelatinization of starch as a pre-stage of the synthesis of (StNPs1), 2) the dual impact of glycerol and cooking of starch on the swelling and gelatinization of starch as a pre-stage of the formation of (StNPs2), and 3) the precipitation under homogenization at ambient conditions and its effect on breaking the H- bonds of the starch molecule in both StNPs1 and StNPs2. The importance of this technique arises from the ease of the process, the eco-friendly chemicals and the combination between the mechanical and chemical processes. NS (native starch), StNPs1 and StNPs2 were characterized using FTIR, XRD, TGA and TEM. TEM of StNPs1 showed a well-defined round particles uniformly distributed with size of about 62.5nm. StNPs2 showed a non-specific shape starch particles.

Nanotechnology Approaches for Increasing Nutrient Bioavailability

Health-promoting ingredients such as phenolic compounds, vitamins, and minerals are being increasingly introduced into foods and beverages to produce "functional foods" specifically designed to improve human health, well-being, and performance. However, it is often challenging to incorporate these nutraceuticals into foods because they have poor solubility characteristics, impart undesirable flavor profiles, are chemically unstable, or have low bioavailability. This problem can often be overcome by encapsulating the bioactive components in nanoparticle-based delivery systems. The bioavailability of encapsulated bioactive agents often increases when the size of the particles containing them decreases, due to their faster digestion, ability to penetrate the mucus layer, or direct uptake by cells. Nanoparticles can be formulated to survive passage through specific regions of the gastrointestinal tract and then release their payload at a specified point, thus maximizing their potential health benefits. Nutraceutical-loaded nanoparticles can be fabricated through lipid formulations, natural nanocarriers, specialized equipment, biopolymer nanoparticles, and miscellaneous techniques. Classification into these five groups is based on the main mechanism or ingredient used to fabricate the nanoparticles. This chapter focuses on the utilization of food-grade nanoparticles for improving the performance of nutraceuticals in functional foods and beverages.