Tripolyphosphate Research Articles

Fabrication of crosslinked starch microspheres via water-in-water Pickering emulsion and their application in controlled release of Vitamin C

Green technology for the fabrication of bio-degradable microspheres is exciting and needed. In this study, a new water-in-water Pickering emulsion green technology is proposed for the fabrication of the crosslinked starch microspheres with sodium tripolyphosphate as the crosslinker, polyethylene glycol aqueous solution as the continuous phase (PEG phase) and starch aqueous solution as the dispersed phase (starch phase). The factors that affect the morphology and particle sizes of cross-linked starch microspheres are investigated by laser scanning confocal microscope (LCM) and laser particle size analyzer. The results reveal that the particle sizes of crosslinked starch microspheres are increasing with increased starch concentration. The particle sizes of crosslinked starch microspheres show a first increase and then decrease trend with the increase of the concentration of PEG 20,000 in the PEG phase. The hydrophobic nano silica is used as an emulsifier to form water-in-water Pickering emulsion and shows an obvious effect on the morphology of starch microspheres. When the starch concentration is 20.00 wt%, PEG 20000 concentration is 32.56 wt%, the ratio of starch to PEG phase is 0.20 and the amount of silica is 5.00 wt% of starch, starch microspheres with regular shapes are obtained with the size of about 32.30 ± 0.22 µm. The fabricated cross-linked starch microspheres are non-crystalline and show good water and oil absorption performances. The application of fabricated crosslinked starch microspheres in the adsorption and release of Vitamin C is conducted. The maximum adsorption capacity of crosslinked starch microspheres for Vitamin C reaches 309.9 mg/g. Starch microspheres show a controlled release of Vitamin C in water. This study indicated that crosslinked starch microspheres can be fabricated through a green water-in-water Pickering emulsion technology and may find potential applications in degradable controlled-release microspheres.

Calendula Oil Associated Dexibuprofen Nanoformulation Transdermal Patches: Formulation and Characterization

Objectives: To prepare and characterize the nanoparticle-based topical formulations of dexibuprofen in combination with calendula oil to enhance the topical anti-inflammatory effect. Methods: Chitosan and tri poly phosphate (TPP) were used to prepare nanoparticles developed utilizing the ionotropic gelation technique and analyzed by scanning electron microscope (SEM) and the ZS. Solvent casting was used to prepare the transdermal medication delivery system for the chitosan nanoparticle formulation. Results: Results revealed that nanoparticles were between the sizes of 267.3 nm. This particle size may enhance the drug’s solubility and penetration through the skin. These patches containing chitosan nanoparticles were produced utilizing polymer combinations - HPMC, chitosan, and PEG400 with tween80 as plasticizers. Accompanying the rise in hydrophilic polymer content came an increase in the rate of medication release via the patch. Conclusion: Transdermal patch - F3 released the drug reasonably well.

Evaluating the antibacterial effect of meropenem-loaded chitosan/sodium tripolyphosphate (TPP) nanoparticles on Acinetobacter baumannii isolated from hospitalized patients

BackgroundAcinetobacter baumannii is a health threat due to its antibiotic resistance. Herein, antibiotic susceptibility and its association with the Toxin-antitoxin (TA) system genes in A. baumannii clinical isolates from Iran were investigated. Next, we prepared meropenem-loaded chitosan nanoparticles (MP-CS) and investigated their antibacterial effects against meropenem-susceptible bacterial isolates.MethodsOut of 240 clinical specimens, 60 A. baumannii isolates were assessed. Antibiotic resistance of the isolates against conventional antibiotics was determined alongside investigating the presence of three TA system genes (mazEF, relBE, and higBA). Chitosan nanoparticles were characterized in terms of size, zeta potential, encapsulation efficiency, and meropenem release activity. Their antibacterial effects were assessed using the well diffusion method, minimum inhibitory concentration (MIC), and colony-forming unit (CFU) counting. Their cytotoxic effects and biocompatibility index were determined via the MTT, LDH, and ROS formation assays.ResultsAmpicillin, ceftazidime, and colistin were the least effective, and amikacin and tobramycin were the most effective antibiotics. Out of the 60 isolates, 10 (16.7%), 5 (8.3%), and 45 (75%) were multidrug-resistant (MDR), extensively drug-resistant (XDR), and pandrug-resistant (PDR), respectively. TA system genes had no significant effect on antibiotic resistance. MP-CS nanoparticles demonstrated an average size of 191.5 and zeta potential of 27.3 mV alongside a maximum encapsulation efficiency of 88.32% and release rate of 69.57%. MP-CS nanoparticles mediated similar antibacterial effects, as compared with free meropenem, against the A. baumannii isolates with significantly lower levels of meropenem. MP-CS nanoparticles remarkably prevented A549 and NCI-H292 cell infection by the A. baumannii isolates alongside demonstrating a favorable biocompatibility index.ConclusionAntibiotic-loaded nanoparticles should be further designed and investigated to increase their antibacterial effect against A. baumannii and assess their safety and applicability in vivo settings.

Design and synthesis of chitosan/alginate/zinc oxide nanocomposite hydrogel beads as carrier for metformin hydrochloride

In the current study, nanocomposite hydrogel beads were prepared from chitosan, alginate and zinc oxide nanoparticles using sodium tripolyphosphate as the crosslinking agent by ionotropic gelation method. The resulting nanocomposite hydrogel beads were characterized by FT-IR, XRD, TGA and UV methods and the beads were found to be an effective delivery system for the regulated release of the antidiabetic drug metformin. The swelling properties, drug loading and encapsulation efficiencies of the metformin loaded nanocomposite beads were evaluated and these parameters were found to be influenced by the concentrations of chitosan, alginate and ZnO nanoparticles. The rate of release of the drug from the nanocomposite beads was determined by UV spectroscopic method at λmax 233 nm. An increase in the concentration of ZnO enhances the swelling properties but lowers the release rate. Swelling indices of the prepared formulations were in the range 5–150. Maximum swelling index of 150 was observed for the formulation with 3 % chitosan, 2 % alginate and 15 % zinc oxide NPs. However, a maximum release rate of 83.23 % was observed for the formulation without ZnO and with 3 % chitosan, 2 % alginate. Controlled drug release was observed for the drug loaded chitosan/alginate/ZnO, hydrogel beads. The zinc oxide nanoparticles improved the in vitro α-glucosidase inhibitory activity of the formulations and the formulation with 5 % ZnO exhibited a maximum α-glucosidase inhibition rate of 62.92 %. The incorporation of ZnO nanoparticles enhanced the antioxidant properties of the formulations. The cell viability values of the samples were evaluated using L929 mouse fibroblast cells which confirmed the nontoxic nature of the samples. Dinitrosalicylic acid (DNS) studies proved that the prepared nanocomposites are biodegradable.

Accurately recognizing chromium species with multi-functionalized nano Au-based sensor array

High-resolution identification of chromium (Cr) species, especially various organic-Cr complexes, in a convenient and economically-feasible manner is the prerequisite for achieving the advanced treatment of chromium wastewater. To this end, a colorimetric nano-Au sensor array was developed by taking advantage of the UV-spectra shift of gold nanoparticles (Au NPs) upon interaction with Cr species; specifically, four molecular modifiers [i.e., iminodiacetic acid (IDA), tripolyphosphate (TPP), cetyltrimethylammonium bromide (CTAB), and 1,5-diphenylcarbazide (DPC)] were intentionally employed for assembling nano-Au array receptors, which showed respective responses toward different Cr species through the formation of coordination, hydrophobic interaction, electrostatic attraction, and redox reaction, respectively; the “fingerprint” differences of the unique optical properties were then integrated for semi-quantitatively recognizing Cr species by pattern recognition techniques. Eleven ubiquitous Cr species [i.e., Cr(III), Cr(VI), and various Cr(III)-organic complexes] served as the model samples, which could be sensitively identified, no matter in individual or mixture mode, by the developed nano-Au sensor array on the basis of the colorimetric responses resulted from diverse nano-Au-aggregation behaviors, with excellent anti-interference ability in the simulated or actual water scenario. Attractively, the nano-Au sensor array can achieve very sensitive detection limit of the quantitative analyses of Cr species in a prompt in-situ manner, which usually requires a two-step process of separation and detection for the conventional analytical methods. Such a convenient strategy of Cr species discrimination conduces to rationally designing specific protocols for the advanced treatment of chromium wastewater.

Mechanochemical Synthesis of Cross-Linked Chitosan and Its Application as Adsorbent for Removal of Per- and Polyfluoroalkyl Substances from Simulated Electroplating Wastewater.

Chitosan is a promising adsorbent for removing a wide range of pollutants from wastewater. However, its practical application is hindered by instability in acidic environments, which significantly impairs its adsorption capacity and limits its utilization in water purification. While cross-linking can enhance the acid stability of chitosan, current solvent-based methods are often costly and environmentally unfriendly. In this study, a solvent-free mechanochemical process was developed using high-energy ball milling to cross-link chitosan with various polyanionic linkers, including dextran sulfate (DS), poly[4-styrenesulfonic acid-co-maleic acid] (PSSM), and tripolyphosphate (TPP). The mechanochemically cross-linked (MCCL) chitosan products exhibited superior adsorption capacity and stability in acidic solutions compared to pristine chitosan. Chitosan cross-linked with DS (Cht-DS) showed the highest Reactive Red 2 (RR2) adsorption capacity, reaching 1559 mg·g-1 at pH 3, followed by Cht-PSSM (1352 mg·g-1) and Cht-TPP (1074 mg·g-1). The stability of MCCL chitosan was visually confirmed by the negligible mass loss of Cht-DS and Cht-PSSM tablets in pH 3 solution, unlike the complete dissolution of the pristine chitosan tablet. The MCCL significantly increased the microhardness of chitosan, with the order Cht-DS > Cht-PSSM > Cht-TPP, consistent with the RR2 adsorption capacity. When tested on simulated rinsing wastewater from chromium electroplating, Cht-DS effectively removed Cr(VI) (98.75% removal) and three per- and polyfluoroalkyl substances (87.40-95.87% removal), following pseudo-second-order adsorption kinetics. This study demonstrates the potential of the cost-effective and scalable MCCL approach to produce chitosan-based adsorbents with enhanced stability, mechanical strength, and adsorption performance for treating highly acidic industrial wastewater containing a mixture of toxic pollutants.

Fabrication and characterization of unique sustain modified chitosan nanoparticles for biomedical applications

Chitosan (CS) is a biopolymer that offers a wide range in biomedical applications due to its biocompatibility, biodegradability, low toxicity and antimicrobial activity. Syringaldehyde (1) is a naturally occurring organic compound characterized by its use in multiple fields such as pharmaceuticals, food, cosmetics, textiles and biological applications. Herein, development of chitosan derivative with physicochemical and anticancer properties via Schiff base formation from the reaction of chitosan with sustainable eco-friendly syringaldehyde yielded the (CS-1) derivative. Moreover, in the presence of polyethylene glycol diglycidyl ether (PEGDGE) or sodium tripolyphosphate (TPP) as crosslinkers gave chitosan derivatives (CS-2) and (CS-3NPs) respectively. The chemical structures of the new chitosan derivatives were confirmed using different tools. (CS-3NPs) nanoparticle showed improvement in crystallinity, and (CS-2) derivative revealed the highest thermal stability compared to virgin chitosan. The cytotoxicity activity of chitosan and its derivatives were evaluated against HeLa (human cervical carcinoma) and HEp-2 (Human Larynx carcinoma) cell lines. The highest cytotoxicity activity was exhibited by (CS-3NPs) compared to virgin chitosan against HeLa cell growth inhibition and apoptosis of 90.38 ± 1.46% and 30.3% respectively and IC50 of 108.01 ± 3.94 µg/ml. From the above results, it can be concluded that chitosan nanoparticle (CS-3NPs) has good therapeutic value as a potential antitumor agent against the HeLa cancer cell line.

Analysis of physical characteristics and mechanism of retarder to stratified cemented backfill

The stratified structural plane caused by stratified backfill will reduce the strength of backfill, and the introduction of retarder will make up for the defect. Three retarders, sodium tripoly-phosphate, citric acid and sucrose, were introduced. After determining the optimal dosage of retarder, they were added into the filling slurry with a ratio of lime to sand of 1:6 and a mass concentration of 75%. Based on the hydration reaction mechanism and damage mechanics theory of cement, the setting time test and uniaxial compressive strength test were carried out. With the help of scanning electron microscopy and X-ray diffraction, the influence mechanism of retarder on the physical characteristics of stratified cemented filling was investigated.The main research contents and achievements are as follows:. The results showed that the three retarding agents can delay the setting time of the cement filling slurry, and the retarding effect is sucrose > citric acid > sodium tripolyphosphate. The addition of retarder can improve the uniaxial compressive strength and integrity of stratified consolidated backfill, and the best filling interval time (FIT) is 12 h. Appropriate addition of retarder will increase the amount of cement hydration products, make the structure of hydration products more dense, reduce the formation of stratified structural plane, and help to improve the strength of stratified cemented backfill.

STPP and EDTMPS synergistically enhance the flotation separation of scheelite from fluorite and calcite

In this paper, the synergistic effects of sodium tripolyphosphate (STPP) and sodium ethylenediamine tetramethylenephosphonate (EDTMPS) for the flotation separation from fluorite and calcite were investigated. Flotation tests conducted at various scales demonstrated that the combined inhibitor of STPP and EDTMPS can significantly enhance the separation efficiency of scheelite from fluorite and calcite. For low-grade scheelite in Luanchuan, the combined inhibitor can improve the WO3 grade of scheelite roughing concentrate without compromising the recovery of scheelite roughing, thereby reducing the burden of the Petrov process. Based on the results from X-ray photoelectron spectroscopy and atomic force microscopy, coupled with other surface analysis, it’s evident that STPP and EDTMPS are more readily adsorbed onto the surfaces of fluorite and calcite due to the unique in electrostatic repulsion and steric resistance.The co-adsorption of STPP and EDTMPS covers a more extensive mineral surface area, enhancing the hydrophilicity of fluorite and calcite surfaces. This, in turn, heightens the resistance of the mineral surfaces to subsequent sodium oleate (NaOL) adsorption. As a result, the floatability difference among the three calcium-bearing minerals is expanded, optimizing the separation efficiency.

Nanosuspension Formula of Curcuma xanthorriza Rhizome Dry Extract: Impact of Tween 80-PEG 400 Ratio

Our previous research investigated nanosuspension using the ionic gelation method with a 2:1 ratio of chitosan to sodium tripolyphosphate (TPP) and 0.44% Curcuma xanthorriza rhizome extract. The results indicated an unstable nanosuspension with a particle size of 399.3 nm, a polydispersity index of 0.60, and an entrapment efficiency of 73.37%. This study aims to develop a nanosuspension using Tween 80-PEG 400 to improve the characteristics and dissolution at pH 6.8. Curcuma rhizome was macerated with 96% ethanol and dried using a spray dryer. The nanosuspension formulation was designed using a 22 factorial design with Tween 80 (0.1%-0.4%) and PEG 400 (0.1%-0.4%) as factors, and the formulation was analyzed using Minitab 18. The dissolution of the optimum formulation was tested. The best formulation, comprising 0.1% Tween 80 and 0.4% PEG 400, provided a spherical shape, a particle size of 111.26 nm, a polydispersity index of 0.27, a zeta potential of 30.77 mV, an entrapment efficiency of 84.30%, and a desirability value of 0.9058. The release of curcumin at pH 6.8 after 180 minutes was 37.85% ± 0.1375 with a DE180 of 83.60% ± 0.1457. The 22 factorial design proved effective for enhancing formulation attributes. Based on the result obtained, it can be concluded that the best formulation contains 0.1% Tween 80 and 0.4% PEG 400, with zero-order release kinetics and a diffusion mechanism.

Physicochemical properties of tablet dosage form based on pre-gelatinized- and phosphorylated-modified starches from white-water yam (Dioscorea alata L.)

Abstract Background White-water yam (Dioscorea alata L.) is one of the potential sources of starch; however, it is not yet available for commercial purposes. Besides, native white-water yam starch (WS) presents limited functionality due to poor flowability, mechanical properties and instability at high temperature and acidic conditions. Therefore, this study aims to modify the starch to improve its characteristics and make it useful as an excipient for the preparation of the tablets. Materials and methods The modification of WS was achieved by physical and chemical treatments, specifically pre-gelatinization and phosphorylation, respectively. Pre-gelatinization WS involves heating, meanwhile phosphorylation WS is obtained by treating WS with sodium tripolyphosphate. Results The results showed that the powder of the modified WS has good characteristics which improved the flowability of the powder mixture as a granule based on density, porosity, compressibility index and swelling power determination. The WS granules were found to display the oval or irregular (polygonal) shape with the amylose content 11.92±0.61% for unmodified WS, 10.41±0.90% for pre-gelatinized WS and 12.61±1.75% for phosphorylated WS. Furthermore, the granule was formulated as an excipient in tablet preparations, and the formulas were compressed after wet granulation. The mechanical properties of the tablets were assessed using uniformity of mass and size, hardness, friability and disintegration time. WS modification affects the hardness of tablets when used as a binder. Phosphorylated WS is recommended to be used as a binder in wet granulation formulations because it produces tablets with a longer disintegration time, which means better binding ability. However, the utilization of modified WS with both pre-gelatinization and phosphorylation leads to tablets with low brittleness compared to others with unmodified binder with the disintegration time still met the requirement of fast disintegrating tablet (<15 minutes). Conclusion All the physical properties studied indicated that the modified WS is a promising pharmaceutical excipient in tablets.

Physicochemical Analysis of Spent Hen Chicken Sausages with Jelly Mushroom (Auricularia auricula) Powder Inclusion as a Substitute for Sodium Tripolyphosphate

Abstract This study aims to evaluate the substitution effect of the Sodium Tripolyphosphate (STPP) with jelly mushroom (Auricularia auricula) powder (JMP)at various concentration on quality attributes of the spent hen chicken sausages. Using a completely randomized design (CRD), this experiment consisting of five treatments and three replications. The treatments including group with 0,3% STPP (P0; w/w), and inclusion of jelly mushroom at 1%, 2%, and 3%, labelled with T1, T2, T3; w/w, respectively. The data obtained were statistically analyzed using analysis of variance (ANOVA) and continued with Duncan’s multiple range test (DMRT) at 5% level. The results showed that the increase in (JMP)substitution up to 3% levels had a significant effect on the tenderness, WHC, and pH value. The addition of (JMP)had no significant effect on the cooking loss, ranging from 4,74 to 6,33%. Substitutions of STPP with JMP in spent hen sausages even at the 1% level generated a significant effect on collagen, fat, and moisture contents and decreased protein content. The addition of jelly mushroom powder up to 1% levels will reduce fat, collagen, and moisture contents. This study inferred that the JMP can be used as an alternative substitution for STPP at the level of 1%, while the use of JMP in spent hen sausages at more than 1% would negatively affect the quality attributes of spent hen chicken sausage.

Fabrication of 3D chitosan/polyvinyl alcohol/brushite nanofibrous scaffold for bone tissue engineering by electrospinning using a novel falling film collector

Despite its advantages, electrospinning has limited effectiveness in 3D scaffolding due to the high density of fibers it produces. In this research, a novel electrospinning collector was developed to overcome this constraint. An aqueous suspension containing chitosan/polyvinyl alcohol nanofibers was prepared employing a unique falling film collector. Suspension molding by freeze-drying resulted in a 3D nanofibrous scaffold (3D-NF). The mineralized scaffold was obtained by brushite deposition on 3D-NF using wet chemical mineralization by new sodium tripolyphosphate and calcium chloride dihydrate precursors. The 3D-NF was optimized and compared with the conventional electrospun 2D nanofibrous scaffold (2D-NF) and the 3D freeze-dried scaffold (3D-FD). Both minor fibrous and major freeze-dried pore shapes were present in 3D-NFs with sizes of 16.11–24.32 μm and 97.64–234.41 μm, respectively. The scaffolds' porosity increased by 53 % to 73 % compared to 2D-NFs. Besides thermal stability, mineralization improved the 3D-NF's ultimate strength and elastic modulus by 2.2 and 4.7 times, respectively. In vitro cell studies using rat bone marrow mesenchymal cells confirmed cell infiltration up to 290 μm and scaffold biocompatibility. The 3D-NFs given nanofibers and brushite inclusion exhibited considerable osteoinductivity. Therefore, falling film collectors can potentially be applied to prepare 3D-NFs from electrospinning without post-processing.

A rapid protocol for synthesis of chitosan nanoparticles with ideal physicochemical features

In this research, an innovative protocol is introduced to address crucial deficiencies in the formulation of chitosan nanoparticles (Cs NPs). While NPs show potential in drug delivery systems (DDSs), their application in the clinic is hindered by various drawbacks, such as toxicity, high material costs, and time-consuming and challenging preparation procedures. Within polymer-based NPs, Cs is a plentiful natural substance derived from the deacetylation of chitin, which can be sourced from the shells of shrimp or crab. Cs NPs can be formulated using the ionic gelation technique, which involves the use of a negatively charged agent, such as tripolyphosphate (TPP), as a crosslinking agent. Even though Cs is a cost-effective and biocompatible material, the formulation of Cs NPs with the correct size and surface electrical charge (zeta potential) presents a persistent challenge. In this study, various techniques were employed to analyze the prepared Cs NPs. The size and surface charge of the NPs were evaluated using dynamic light scattering (DLS). Morphological analysis was conducted using field emission-scanning electron microscopy (FE-SEM). The chemical composition and formation of Cs NPs were investigated using Fourier transform infrared (FTIR). The stability analysis was confirmed through X-ray diffraction (XRD) analysis. Lastly, the biocompatibility of the NPs was assessed through cell cytotoxicity evaluation using the MTT assay. Moreover, here, 11 formulations with different parameters such as reaction pH, Cs:TPP ratio, type of Cs/TPP, and ultrasonication procedure were prepared. Formulation 11 was chosen as the optimized formulation based on its high stability of more than three months, biocompatibility, nanosize of 75.6 ± 18.24 nm, and zeta potential of +26.7 mV. To conclude, the method described here is easy and reproducible and can be used for facile preparation of Cs NPs with desirable physicochemical characteristics and engineering ideal platforms for drug delivery purposes.

Effect of Sodium Tripolyphosphate on The Morphology and Thermal Properties of Anorthite-Based Ceramic Foam Filters for Aluminum Alloy Castings

Effect of Sodium Tripolyphosphate on The Morphology and Thermal Properties of Anorthite-Based Ceramic Foam Filters for Aluminum Alloy Castings

The Effect of Sodium Tripolyphosphate and Guar Gum on Physical Characteristics of Analog Rice from Gaplek Flour

Gaplek flour is a processed product of cassava preservation abundant during the harvest season in Lampung Province. The high carbohydrate content in cassava facilitates the processing of gaplek flour into carbohydraterich food source, such as analog rice. Therefore, this study aimed to investigate the effect of adding STPP and guar gum on the formulation of analog rice made from 70% gaplek flour and 30% corn flour. Analog rice was produced using the extrusion method with a twin-screw extruder. The results showed that the addition of STPP did not affect water absorption characteristics. The solubility of rice in deep water also decreased with increasing amounts of STPP and guar gum. Meanwhile, guar gum significantly increased water absorption and reduced the solubility of rice in water. The degree of gelatinization decreased with the addition of both materials. The addition of 0.3-0.5% STPP and 0.5-2% guar gum had no significant effect on hardness, stickiness, elasticity, and cohesiveness of analog rice prepared using a cooker.

Cryoprotective Agents to Improve the Quality of Tambaqui Surimi (Colossoma macropomum)

One major method in fish processing to maximize utilization is through surimi preparation, extensively used in various products. To ensure desired organoleptic qualities, cryoprotective agents are crucial. This study aimed to evaluate the production potential of Amazon fish surimi prepared with different blends of cryoprotectants: CF (no cryoprotectant), S1 (2% sodium chloride, 1% sucrose), S2 (8% sorbitol, 0.5% sodium tripolyphosphate), and S3 (8% sucrose, 8% sorbitol, 0.5% sodium tripolyphosphate). Proximal composition and techno-functional properties were assessed. Moisture content (<79%) indicated excellent quality across all treatments. S2 had high protein (17.91%) and low lipid content, second only to S3. Increasing cryoprotectant concentration led to higher carbohydrate content and energy value. Color differences were insignificant except for luminosity (L*) influenced by sucrose in S1. Cryoprotectant treatments showed no significant texture or water retention differences, displaying a bending profile well-suited for the product. Univariate statistics and Principal Component Analysis concluded S2 blend as most suitable for tambaqui surimi (Colossoma macropomum) production regarding final nutritional and techno-functional gel characteristics.

Preparation of a novel DNA-imprinted sensor based on chitosan and its highly sensitive detection of Pb2+

Lead ion is very harmful to the environment, so it is very important to study its detection methods. In this study, a novel electrochemical sensor was constructed by modifying deoxyribonucleic acid (DNA) on the electrode, which can be used for the detection of Pb2+ in the environment. Part of the mixed solution of chitosan (CS) and Pb2+ template ions was dropped onto the surface of a glassy carbon electrode. CS-Pb2+ film was cross-linked through sodium tripolyphosphate. And a novel DNA-imprinted sensor was prepared by electrodepositing CS-Pb2+ thin film with gold nanoparticles (AuNPs), removing Pb2+ templates, and immobilizing specific double-stranded DNA. The electroactive area, surface morphology, sensitivity, and electrochemical reaction mechanism of the DNA-imprinted sensor were analyzed. The elementary reaction steps were studied through electrochemical reaction kinetics analysis. The experimental results indicate that the DNA-imprinted electrochemical biosensor can quantitatively detect Pb2+ in the range of 10–100 μM (R2 = 0.9935), and its detection limit is 6.5074 μM (3σ/slope). The sensitivity of the electrochemical biosensor is 1.55233 × 10−6 A/μM, and its active areas is 6.233 cm2. The desorption mechanism and adsorption mechanism have been explored through dynamic parameter analysis. The novel DNA imprinted electrochemical biosensor developed in this paper provides a robust method for detecting lead ions in solution. Additionally, it establishes a solid groundwork for detecting other metal ions.

Understanding the mechanism for sodium tripolyphosphate in improving the physicochemical properties of low-moisture extrusion textured protein from rapeseed protein and soybean protein blends

Our previous experiments found that rapeseed protein (RP) has applicability in low-moisture textured proteins. The amount of RP added is limited to <20 %, but the addition of 20 % RP still brings some negative effects. Therefore, in order to improve the quality of 20%RP textured protein, this experiment added different proportions of sodium tripolyphosphate (STPP) to improve the quality of the product, and studied the physical-chemical properties and molecular structure changes of the product to explore the possible modification mechanism. The STPP not only improved the expansion characteristics of extrudates, but also increased the brightness of the extrudates, the rehydration rate. In addition, STPP increased the specific mechanical energy during extrusion, decreased the material mass flow rate. Furthermore, STPP decreased the starch digestibility, increased the content of slow-digesting starch and resistant starch. STPP increased the degree of denaturation of extrudate proteins, the proportion of β-sheets in the secondary structure of proteins, as well as the intermolecular hydrogen bonding interactions. The gelatinization degradation degree of starch molecules also decreased with the addition of STPP. STPP also increased the protein-starch interactions and enhanced the thermal stability of the extrudate. All these indicate that STPP can improve the physical-chemical properties of extrudate.

Design and Characterisation of Gentamicin Floating Microspheres as Potential Drug Carrier for the treatment of Intra-Abdominal Infection

Objective: The purpose of thecurrent research involves the design, development and characterization of Gentamicin floating microspheres to improve the residence time in the stomach without affecting, and contact with the gastric mucosa. Methods: Capillary extrusion technique used for the preparation of gentamicin floating microspheres by using sodium lauryl sulphate, sodium tripolyphosphate as a cross-linking agent, and chitosan as apolymer. After preparation, the surface morphology of microspheres was evaluated by the optical microscope and scanning electron microscope. Results: During this study, the effect of the stirring rate, polymer concentration and cross-linking concentration on the percent yield, in vitro floating behavior, and physical state of the incorporated drug, drug loading, and in-vitro drug releasewere examined. The prepared microspheres show prolonged drug release (twelve hours) and remained buoyant for more than eleven hours. The microspheres were found to be highly porous in nature and regular in shape. The Gentamicin release rate was found to be higher in the case of microspheres prepared at a higher agitation speed and decreased with increasing the polymer and cross-linking agent concentration. All formulations established favorable in vitro floating characteristics. The drug entrapment improved from 65.20 to 95.40%, by increasing polymer-to-drug ratio. The key release mechanism was found to be diffusion. it is observed that there is no significant changesin swelling ratio, % drug content, buoyancy lag time, or in vitro dissolution pattern after storage at accelerated stability condition for six months. Conclusion: Thus, the developed Gentamicin floating microspheres can demonstrate to be potential candidates for any intragastric conditions, as multiple-unit delivery systems areadaptable.