UV Spectrophotometry Research Articles

UV Spectrophotometry with Chemometric methods for Concurrent Assays of Antihypertensive Components in Tablets

Chemometrics is the precise and practice of analyzing data through various numerical techniques in order to develop useful information. Generally, it is better to measure many nonselective signals and then combine them in a multivariate model. Nowadays, the combinations of amlodipine, valsartan, and hydrochlorothiazide are effective antihypertensive drugs. The combination of active ingredients will be evaluated for its component content and validated using the chemometric spectrophotometric method paired with the multivariate partial least squares system. For modeling calibration and chemometric validation, a double divisor system was employed. An ultraviolet spectrophotometric measurement was performed by measuring the absorbance spectrum at a wavelength of 230-300nm of AML, 220-290nm of valsartan, and 230-300nm of hydrochlorothiazide at 2nm intervals. Partial Least Squares were used to calculate levels of AML is (99.59±0.28)%; VAL is (101.99± 0.44)% and HCT is (103.60±0.34)% and cross-validated using R2, PRESS, and RMSCEV. Concluded that the determination of amlodipine, valsartan, and hydrochlorothiazide mixtures by the partial least squares multivariate chemometric method met the requirements for tablet dosage forms, according to USP 43-NF38.

Determination of Progesterone in Pharmaceutical Preparations by UV, First-order Derivative Spectrophotometry and Gas Chromatography

The determination of progesterone in pure and capsule form was accomplished in this work using new, simple and quick procedures by UV spectrophotometry, first-order derivative spectrophotometry and gas chromatography. To increase the sensitivity of the suggested methods, it was necessary to optimize the solvent system, the detection wavelength, and the chromatographic conditions. The linear regression equations for the UV spectrophotometry, first-order derivative spectrophotometry and gas chromatography were y=0.0536x+0.0002, y=0.1362x+0.0014, and y=1.8217x-1.239, respectively, as determined by the least square regression approach. Under the chosen experimental conditions, no interference was found. The suggested methods are extremely accurate and precise. When the suggested methods' findings were compared to those of two published reference methods, there was statistically no discernible difference. Therefore, the methods are applicable to the measurement of progesterone in pharmaceutical formulations.

Simultaneous Estimation of Curcumin and Vitamin E in Bulk and Cosmeceutical Formulation by UV Spectrophotometry

The goal of present study is to validate the developed assay method per International Council for Harmonisation (ICH) Q2R1 recommendations and create a sensitive, reproducible, and practical method for detecting curcumin and Vitamin E in pure and in cosmeceutical formulations. With the creation and validation of a straightforward, accurate, and repeatable UV spectrophotometric method, curcumin and vitamin E in bulk and cosmeceutical formulation may now be determined simultaneously. The need for a new technique to estimate curcumin and vitamin E in a cosmeceutical formulation has become more pressing due to the lack of a well-described UV analytical method for doing so. Q absorption at 231 and 285 nm were used in the calculation. Vitamin E (16–24 μg/mL) and curcumin (8–12 μg/mL) both behave according to Beer-Lambert’s law at the designated wavelengths. The recovery experiments verified the method’s adherence to ICH standards for accuracy, precision, and resilience. The method under consideration can be employed to accurately determine the quantities of vitamin E and curcumin present in a cosmeceutical formulation

Deep eutectic solvents combined with beta-cyclodextrin derivatives for chiral separation of typical adrenergic receptor agonists by capillary electrophoresis with amperometric detection

Enantioseparation has always been one of the research hotspots and difficulties in the field of modern separation science. In this work, a binary chiral electrophoretic separation system was constructed using deep eutectic solvents (DESs) coupled with beta-cyclodextrin derivatives based on capillary electrophoresis with amperometric detection system, and five groups of typical adrenergic receptor agonists (adrenaline, salbutamol, isoproterenol, norepinephrine and terbutaline) were selected as the model enantiomers. The effects of additive types and contents of DESs and cyclodextrins, and the pH value and concentration of the running buffer on the resolution of the selected chiral compounds were investigated in detail. The mechanism of DESs improving separation was explored preliminarily by means of UV spectrophotometry, which was further verified based on the comparison of single and mixed components of choline chlorine-urea DES. Under the optimum conditions, the relative standard deviations for inter-day and intra-day repeatability of the migration time, peak area and resolution for adrenaline and salbutamol were within 8.7%, and the limits of detection reached 0.030 μg mL−1 (S/N = 3). The recovery data were in the range of 96.3–118.7%. The developed methods have been applied for the analyses of (+)-adrenaline hydrochloride injection and (±)-salbutamol aerosol. This binary chiral electrophoretic separation system by CE-AD has high detection sensitivity and low analytical cost, providing an alternative for the separation and analysis of chiral drugs.

Study on monomer functional suitability toward sofosbuvir in molecularly imprinted polymer: In silico and experimental study

Sofosbuvir (SOF) is an anti-HCV (Hepatitis C Virus) used as an off-label drug in treating COVID-19 and the usage requires good therapeutic drug monitoring, with analytical and suitable sample preparation methods. Therefore, this research aimed to apply in silico and laboratory testing in preparing SOF molecularly imprinted polymers (MIP). MIP is expected to improve sample preparation performance. The best functional monomer and porogen selection were determined through the use of Density Functional Theory (DFT) method with the B3LYP basis set 6–31G (d,p) and molecular dynamics simulation. The association constant test and Jobs plot were determined by the UV spectrophotometry and MIP synthesis method was conducted by bulk and precipitation polymerization. The polymer particles underwent characterization using Fourier-transform infrared spectroscopy and scanning electron microscopy. The result showed that methacrylic acid (MAA) and acetonitrile were the best functional monomer and porogen for synthesis. Precipitation polymerization yielded superior outcomes in terms of polymer homogeneity and adsorption capability compared to bulk polymerization. Polymer, MIP B, with a composition ratio of template:functional monomer:cross-linkers = 1:1:20, which was synthesized by the precipitation method, provided the best adsorption capability in all solvents tested, and had an imprinting factor of 1.15.

Imbalance of Plasma Copper and Zinc Levels and the Association Between the Cu/Zn Ratio and Lipid Peroxidation in Algerian Bipolar Patients.

Trace elements, through their interaction with biomolecules, can play an important role in the pathophysiology of bipolar disorder and protect against oxidative stress effects. The purpose of this study is to examine plasma concentration levels of zinc (Zn) and copper (Cu) of Algerian patients, diagnosed with bipolar disorder, and to compare these levels with those of healthy controls. The Cu/Zn ratio was calculated to explore a possible correlation between these elements and lipid peroxidation in the study groups. A total of 33 patients diagnosed with bipolar disorder and 38 healthy subjects participated in this study. Plasma copper and zinc concentrations were measured using a polarographic analyzer. The marker of plasma lipid peroxidation (Malondialdehyde:MDA) was determined by UV spectrophotometry. Plasma Cu concentrations were higher in patients compared to controls (p < 0.05), while the Zn level was significantly lower. Consequently, the Cu/Zn ratio was significantly different between patients and controls. Regarding MDA, no significant difference was noticed between the two study groups. However, in patients, a negative correlation was found between MDA and Cu/Zn ratio (r= -0.38, p= 0.027). These results suggested that an elevated Cu/Zn ratio is associated with attenuated lipid peroxidation in our bipolar patients.

Simultaneous Determination of Estradiol Cypionate and Medroxyprogesterone Acetate Hormones in Injectable Suspension by UV Spectrophotometry Based on Least-Squares Support Vector Machine and Fuzzy Inference System: Comparison with HPLC.

The combination of estradiol cypionate (ECA) and medroxyprogesterone acetate (MPA) is used to prevent pregnancy in women. The analysis of the ECA and MPA combination reveals a challenge due to the strong overlap of the spectra of these compounds. Spectrophotometry techniques along with chemometrics methods are simple, fast, precise, and low-cost for the simultaneous determination of ECA and MPA in a combined pharmaceutical dosage form. Two developed approaches, the least-squares support vector machine (LSSVM) and fuzzy inference system (FIS), along with a spectrophotometric method were proposed to solve such a challenging overlap. Based on the cross-validation method, the regularization parameter (γ) and width of the function (σ) in the LSSVM model were optimized and the root mean square error (RMSE) values were found to be 0.3957 and 0.2839 for ECA and MDA, respectively. The mean recovery values were 99.87 and 99.63% for ECA and MDA, respectively. The FIS coupled with principal component analysis (PCA) showed mean recovery percentages equal to 99.05 and 99.50% for ECA and MDA, respectively. Also, the RMSE of both components was lower than 0.3. The analysis results of a real sample (injection suspension) using the proposed methods were compared with HPLC by a one-way analysis of variance (ANOVA) test, and no significant differences were found in the results. Intelligent methods were proposed for the simultaneous determination of ECA and MPA. The least-squares support vector machine and fuzzy inference system along with spectrophotometry were used. HPLC as a reference method was performed and compared with chemometrics methods. The benefits of the proposed approaches are that they are rapid, simple, low-cost, and accurate.

A Carboxyethylchitosan Gel Cross-Linked with Glutaraldehyde as a Candidate Carrier for Biomedical Applications.

To date, few publications describe CEC's properties and possible applications-thus, further evaluation of these properties is a point of interest. The present in vitro model study aimed to evaluate a carboxyethylchitosan (CEC) gel with a degree of substitution of 1, cross-linked with glutaraldehyde at a polymer:aldehyde molar ratio of 10:1, as a potential carrier for delivering bacteriophages to various pH-fixed media (acidic, alkaline), and including gastrointestinal tract (GIT) variable medium. A quantitative analysis of bacteriophages released from the gel was performed using photon correlation spectrophotometry, and phage activity after emission into medium was evaluated using the spot test. The results showed that the CEC gel's maximum swelling ratios were at a nearly neutral alkaline pH. Increasing temperature enhances the swelling ratio of the gel independent from pH, up to 1127% at 37 °C and alkaline pH. The UV and photon correlation spectrophotometry showed equal gel release kinetics in both fixed media with acidic (pH = 2.2) and alkaline (pH = 7.4) pH environments at 37 °C, with the maximum release within two hours. However, phage lytic activity in the spot test during this simulation was absent. At the same time, we obtained an opaque phage lytic activity in the alkaline pH-fixed medium for at least three hours. Phages released from the tested CEC gel in different pHs suggest that this gel could be used for applications that require fast release at the treatment site both in acidic and alkaline pH. Such treatment sites could be a wound or even soil with mild acidic or alkaline pH. However, such CEC gel is not suitable as a delivery system to the GIT because of possible transported acid-sensitive agent (such as phages) release and destruction already in the stomach.

The Separation, Purification, Structure Identification, and Antioxidant Activity of Elaeagnus umbellata Polysaccharides.

In order to investigate the antioxidant activity of Elaeagnus umbellata polysaccharides, the physicochemical characteristics of purified Elaeagnus umbellata polysaccharides (EUP, consisting of two fractions, EUP1 and EUP2) were investigated using UV spectrophotometry, high-performance liquid chromatography (HPLC), high-performance gel permeation chromatography (HPGPC), and Fourier transform infrared spectroscopy (FT-IR). This revealed that EUP1 and EUP2 were acidic polysaccharides with an average molecular weight (MW) of 63 and 38 kDa, respectively. EUP1 mainly consisted of L-rhamnose and D-galactose in a molar ratio of 2.05:1, and EUP2 consisted of D-mannose, L-rhamnose, D-galactose, and D-arabinose in a molar ratio of 2.06:1:2.78:1. Furthermore, EUP exhibited considerable antioxidant potential for scavenging hydroxyl, superoxide anion, DPPH, and ABTS radicals. Therefore, EUP can be developed as a potential antioxidant for the functional food or pharmaceutical field.

5-Fluorouracil and Anti-EGFR antibody scaffold chitosan-stabilized Pickering emulsion: Formulations, physical characterization, in-vitro studies in NCL-H226 cells, and in-vivo investigations in Wistar rats for the augmented therapeutic effects against squamous cell carcinoma

This research seeks to optimize a chitosan-stabilized Pickering emulsion (PE) containing 5-fluorouracil (5-FU) as a potential Squamous Cell Carcinoma therapy. The 5-Fluorouracil was also thoroughly analysed using UV spectrophotometry and RP-HPLC, demonstrating exceptional linearity, sensitivity, precision, and robustness. The techniques of characterization revealed Pickering emulsion (PE) morphology, solid-like gel properties, successful encapsulation, and promising anticancer effects. FTIR was used to validate the efficacy of encapsulation, and DSC was used to confirm the post-encapsulation drug stability. The 0.6 % chitosan-stabilized PE showed exceptional stability and drug loading efficiency. Anti-EGFR-5-FU-CS-PE gel was developed for sustained drug release in the treatment of Squamous Cell Carcinoma. Anti-EGFR-5-FU-CS-PE demonstrated potent anticancer effects in vitro, with a lower IC50 than 5-FU and 5-FU-CS-PE. Anti-EGFR-5-FU-PE Pickering emulsions based on chitosan were investigated for their rheological properties, cellular interactions, and therapeutic potential. Both emulsions and gel exhibited sustained in vitro drug release after successful encapsulation. Anti-EGFR-5-FU-CS-PE induced apoptosis, decreased mitochondrial membrane potential, and inhibited the migration of cancer cells. Wistar mice were tested for safety and tumour growth inhibition. All formulations exhibited exceptional six-month stability. Anti-EGFR-5-FU-CS-PE emerges as a viable therapeutic option, necessitating additional research.

Effects of age and tissue of Juniperus sabina L. on its phytochemical characteristics, anti-cholinesterase, antidiabetes, and anti-drug resistant bacteria activities.

Juniperus sabina L. is used in the traditional Chinese medicine (TCM) system to prevent or treat various diseases. However, only the leaves and branches are used as medicinal parts. The aim of this study was to compare the chemical characteristics of different tissues (leaves, branches, stems, and roots) of J. sabina at different ages by HPLC-MS and to evaluate the biological activity (enzyme inhibition, anti-drug-resistant bacteria). Total phenol (TPC) and total lignan (TLC) contents in J. sabina were determined by Folin-Ciocalteu method and UV spectrophotometry, respectively. High levels of total phenols (87.16 mg GAE/g dry weight) and total lignans (491.24 mg PPT/g dry weight) were detected in fifteen annual J. sabina roots and current year leaves, respectively. Eleven compounds, of which six were phenolic compounds and five were lignans, were identified and quantified by HPLC/HPLC-MS. Statistical analysis showed that the distribution and content of the detected compounds showed considerable variation among ages and tissues, and that the current year leaves of fifteen annual J. sabina could be used as a potential application site for the source of podophyllotoxin. Acetylcholinesterase (AChE) inhibitory activity was found to be the highest on the extracts of fifteen annual J. sabina current year leaves (47.37 μg/mL), while the highest inhibition towards butyrylcholinesterase (BChE) was observed for the extracts of seven annual J. sabina previous year leaves (136.3 μg/mL). And the second annual J. sabina current year stem's extracts showed the best antidiabetic activity (anti-α-glucosidase, 62.59 μg/mL). In addition, the extracts of fifteen annual J. sabina roots (47.37 μg/mL) showed the highest anti-MRSA activity (31.25 μg/mL). Redundancy analysis (RDA) was conducted to clarify the factors affecting the biological activity of J. sabina, and its results showed that epicatechin and matairesinol showed positive promotion. This study provides a new perspective for understanding the chemical differences and comprehensive utilization of different tissues of J. sabina.

ANALYSIS OF INDIGENOUS BACTERIAL FLORA FOUND IN LEAD CONTAMINATED SOIL OF FAISALABAD AND HARVESTING ITS ABILITY FOR BIOREMEDIATION

Some microorganisms have the ability to either degrade or remove environmental pollutants and could serve an effective role in bioremediation. Lead is a chemically inert heavy metal and if present in toxic amount in environment, can have negative health effects by becoming a part of the natural food chain. The main objective of this experiment was to identify soil micrbiota present in Pb contaminated soil of Faisalabad. WHO has reported elevated levels of lead contamination in water, and air across major cities in Pakistan. It majorly affects children aged 3-5 years and the urban population residing in major cities in Pakistan. Major source of Pb exposure in Pakistan are industrial wastes and effluents discharged directly into environment and it has toxic effects on the human nervous, renal and reproductive systems. Molecular Docking via CB dock is performed taking some bacterial proteins as receptors molecules and lead salts as ligand molecule for insilico analysis of bacterial strain involved in biosorption or biotransformation process. To identify lead tolerant bacteria, soil samples were collected from Pb contaminated sites near Faisalabad, followed by inoculation and purification of bacterial colonies in lead nitrate based culture media. UV spectrophotometry was performed and the colony showing maximum growth rate was subjected to 16s rRNA and Phylogenetic analyses. The identified bacterial species possesses considerably high lead tolerance and further analyzed for potential lead biosorption capabilities.

A new approach for determination of orthophosphate based on mixed valent molybdenum oxide/poly 1,2-diaminoanthraquinone in seawater

Orthophosphate is an essential macronutrient in natural water that controls primary production and strongly influences the global ocean carbon cycle. Electrochemical determination of orthophosphate is highly recommended because electrochemistry provides the simplest means of determination. Here the determination of orthophosphate based on the formation of a phosphomolybdate complex is reported. Mixed-valent molybdenum oxide (MoxOy) was prepared by cyclic voltammetry on poly-1,2-diaminoanthraquinone (1,2-DAAQ), which was performed by cyclic voltammetry on the surface of a glassy carbon electrode under pre-optimized conditions for the thickness of the modified electrode layers. The proposed modified electrode was used for square-wave voltammetry of orthophosphate ions under pre-optimized square-wave parameters (i.e., frequency and amplitude) in strongly acidic medium (pH < 1). The linear range was 0.05–4 µM with a limit of quantification (LOD) of 0.0093 µM with no effect on two peaks due to cross interference from silicate. Furthermore, MoxOy/PDAAQ shows good reproducibility with a relative standard deviation (RSD) of 2.17% for the peak at 0.035 V and 3.56% for the peak at 0.2 V. Real seawater samples were also analyzed for PO43− analysis by UV spectrophotometry and the results were compared with the measurement results of our proposed electrode, with good recoveries obtained.

RP-HPLC Method Development and Validation for Estimation of Bisoprolol and Hydrochlorothiazide

The present study was to develop a rapid and sensitive method for the analysis of Bisoprolol and Hydrochlorothiazide by different analytical methods such as UV spectrophotometry and RP-HPLC in pharmaceutical dosage forms by using the most commonly employed C-18 column with UV-detection and validate it as per ICH guidelines. The retention time for Bisoprolol and Hydrochlorothiazide was found to be 2.1 min and 4.01 min respectively. A Resolution of greater than 2 was observed. The low % RSD values (≤ 2) indicated that the method was precise and accurate. The mean recoveries were found in the range of 99.1 – 99.9% w/w. Our approach was specific with good accuracy and precision when evaluating the commercial formulations without the interference of excipients and other additives. This method can be used to calculate the amounts of Bisoprolol and Hydrochlorothiazide in both single and mixed pharmaceutical formulations, as well as bulk samples.

A DFT theoretical and experimental study of the effect of indium doping within electrochemical deposited ZnO

The effect of indium doping within ZnO-NRs nanorods on FTO substrates was studied using integrated theory and experiments. The electrochemical deposited In-ZnO NRs were examined by X-ray diffraction (XRD), Scanning electron microscopy (SEM), UV–vis spectrophotometer, electrochemical cell, and Photocurrent spectroscopy. The obtained electronic and optical characteristics of the developed ZnO and In-ZnO films were validated by density functional theory (DFT) calculations using the TB-mBJ and PBE-GGA approximations. XRD patterns demonstrate that all electrodeposited films were crystalline having a hexagonal wurtzite with a preferred growth orientation (002). Furthermore, the crystallite particle size and (002) diffraction peak intensity of the samples reduces with In doping, suggesting a reduction in crystallinity with increasing indium. SEM images reveal a nicely defined hexagonal shape morphology of pure and In-doped ZnO nanorods, with an approximate mean diameter of ∼100 nm. UV spectrophotometry experiments and DFT calculations showed that the inclusion of In leads to a minor reduction in the optical gap energy. Mott-Schottky analysis displays an improvement in the conductivity attributed to an enhanced electronic injection in In-ZnO the conduction band, thus enhancing the photoelectrochemical properties of the zinc oxide film.

Synthesis, Characteristation and Biological Activity of Silver Nanoparticles Generated Using the Leaf and Stembark Extract of Combretum erythrophyllum.

Medicinal plants are known to contain numerous phytometabolites with suggested pharmacological value. Literature suggests that the medicinal use of phytometabolites in its natural state has limited success due to poor absorption rates. Currently, the focus lies on synthesizing phytometabolites extracted from medicinal plants and silver ions to generate nano-scale carriers with specialized properties. Thus, the nano-synthesis of phytometabolites with silver (Ag+) ions is proposed. The use of silver is promoted due to its known antibacterial and antioxidant effectiveness, among many. Nanotechnology allows for the green generation of nano-scaled particles that are able to penetrate target areas due to its size and unique structure. Therefore, this study aimed to generate a novel protocol for the synthesis of AgNP's using the leaf and stembark extracts of C. erythrophyllum. In addition, the biological activity of the generated nanoparticles was evaluated. To synthesis silver nanoparticles (AgNP's) using the leaf and stembark extracts of Combretum erythrophyllum. The relative shape, size, distribution, and zeta potential of the synthesised particles were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), Energy-dispersive X-ray (EDX), Nanoparticle tracking analysis (NTA), and UV Spectrophotometry (UV -vis). To screen the synthesised particles for its potential antibacterial, apoptotic and cytotoxic properties. A novel protocol for the synthesis of silver nanoparticles (AgNP's) using the leaf and stembark extracts of Combretum erythrophyllum was established. The generated AgNP's were characterised using transmission electron microscopy (TEM), scanning electron microscopy (SEM), Energy-dispersive X-ray (EDX), Nanoparticle tracking analysis (NTA), and UV Spectrophotometry (UV -vis). Furthermore, the AgNP's were evaluated for their antibacterial, cytotoxic and apoptotic activity against a range of bacterial strains and cancer cells. Characterisation was based upon particle size, shape and elemental silver composition. Within the stembark extract, synthesised nanoparticles were large, spherical in shape and dense in elemental silver composition. While synthesised nanoparticles of the leaf extract were small to medium in size, varied in shape established and contained minimal quantities of silver (substantiated by the TEM and NTA results). Furthermore, it was established that the synthesized nanoparticles exhibited high antibacterial properties due to the conducted antibacterial assay. The FTIR analysis revealed the presence of numerous functional groups within active compounds found in the synthesised extracts. Functional groups found varied between the leaf and stembark extracts, each with proposed pharmacological activity. Presently, antibiotic-resistant bacteria are continuously evolving thus, posing as a threat to conventional drug delivery systems. Nanotechnology provides a platform that enables the formulation of a low-toxicity and hypersensitive drug delivery system. Further studies evaluating the biological activity of extracts of C. erythrophyllum synthesized with silver nanoparticles could enhance its proposed pharmaceutical value.

Green synthesis of silver nanoparticles using extracts of Mikania cordata leaves and evaluation of their antioxidant, antimicrobial and cytotoxic properties

The synthesis of silver nanoparticles using plant extracts is a promising field of research due to the versatile biomedical application of metal nanoparticles. In the present study, silver nanoparticles (AgNPs) were synthesized using the aqueous extract of Mikania cordata leaves where extract act as both reducing and capping agents. Successful biosynthesis of AgNPs had been studied using UV Spectrophotometry that recorded the surface plasmonic resonance peak at around 451 nm. The structural properties and morphology of AgNPs were confirmed by scanning electron microscope with Energy dispersive X-ray (SEM/EDX), Fourier transform infrared (FT-IR) and X-ray diffraction (XRD) spectroscopic techniques. In antioxidant assays, AgNPs were found as strong free radical scavenger as ascorbic acid (standard) with the values of 10.06 (EC50, μg/mL) and 20.94 (EC50, μg/mL) for DPPH and ABTS radicals, respectively. In antimicrobial study, the effectiveness of synthesized AgNPs was observed as follows: Shigella boydii > Staphylococcus aureus > Shigella dysenteriae > Escherichia coli. Moreover, the results of cytotoxic assay indicated that AgNPs inhibited the growth of EAC cells in dose-dependent manner. Overall results of this study suggested that the synthesized AgNPs from Mikania cordata leaves have the merits to use in the field of nanomedicines.

Synthesis and Characterization of a Novel Zinc-Based Metal-Organic Framework Containing Benzoic Acid: A Low-Toxicity Carrier for Drug Delivery.

In recent years, metal-organic frameworks (MOFs) have gained attention in the biomedical field, particularly as drug carriers for treating tumors. Therefore, we decided to synthesize a novel benzoic acid Zn-based MOF and study the Zn-based MOFs' drug-delivery properties and the drug-delivery system's anticancer effects. This study successfully synthesized a zinc-based MOF using solvent thermal synthesis. The crystal structure of a Zn-based MOF was investigated using thermogravimetric analysis, X-ray diffraction, and Fourier transform infrared spectroscopy. Subsequently, the results of UV spectrophotometry showed that Doxorubicin was successfully loaded with a loading amount of 33.74%. Furthermore, the drug release experiments demonstrated that the Zn-based MOF was pH-sensitive, releasing more at a pH of 3.8 than at pH 5.8 or 7.4. Finally, the Zn-based MOF loaded with drugs exhibited high antitumor activity against HepG2 cells while demonstrating remarkably low toxicity to normal cells (LO2). Taken together, these results demonstrate that the Zn-based MOF has the potential to serve as a carrier in the field of drug delivery systems.

Effect of Freezing on Soybean Protein Solution.

To investigate the impact of frozen storage conditions on the physicochemical properties of soybean protein and explore the underlying mechanisms, this study focused on soybean isolate (SPI), ß-soybean companion globulin (7S), and soybean globulin (11S). The protein solutions were prepared at a concentration of 2% and subjected to freezing for 1 and 5 days. Subsequently, the protein content, physicochemical properties, secondary structure, sulfhydryl content, and chemical interaction forces were assessed and analyzed using UV spectrophotometry, Zeta potential measurements, SDS-PAGE, Fourier infrared spectroscopy, and endogenous fluorescence photoemission spectroscopy. The obtained results revealed that the solubility and total sulfhydryl content of SPI, 7S, and 11S exhibited a decreasing trend with prolonged freezing time. Among them, 11S demonstrated the largest decrease in solubility and total sulfhydryl content, followed by SPI, and 7S the least. During freezing, the aromatic amino acids of SPI, 7S, and 11S molecules were exposed, leading to increased hydrophobicity, protein aggregation, and particle size enlargement, and the structure of the protein changed from disordered structure to ordered structure. After freezing, the polarity of the microenvironment of SPI, 7S, and 11S increased, and their maximum fluorescence emission wavelengths were red-shifted. Notably, the largest red shift of SPI was from 332 nm to 335 nm. As freezing time increased, the contribution of hydrogen bonding increased, while the contribution of hydrophobic interactions decreased. This indicates that freezing affects the hydrophobic interactions, hydrogen bonding, and other chemical forces of the protein. The growth of ice crystals leads to the unfolding of protein molecular chains, exposure of internal hydrophobic groups, enhancement of hydrophobicity, and alters the secondary structure of the protein.

A mini review on the analytical method and its validation for Psidium guajava

The well-known tropical tree Psidium guajava, also known as the guava, is widely farmed for its fruit. This article consists of literature about various analytical techniques like TLC, UV spectrophotometry, HPLC, and HPTLC that could be used to analyze the Guava plant. The HPLC analysis of Quercetin isolated from the leaves of the guava plant uses a 4 x 125 mm Hypersil ODS column with a mobile phase of 0.5 percent ortho-phosphoric acid in water and methanol at a flow rate of 1ml/min. The column wash times are 20 min and 18 min, respectively. 250C is the temperature in the column. Silica gel 60F 254 pre-coated plates (10x10 cm) were used with toluene: acetone: formic acid (38:10:5) as the solvent system for HPTLC analysis of quercetin obtained from the tender leaves of guava. The λ max was observed in the U.V. spectrum of the isolated compound (quercetin) on three standard wavelengths: 212 nm, 256 nm, and 372 nm. An effort can be made to produce a new analytical method that will be cost-effective and time-saving.