Recent Advances in Polymer Nanocomposites: Unveiling the Frontier of Shape Memory and Self-Healing Properties-A Comprehensive Review.

Shape memory and self-healing polymer nanocomposites have attracted considerable attention due to their modifiable properties and promising applications. The incorporation of nanomaterials (polypyrrole, carboxyl methyl cellulose, carbon nanotubes, titania nanotubes, graphene, graphene oxide, mesoporous silica) into these polymers has significantly enhanced their performance, opening up new avenues for diverse applications. The self-healing capability in polymer nanocomposites depends on several factors, including heat, quadruple hydrogen bonding, π-π stacking, Diels-Alder reactions, and metal-ligand coordination, which collectively govern the interactions within the composite materials. Among possible interactions, only quadruple hydrogen bonding between composite constituents has been shown to be effective in facilitating self-healing at approximately room temperature. Conversely, thermo-responsive self-healing and shape memory polymer nanocomposites require elevated temperatures to initiate the healing and recovery processes. Thermo-responsive (TRSMPs), light-actuated, magnetically actuated, and Electrically actuated Shape Memory Polymer Nanocomposite are discussed. This paper provides a comprehensive overview of the different types of interactions involved in SMP and SHP nanocomposites and examines their behavior at both room temperature and elevated temperature conditions, along with their biomedical applications. Among many applications of SMPs, special attention has been given to biomedical (drug delivery, orthodontics, tissue engineering, orthopedics, endovascular surgery), aerospace (hinges, space deployable structures, morphing aircrafts), textile (breathable fabrics, reinforced fabrics, self-healing electromagnetic interference shielding fabrics), sensor, electrical (triboelectric nanogenerators, information energy storage devices), electronic, paint and self-healing coating, and construction material (polymer cement composites) applications.

Analytical challenges in detecting microplastics and nanoplastics in soil-plant systems.

Microplastics (MPx) and nanoplastics (NPx) are increasingly accumulating in terrestrial ecosystems, heightening concerns about their potential adverse effects on human health via the food chain. Techniques aimed at recovering the most challenging colloidal fractions of MPx and NPx, especially for analytical purposes, are limited. This systematic review emphasises the absence of a universal, efficient, and cost-effective analytical method as the primary hindrance to studying MPx and NPx in soil and plant samples. The study reveals that several methods, including density separation, organic matter removal, and filtration, are utilized to detect MPx or NPx in soil through vibrational spectroscopy and visual identification. Instruments such as Pyrolysis Gas Chromatography Mass Spectrometry (Py-GCMS), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR) Spectroscopy, and fluorescence microscopy are employed to identify MPx and NPx in plant tissue. In extraction procedures, organic solvents and sonication are used to isolate NPx from plant tissues, while Pyrolysis GC-MS quantifies the plastics. SEM and TEM serve to observe and characterize NPx within plant tissues. Additionally, FTIR and fluorescence microscopy are utilized to identify polymers of MPx and NPx based on their spectral characteristics and fluorescence signals. The findings from this review clarify the identification and quantification methods for MPx and NPx in soil and plant systems and provide a comprehensive methodology for assessing MPx/NPx in the environment.

Covalent organic frameworks-based smart materials for mitigation of pharmaceutical pollutants from aqueous solution.

Covalent organic frameworks (COFs) are an emergent group of crystalline porous materials that have gained incredible interest in recent years. With foreseeable controllable functionalities and structural configurations, the constructions and catalytic properties of these organic polymeric materials can be controlled to fabricate targeted materials. The specified monomer linkers and pre-designed architecture of COFs facilitate the post-synthetic modifications for introducing novel functions and useful properties. By virtue of inherent porosity, robust framework, well-ordered geometry, functionality, higher stability, and amenability to functionalization, COFs and COFs-based composites are regarded as prospective nanomaterials for environmental clean-up and remediation. This report spotlights the state-of-the-art advances and progress in COFs-based materials to efficiently mitigate pharmaceutical-based environmental pollutants from aqueous solutions. Synthesis approaches, structure, functionalization, and sustainability aspects of COFs are discussed. Moreover, the adsorptive and photocatalytic potential of COFs and their derived nanocomposites for removal and degradation of pharmaceuticals are thoroughly vetted. In addition to deciphering adsorption mechanism/isotherms, the stability, regeneratability and reproducibility are also delineated. Lastly, the outcomes are summed up, and new directions are proposed to widen the promise of COF-based smart materials in diverse fields.

Comparative study of adjuvant chemotherapeutic efficacy of docetaxel plus cyclophosphamide and doxorubicin plus cyclophosphamide in female breast cancer.

PURPOSE: This retrospective study presents a comparative analysis of the overall survival and toxicities, as side effects, of docetaxel plus cyclophosphamide (TC) and doxorubicin plus cyclophosphamide (AC). The study measured their efficacies during adjuvant chemotherapy, treating Pakistani breast cancer patients by validating the results obtained, with the published analysis of the same treatment given to US patients. PATIENTS AND METHODS: Between June 2015 and September 2017, for four chemotherapy cycles, 189 patients out of 358 received TC (75 mg/m2 of docetaxel, 600 mg/m2 of cyclophosphamide) and 169 were treated with AC (60 mg/m2 of doxorubicin, 600 mg/m2 of cyclophosphamide). On the basis of using pathological markers to assess patients, toxicities, as side effects, (due to docetaxel, doxorubicin, and cyclophosphamide) were listed in the database of this study. Common factors with respect to common terminology criteria for adverse events version 5.0 and side effects listed in MedlinePlus, NIH US database, and from the database of this study were then separated to be included in comparison for this study. Statistically, chi-squared test was used at α=0.05. RESULTS: There was no statistically significant difference between the proportions of patients with vomiting, extreme tiredness, diarrhea, mild anemia, stability, and overall survival because P-value >0.05. However, AC remained less toxic (P-value <0.05) by 22.6%, 25.7%, 25.3%, 12.4%, 20.8%, and 16.4% compared to TC for changes in taste, muscle pain, burning hands, change in hemoglobin level, moderate anemia, and needing blood transfusion respectively, whereas TC remained less toxic by 52.9%, 32.5%, and 26.3% for dizziness, weight loss, and sores in throat and mouth, respectively. CONCLUSION: At 27 months, TC was more toxic than AC, whereas both combinations had the same overall survival rate.

Seroprevalence of hepatitis B and hepatitis C in health care workers in Abbottabad.

BACKGROUND: Hepatitis B and C viruses (HBV & HCV) are hepatotropic viruses causing viral hepatitis, chronic liver disease and hepatocellular carcinoma. Modes of infection are more or less similar. HBV is vaccine preventable while HCV is not. They are prevalent in different parts of the world including Pakistan. The rate of prevalence varies from region to region and among different population segments. The present study was planned to see the prevalence of HBV & HVC among health care workers in various hospitals of Abbottabad. METHOD: The study was conducted at the District Headquarter Teaching Hospital Abbottabad over a period of one year on 125 health care workers of different categories and either sex. Brief history was taken from each individual and physical examination was performed. Blood samples were taken for HBV and HC serology. Positive sera were confirmed by 3rd generation ELISA. RESULTS: As much as 8% individuals were positive for HBV or HCV. HBV alone was seen in 3 out of 10 (30%) individuals. HCV alone was also found in 3 out of 10 (30%) individuals. HBV and HCV co-infection was seen in 4 out of 10 (40%) individuals. Dental procedures, needle prick and surgical procedures were found the common risk factors. Blood transfusion was known in 2 out of 10 (20%) individuals. Family history of hepatitis was not positive in any individual. CONCLUSION: Results of the present study differ from those of the previous studies conducted on health care workers in Pakistan.

Pharmacokinetic evaluation of quetiapine fumarate controlled release hybrid hydrogel: a healthier treatment of schizophrenia.

The current study aimed to rationally develop and characterize pH-sensitive controlled release hydrogels by graft polymerization of gelatin (Gel) and hydroxypropyl methyl cellulose (HPMC) in the presence of glutaraldehyde (GA) using quetiapine fumarate for the treatment of schizophrenia. The prepared hydrogels discs were subjected to various physicochemical studies including: swelling, diffusion, porosity, sol-gel analysis, Fourier transform infrared spectroscopy, differential scanning calorimetry, and scanning electron microscopy. Three different pH values (1.2, 6.8 and 7.4) were used to determine shape, transition, and controlled release behavior of prepared hydrogels. Various kinetic models including zero order, first order, Higuchi model and Power Law equation were applied on drug release data. The optimized hydrogels were subjected to in vivo studies using albino rabbits. Swelling and release results were found to be insignificant (p < .05) evidencing that there was no significant difference in swelling and drug release rate of hydrogels in different pH mediums. Swelling, porosity, gel-fraction, and drug released (%) were found to be dependent on concentrations of Gel, HPMC, and GA. Kinetic models revealed that QTP-F release followed non-Fickian diffusion. In-vivo studies contributed significantly higher plasma QTP-F concentration (Cmax), time for maximum plasma concentration (Tmax), area under the curve (AUC0-inf) and half-life (t1/2) as 18.32 ± 0.50 µg/ml, 8.00 ± 0.01 hrs, 6021.2 ± 5.09 µg.hrs/ml and 10.06 ± 0.43 hrs, respectively, for test-hydrogels when compared to reference market brand (Qusel® 200 mg, Hilton Pharma, Karachi, Pakistan) QTP-F tablets. It might be concluded that QTP-F loaded pH-sensitive hydrogels were developed successfully with reduced dosing frequency for schizophrenia.