Facile one-step targeted immobilization of an enzyme based on silane emulsion self-assembled molecularly imprinted polymers for visual sensors.

Immobilized enzymes play significant roles in many practical applications. However, the enzymes need to be purified before immobilization by conventional immobilizing methods, and the purification process is expensive, laborious, complicated and results in a decrease of the enzymatic activity. So, we present a novel method by a facile one-step targeted immobilization of an enzyme without a purification process from complex samples. For this purpose, a novel molecularly imprinted polymer was prepared via a silane emulsion self-assembly method using boric acid-modified Fe3O4 nanoparticles as magnetic nuclei, horseradish peroxidase as a template, 3-aminopropyltriethoxysilane as a functional monomer and tetraethyl orthosilicate as a crosslinking agent. The molecularly imprinted polymers were characterized using a scanning electron microscope, X-ray photoelectron spectroscope, vibrating sample magnetometer and X-ray diffractometer. The as-prepared and characterized materials were employed to immobilize horseradish peroxidase from a crude extract of horseradish. Moreover, the immobilized horseradish peroxidase was employed to develop visual sensors for the detection of glucose and sarcosine. This study demonstrated that the molecularly imprinted polymers prepared via the silane emulsion self-assembly method can facilely immobilize horseradish peroxidase from a crude extract of horseradish without any purification process. The developed visual method based on the immobilized horseradish peroxidase shows great potential applications for the visual detection of glucose and sarcosine.

Hemin-porous g-C3N4 hybrid nanosheets as an efficient peroxidase mimic for colorimetric and visual determination of glucose.

A method is described for colorimetric determination of glucose by using hemin-porous graphitic carbon nitride (g-C3N4) hybrid nanosheets as a peroxidase mimic. The porous g-C3N4 nanosheets were prepared by a combination of one-pot self-polymerization, pyrolysis and liquid-phase exfoliation. The hemin-porous g-C3N4 hybrid nanosheets were prepared via in-situ deposition. It is shown that the hybrid composite has improved dispersibility, stability, and peroxidase-mimicking activity in the 3,3',5,5'-tetramethylbenzidine (TMB)/H2O2 system. This is deemed to be the result of the synergistic effect of hemin and porous g-C3N4 nanosheets. Based on these advantages of the nanosheets, a simple, low-cost, sensitive and selective colorimetric method was established for the determination of glucose at pH values around 7. Best performed at a wavelength of 652 nm, the assay has a linear response in the 10.0 µM to 500 µM glucose concentration range (R2 = 0.9942) and a 1.94 µM limit of detection. This method was successfully applied to the determination of glucose in (spiked) human serum samples. In our perception, the hybrid is a robust peroxidase mimic for use in POx-based assays as needed in medical diagnosis and environmental analysis. Graphical abstract Schematic presentation of the process of hemin-porous g-C3N4 hybrid nanosheets catalyzing the oxidation of peroxidase chromogenic substrate tetramethylbenzidine (TMB) in the presence of H2O2. The material was applied in colorimetric and visual determination of H2O2 and glucose.

Moisturizing effect of stable cream containing Crocus sativus extracts.

The present study is about to prepare stable cream of water-in-oil emulsion containing extracts of Crocus sativus against its base (without extracts) taken as control, to determine its stability on different storage conditions and effects on skin moisture contents and transepidermal water loss. The formulation contains 3% Crocus sativus (Saffron) concentrated extracts, and the base containing no extract, were formulated. Different stability tests were done on samples, which placed at 8°C, 25°C, 40°C and 40°C with 75% relative humidity, for 4 week period. These formulations (Creams) were applied on the cheeks of human volunteers for 8week period. To evaluate any effect produced by these formulations different skin parameters were monitored every week. The significant results of this study explored the fact that water-in-oil emulsion topical cream of saffron formulated from Crocus sativus extract has absolute physical stability at different storage conditions. The increase in skin moisture contents and changes in transepidermal water loss were significant (p<0.05) with respect to base and formulation respectively. Topical cream of Crocus sativus showed significant moisturizing effects on human skin.

Effect of pharmaceutical promotion and incentives offered by pharmaceutical companies on the prescribing pattern of medical students: a cross-sectional study from a developing nation Pakistan.

Background: Pharmaceutical companies continuously pursue healthcare professionals, starting from the medical college level, which can ultimately lead to irrational prescribing of drugs and antibiotics. Therefore, our main aim was to evaluate the opinions and attitudes of medical students toward pharmaceutical promotion. Methods: This study utilized a cross-sectional online survey that applied the snowball sampling technique. Data were collected from three public and three private sector medical colleges in Punjab, Pakistan using snowball sampling. A modified version of a pre-structured questionnaire was used to collect data between October 2020 and January 2021. Medical students from the third year onward were captivated. The tool was made available on Google Forms and students could access it by clicking the link shared. The effect of promotion on prescribing pattern and future prescribing of antibiotics were measured. Descriptive statistics, chi-square, and t-test were used to analyze the data. Results: A total of 1,301 students filled out the survey, but only 1,227 responses were acceptable. The average age was found to be 23.4 ± 1.59 years. Slightly more than half of the respondents were male participants (57.7%), and a significant proportion (84.1%) reported being aware of pharmaceutical promotion. A smaller number (27.7%) felt that physicians who meet medical representatives more frequently tend to prescribe more antibiotics and 46.3% indicated they would be willing to prescribe antibiotics under the promotional influence. Medical students who were male, in senior college years, attended government institutions, and had lower parental income showed significantly higher perception and attitude scores (p < 0.05) which, in turn, may show their inclination to promotional activities. Many students agreed with the view that pharmaceutical promotion (PP) activities may alter prescribing practices and also believed that they contribute to the increased irrational prescribing of drugs and antibiotics. Conclusion: The study revealed that only a small number of students are willing to engage in promotional activities and accept rewards, which influences their choice toward selection of drugs and antibiotics. This study highlighted the necessity of giving proper educational instructions regarding the promotion of drugs to medical students. This study also focused on the educational prerequisites of the students.

Dispensing of antibiotics for tuberculosis patients using standardized patient approach at community pharmacies: results from a cross-sectional study in Pakistan.

Background: Pakistan is among top countries for antibiotic consumption around the globe and patients often receive antibiotics directly from community pharmacies. Thus, our aim was to assess the drug dispensing practices of pharmacies for presumed and confirmed tuberculosis by using standardized patients' method in Pakistan. Methods: In this cross-sectional study, we adopted two standardized patient cases in pharmacies of three cities of Punjab. The first case involved a presumed tuberculosis patient presenting with 2-3 weeks of cough and fever (Case-1), and the second case involved a confirmed tuberculosis patient carrying microbiologically confirmed tuberculosis results (Case-2). The ideal management for Cases-1 and Case-2 is referral of standardized patients to a healthcare provider without dispensing antibiotics or steroids, or both. The differences in antibiotic use, steroid use, and the number of medicines dispensed in referred and non-referred patients between Case-1 and Case-2 were analyzed using descriptive statistics. Results: Between April 1, 2020, and July 31, 2020, standardized patients completed 575 out of 598 interactions among community pharmacies in Lahore, Rawalpindi, and Sialkot. We recorded ideal management in 115 (37.7%) of the 305 Case-1 interactions and 130 (48.1%) of the 270 Case-2 interactions. Antibiotic dispensing was higher in Case-1, with 71 out of 305 instances (23.3%), than in Case-2 interactions, with 27 out of 270 instances (10.0%). Anti-tuberculosis drugs were dispensed to 1 patient in Case-1 (0.3%) and to 19 patients (7.0%) in Case-2. Conclusion: Slightly more than one-third of pharmacies in Punjab, Pakistan, ideally managed patients with presumed tuberculosis, but almost half of them ideally managed cases of confirmed tuberculosis. The presence of confirmed diagnosis slightly changes the behavior in the correct management of patients.

Methacrylic functionalized hybrid carbon nanomaterial for the selective adsorption and detection of progesterone in wastewater.

Progesterone, an endocrine-disrupting chemical, has been frequently detected in wastewater for decades, posing a serious threat to ecological and human health. However, it is still a challenge to achieve the effective detection of progesterone in complex matrices water samples. In this study, a novel adsorbent CNT@CS/P(MAA) was prepared by grafting methacrylic polymers on the surface of modified carbon nanomaterials. Compared with other reported materials, the hybrid carbon nanomaterial could selectively identify the progesterone in the complex industrial pharmaceutical wastewater, and its adsorption performance is almost independent of the pH and environmental temperature. In addition, this nanomaterial could be reused with a good recovery rate. The prepared nanomaterials were characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, nitrogen adsorption and desorption experiments, and thermogravimetric analysis. The results confirmed that the methacrylic polymers and chitosan layer were successfully grafted on the surface of carbon nanotubes. Adsorption isotherms, adsorption kinetics, and selectivity tests showed that CNT@CS/P(MAA) had a high adsorption capacity (44.45 mg·g-1), a fast adsorption rate and a satisfied selectivity for progesterone. Then, CNT@CS/P(MAA) was used as solid phase extraction sorbent and combined with HPLC to enrich progesterone from the wastewater samples. Under the optimum conditions, a good linearity was obtained with the correlation coefficient was 0.9998, and the limit of detection was 0.003 ng·mL-1. Therefore, this method could be used for the selective and effective detection of progesterone in industrial wastewater with complex substrates and provided a new method for the detection of progesterone in other environmental waters.

Awareness and Attitudes of the Pakistani Population With Regard to Physician-Pharmaceutical Company Interaction: A Cross-Sectional Study.

Objective: To determine the awareness and attitudes of the Pakistani population regarding physician-pharmaceutical company interactions. Methods: The data were collected from primary health care clinics and pharmacy outlets located within cities of six randomly selected districts of the Punjab Province. Those individuals (age ≥18 years) who have just completed their visit to the physician and well understand Urdu language were approached. Descriptive analysis was performed for all variables by using SPSS (IBM version 26). Results: A total of 3,852 participants fully completed the study out of 4,301 (response rate 89.5%). Of those, 30.9% were female; two-thirds (66.7%) were aware of drug representatives' visits to clinics. The majority were aware of pharmaceutical company material presence (or absence) in the physicians' rooms (56.6%), company items with logos (66.8%), patient education materials (73.4%), and 60.8% thought that receiving gifts from companies was "wrong/unethical" practice for physicians, which was lower in comparison to other professions such as judges to accept gifts from lawyers (65.6%) and professional sports umpires to acknowledge gifts (64.3%). A minority said that they have lower trust on physicians for using drug company notepads or pens (16.7%), going on trips sponsored by the company (16.7%), accepting gifts <15,000 PKR (90.3 US$) (26.7%), and accepting gifts >15,000 PKR (90.3 US$) (40.0%). Conclusion: Survey participants were well aware of physician-pharmaceutical company interactions. Participants were more knowledgeable regarding the pharmaceutical company presence (or absence) in physicians' offices than about gift-related practices of physicians. Trust on the physician was not affected by small gifts but by the large gifts.

Preparation of magnetic metal organic framework and development of solid phase extraction method for simultaneous determination of fluconazole and voriconazole in rat plasma samples by HPLC.

Fluconazole and voriconazole are the two broad-spectrum triazole antifungals. The present work described the fabrication method for the synthesis of the amino-modified magnetic metal-organic framework. This material was applied as a pre-sample treatment sorbent for the selective extraction of fluconazole and voriconazole in rat plasma samples. The material was fabricated by the chemical bonding approach method and was characterized by different parameters. The factors which affect the extraction efficiency of the sorbent material were also optimized in this study. Due to the optimization of solid-phase extraction conditions, the nonspecific interaction was reduced and the extraction recoveries of target drugs were increased in plasma samples. The extraction method was combined with the HPLC-UV method for the analysis. Excellent linearity (0.1-25 µg/mL), detections (0.02, 0.03 µg/mL) and quantification limits (0.04, 0.05 µg/mL) were resulted for fluconazole and voriconazole respectively. The maximum recoveries from spiked plasma samples of fluconazole and voriconazole were 86.8% and 78.6% and relative standard deviation were 0.9-2.8% and 2.2-3.6% respectively. Moreover, this sorbent material was used multiple times which was an improvement over single-use commercial sorbent materials. This validated method has practical potential for the simultaneous determination of these drugs in therapeutic drug monitoring studies as well as for routine pharmacokinetic evaluations.

Development of Surface Molecularly Imprinted Polymers as Dispersive Solid Phase Extraction Coupled with HPLC Method for the Removal and Detection of Griseofulvin in Surface Water.

Griseofulvin (GSF) is clinically employed to treat fungal infections in humans and animals. GSF was detected in surface waters as a pharmaceutical pollutant. GSF detection as an anthropogenic pollutant is considered as a possible source of drug resistance and risk factor in ecosystem. To address this concern, a new extraction and enrichment method was developed. GSF-surface molecularly imprinted polymers (GSF-SMIPs) were prepared and applied as solid phase extraction (SPE) sorbent. A dispersive solid phase extraction (DSPE) method was designed and combined with HPLC for the analysis of GSF in surface water samples. The performance of GSF-SMIPs was assessed for its potential to remove GSF from water samples. The factors affecting the removal efficiency such as sample pH and ionic strength were investigated and optimized. The DSPE conditions such as the amount of GSF-SMIPs, the extraction time, the type and volume of desorption solvents were also optimized. The established method is linear over the range of 0.1-100 µg/mL. The limits of detection and quantification were 0.01 and 0.03 µg/mL respectively. Good recoveries (91.6-98.8%) were achieved after DSPE. The intra-day and inter-day relative standard deviations were 0.8 and 4.3% respectively. The SMIPs demonstrated good removal efficiency (91.6%) as compared to powder activated carbon (67.7%). Moreover, the SMIPs can be reused 10 times for water samples. This is an additional advantage over single-use activated carbon and other commercial sorbents. This study provides a specific and sensitive method for the selective extraction and detection of GSF in surface water samples.

On-Line two dimensional liquid chromatography based on skeleton type molecularly imprinted column for selective determination of sulfonylurea additive in Chinese patent medicines or functional foods.

Substandard and counterfeit anti-diabetic medicines directly influence the health and impose a great danger to individual patients and to public health. Counterfeiting has become a serious and underreported problem in the pharmaceutical industry. There are a large number of counterfeit medicines flooded in anti-diabetic markets which effect human health directly and indirectly. Therefore, some novel analytical techniques are necessary to be established for detecting these counterfeit drugs. In this study, a novel skeleton type molecularly imprinted column was successfully prepared. Based on the column, a simple, fast and reliable two-dimensional chromatography analytical system was established for selective determination of the illegal sulfonylurea additive in traditional Chinese patent medicines and functional foods. The developed method was validated. The linearitiesof the method were tested with calibration curves using ten calibration points in the concentration range of 0.25-12.5µg/g. The LODs were 0.0125µg/g and 0.01µg/g for tolbutamide and glibenclamide respectively. The five batches of Chinese patent medicines and dietary supplements obtained from different markets and online websites were tested by the validated method. With good retention time and spectral confirmation, chemical anti-diabetic substances were identified and quantified in traditional Chinese medicine and in dietary supplements.