Recent advances in carbon quantum dots for gene delivery: A comprehensive review.

Gene therapy is a revolutionary technology in healthcare that provides novel therapeutic options and has immense potential in addressing genetic illnesses, malignancies, and viral infections. Nevertheless, other obstacles still need to be addressed regarding safety, ethical implications, and technological enhancement. Nanotechnology and gene therapy fields have shown significant promise in transforming medical treatments by improving accuracy, effectiveness, and personalization. This review assesses the possible uses of gene therapy, its obstacles, and future research areas, specifically emphasizing the creative combination of gene therapy and nanotechnology. Nanotechnology is essential for gene delivery as it allows for the development of nano-scale carriers, such as carbon quantum dots (CQDs), which may effectively transport therapeutic genes into specific cells. CQDs exhibit distinctive physicochemical characteristics such as small size, excellent stability, and minimal toxicity, which render them highly favorable for gene therapy applications. The objective of this study is to review and describe the current advancements in the utilization of CQDs for gene delivery. Additionally, it intends to assess existing research, explore novel applications, and identify future opportunities and obstacles. This study offers a thorough summary of the current state and future possibilities of using CQDs for gene delivery. Combining recent research findings highlights the potential of CQDs to revolutionize gene therapy and its delivery methods.

New spectrophotometric and smartphone-based colorimetric methods for determination of atenolol in pharmaceutical formulations.

Novel spectrophotometric and smartphone-based colorimetric methods were developed and validated for the estimation of atenolol (ATE) in pharmaceutical formulations. The measurement procedure is based on the de-diazotization reaction, in which ATE is able to inhibit the diazotized sulfanilic acid from reacting with 8-hydroxy quinoline (8-HQ) in a basic medium. As a result, the formation of red-orange color azo-dye is hindered, and the color intensity is decreased proportionally to concentration of ATE. In spectrophotometric method the azo-dye color fate was monitored at 495 nm. While in smartphone-based colorimetric (SBC) method the captured image in the design processed by RGB App and transferred to the absorbance. The reactant concentrations were optimized using a central composite design (CCD) and response surface method. The methods exhibit good linearity in the 8.0 to 60.0 µg mL-1 range with no significant effect of interferences. The spectrophotometric method yields a linear equation with a slope of 0.0187 (R2 = 0.9993), a limit of detection (LOD) of 1.28 µg mL-1, and a limit of quantification (LOQ) of 4.28 µg mL-1. On the other hand, the smartphone-based colorimetric (SBC) method demonstrates a linear equation with a slope of 0.0127 (R2 = 0.9965), an LOD of 2.13 µg mL-1, and an LOQ of 7.09 µg mL-1. Analyzing ATE in pharmaceutical tablets was utilized to validate the applicability of the developed methods, and the results were statistically compared with those obtained by the HPLC method using the t-test and F-test.

The Advances in Chitosan-based Drug Delivery Systems for Colorectal Cancer: A Narrative Review.

Colorectal cancer (CRC) is considered a lethal cancer all around the world, and its incidence has been reported to be increasing. Chemotherapeutic drugs commonly used for treating this cancer have shown some drawbacks, including toxicity to healthy cells and non-precise delivery. Thus, there is a necessity for discovering novel diagnostic and therapeutic options to increase the survival rate of CRC patients. Chitosan, as a natural polymer, has attracted a lot attention during the past years in different fields, including cancer. Studies have indicated that chitosan-based materials play various roles in prevention, diagnosis, and treatment of cancers. Chitosan nanoparticles (NPs) have been shown to serve as anti-cancer agents, which provide sustained drug release and targeted delivery of drugs to the tumor site. In this paper, we review available literature on the roles of chitosan in CRC. We discuss the applications of chitosan in designing drug delivery systems as well as anti-cancer activities of chitosan and involved signaling pathways.

A carbon-based fluorescent probe (N-CDs) encapsulated in a zeolite matrix (NaFZ) for ultrasensitive detection of Hg (II) in fish.

In this work, a novel strategy was addressed to fabricate new sensing probe (N-CDs@NaFZ) from nitrogen doped carbon dots (N-CDs) confined in Al-free ferrisilicates zeolite (NaFZ) by hydrothermal/solvothermal method. The probe was systematically characterized by HR-TEM, FTIR, energy dispersive X-ray (EDX), powder X-ray diffraction, and UV-Vis absorption and fluorescence spectrophotometers. Characterization of the designed nanocomposite template N-CDs@NaFZ by fluorescence spectrum demonstrates a variety of important conducts as stability improvements, reasonable dispersibility in water, highly emission intensity enhancement at 435 nm when excited at 340 nm, excitation independent fluorescence behaviors, great quantum yield percentage of 91.2%, and narrow size distribution 12 nm, as a nano-space confinement effect of zeolite effectively increase the rigidity of N-CDs. Based on the fluorescence quenching mechanism, the designed approach exhibits an excellent selectivity and good sensitive response to the presence of Hg(II) ions under ambient temperature, with a wide linear range of 0.1-1500 nM and lower detection limits of 5.5 pM. Influences of variables pH and incubation time were optimized. The N-CDs@NaFZ sensor was effectively applied for the detection of Hg(II) ions in the farmed and wild rainbow trout fishes, and the results are in reasonable agreement when compared with that obtained by the cold vapor atomic absorption method.

Sensitive colorimetric aptasensor based on g-C3N4@Cu2O composites for detection of Salmonella typhimurium in food and water.

A new colorimetric aptasensor equipped with a novel composite of graphitic carbon nitride (g-C3N4) nanosheets and copper oxide(I) (Cu2O) nanocrystals is presented for Salmonella typhimurium (S .typhimurium). The dual-purpose structure of this composite simultaneously contributes to superb peroxidase-like activity and interaction with a label-free aptamer. Although g-C3N4@Cu2O effectively creates a visible blue color following the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) in presence of hydrogen peroxide (H2O2), this catalytic activity of the composite severely decreases after the interaction with aptamers. In the presence of S. typhimurium in sample, aptamers bound to their specific target. Subsequently, g-C3N4@Cu2O catalytic activity was enhanced in proportion to S. typhimurium concentration. Under optimized conditions, this aptasensor exhibited an excellent detection performance in a range from 1.5 × 101 to 1.5 × 105 CFU/ml, with a detection limit of 15 CFU/ml. Besides, portable detection of S. typhimurium by paper-based model of this method operated successfully in just 6 min. Analysis of spiked milk samples revealed high potential of this method as a sensitive, rapid, and label-free promising tool for S. typhimurium detection. A novel composite of g-C3N4 nanosheets and Cu2O nanocrystals was constructed through this study, which represented a collection of significant properties for designing an aptasensor. The simultaneous capability of this composite for peroxidase-like activity and interaction with aptamer led to design a fast accurate biosensor for detecting as low as 15 CFU/ml Salmonella typhimurium as one of the most important foodborne pathogens which is a persistent burden for societies.

A highly sensitive fluorescent immunosensor for sensitive detection of nuclear matrix protein 22 as biomarker for early stage diagnosis of bladder cancer.

A novel strategy is reported for highly sensitive, rapid, and selective detection of nuclear matrix protein NMP22 using two-color quantum dots based on fluorescence resonance energy transfer (FRET). Quantum dots (QDs) are highly advantageous for biological imaging and analysis, particularly when combined with (FRET) properties of semiconductor quantum dot (QDs) are ideal for biological analysis to improve sensitivity and accuracy. In this FRET system narrowly dispersed green emitting quantum dot CdTe core is used as a donor and labelled by monoclonal (mAb) antibody, while orange emitting quantum dot CdTe/CdS core shell is used as an accepter and labelled by polyclonal (pAb) antibody. The quantum dots are labelled by antibodies using EDC/NHS as crosslinking agent. Bovine serum albumin (BSA) solution was added to block nonspecific binding sites. The fluorescence intensity of QDs accepter decreased linearly with the increasing concentrations of NMP22 from 2-22 pg mL-1 due to FRET system and fluoroimmunoassay reaction. This method has good regression coefficient (R 2 = 0.998) and detection limit was 0.05 pg mL-1. The proposed FRET-based immunosensor provides a quick, simple and sensitive immunoassay tool for protein detection, and can be considered as a promising approach for clinical applications. The proposed FRET-based immunosensor provides a quick, simple and sensitive immunoassay tool for protein detection, and can be considered as a promising approach for clinical applications.