In this century, the development of nanotechnology is projected to be the establishment of a technological evolutionary of this modern era. Recently, nanotechnology is one of the most active subjects of substantial research in modern material sciences and hence metal nanoparticles have a great scientific interest because of their unique optoelectronic and physicochemical properties with applications in diverse areas such as electronics, catalysis, drug delivery, or sensing. Nanotechnology provides an understanding on fundamental properties of objects at the atomic, molecular, and supramolecular levels. Besides, nanotechnology also leads an alternative technological pathway for the exploration and revolution of biological entities, whereas biology provides role models and biosynthetic constituents to nanotechnology. The findings of this review are important to provide an alternative for the green synthesis of silver nanoparticles. It showed more cost-effective and environmental friendly application as well as easier for large production, with relation to the properties of silver nanoparticles as antimicrobial, can be served well as an alternative antiseptic agent in various fields. Typically, silver nanoparticles are smaller than 100 nm and consist of about 20–15,000 silver atoms. Due to the attractive physical and chemical properties of silver at the nanoscale, the development of silver nanoparticles is expanding in recent years and is nowadays significant for consumer and medical products.

Eyesight is one of the most well-deserved blessings, amid all the five senses in the human body. It captures the raw signals from the outside world to create detailed visual images, granting the ability to witness and gain knowledge about the world. Eyes are exposed directly to the external environment; they are susceptible to the vicissitudes of diseases. The World Health Organization has predicted that the number of individuals affected by eye diseases will rise enormously in the next decades. However, the physical barriers of the eyes and the problems associated with conventional ocular formulations are significant challenges in ophthalmic drug development. This has generated the demand for a sustained ocular drug delivery system, which serves to deliver effective drug concentration at a reduced frequency for consistent therapeutic effect and better patient treatment adherence. Recent advancement in pharmaceutical dosage design has demonstrated that a stimuli-responsive in situ gel system exhibits the favorable characteristics for providing sustained ocular drug delivery and enhanced ocular bioavailability. Stimuli-responsive in situ gels undergo a phase transition (solution–gelation) in response to the ocular environmental temperature, pH, and ions. These stimuli transform the formulation into a gel at the cul de sac to overcome the shortcomings of conventional eye drops, such as rapid nasolacrimal drainage and short contact time with the ocular surface This review highlights the recent successful research outcomes of stimuli-responsive in situ gelling systems in treating in vivo models with glaucoma and various ocular infections. Additionally, it also presents the mechanism, recent development, and safety considerations of stimuli-sensitive in situ gel as the potential sustained ocular delivery system for treating common eye disorders.

An optimal host–microbiota interaction in the human vagina governs the reproductive health status of a woman. The marked depletion in the beneficial Lactobacillus sp. increases the risk of infection with sexually transmitted pathogens, resulting in gynaecological issues. Vaginal infections that are becoming increasingly prevalent, especially among women of reproductive age, require an effective concentration of antimicrobial drugs at the infectious sites for complete disease eradication. Thus, topical treatment is recommended as it allows direct therapeutic action, reduced drug doses and side effects, and self-insertion. However, the alterations in the physiological conditions of the vagina affect the effectiveness of vaginal drug delivery considerably. Conventional vaginal dosage forms are often linked to low retention time in the vagina and discomfort which significantly reduces patient compliance. The lack of optimal prevention and treatment approaches have contributed to the unacceptably high rate of recurrence for vaginal diseases. To combat these limitations, several novel approaches including nano-systems, mucoadhesive polymeric systems, and stimuli-responsive systems have been developed in recent years. This review discusses and summarises the recent research progress of these novel approaches for vaginal drug delivery against various vaginal diseases. An overview of the concept and challenges of vaginal infections, anatomy and physiology of the vagina, and barriers to vaginal drug delivery are also addressed.

The eyes are the window to the world and the key to communication, but they are vulnerable to multitudes of ailments. More serious than is thought, corneal infection by herpes simplex viruses (HSVs) is a prevalent yet silent cause of blindness in both the paediatric and adult population, especially if immunodeficient. Globally, there are 1.5 million new cases and forty thousand visual impairment cases reported yearly. The Herpetic Eye Disease Study recommends topical antiviral as the front-line therapy for HSV keratitis. Ironically, topical eye solutions undergo rapid nasolacrimal clearance, which necessitates oral drugs but there is a catch of systemic toxicity. The hurdle of antiviral penetration to reach an effective concentration is further complicated by drugs’ poor permeability and complex layers of ocular barriers. In this current review, novel delivery approaches for ocular herpetic infection, including nanocarriers, prodrugs, and peptides are widely investigated, with special focus on advantages, challenges, and recent updates on in situ gelling systems of ocular HSV infections. In general congruence, the novel drug delivery systems play a vital role in prolonging the ocular drug residence time to achieve controlled release of therapeutic agents at the application site, thus allowing superior ocular bioavailability yet fewer systemic side effects. Moreover, in situ gel functions synergistically with nanocarriers, prodrugs, and peptides. The findings support that novel drug delivery systems have potential in ophthalmic drug delivery of antiviral agents, and improve patient convenience when prolonged and chronic topical ocular deliveries are intended.

The susceptibility of aphids to lauric acid, a type of middle-chain fatty acids, based pesticide formulation was investigated. The insecticidal properties of lauric acid based pesticide formulation against aphids were evaluated through the three main routes of exposure: topical application, leaf-dipping (ingestion) and inhalation. Surface tension dependent aphids toxicity was also investigated by measuring the surface tension value of each formulation prepared. The relationship of surface tension and formulation toxicity was then observed on aphid tested. The obtained results indicate that all tested formulations had insecticidal activity against tested aphids depending on exposure method and lauric acid concentration. The topical application method recorded 100% mortality rates compared to the other two methods. With topical application method, most of the aphids died soon after treatment. Toxicity symptoms from lauric acid to aphids included unusual abdominal contractions which caused quick loss of coordination and decreased activity, and finally dehydration and necrosis within 24 hours. Results from surface tension study revealed close connection between toxicity and surface tension. This might lead to the conclusion that toxicity was possibly related to aphid suffocation in the highly wettable solution. Results from this research also demonstrated that there were possibility that lauric acid do not only kill aphids by suffocation, but also through change of cuticle and cell permeability and desiccation that lead to speedy death due to the chemical nature of lauric acid. Overall, the results recommend that lauric acid based pesticide formulation has both physical and chemical mode of action on aphids