The field of nanomedicine, utilizing nanoparticles for medical intervention, has captivated chemists and chemists alike over the past decades. Mesoporous silica nanoparticles have thrived into a leading contender in nanomedicine since their initial synthesis in the 1990s. This potential was further solidified in 2001 by Vallet-Regi et al.'s groundbreaking demonstration of their application in drug delivery. These nanoparticles possess unique properties, including a confined space ideal for encapsulating therapeutic compounds, which has spurred numerous research groups to develop MSN-based drug delivery systems. MSNs own exceptional properties like high surface area, finely tunable pore structures, and abundant silanol groups, enabling versatile functionalization inside and out. The breakthrough discovery of gated MSNs in the 2000s, particularly those functional in water, opened doors for developing sophisticated materials with stimuli-responsive molecular gates. Attached to the MSN surface, these gatekeepers act as nano valves, blocking cargo release until triggered by a specific chemical, biochemical, or physical stimulus, often cleaving the gate and unleashing the cargo. This precise control over cargo release empowers MSNs to function as efficient drug delivery systems, enhancing biocompatibility, cellular uptake, controlled release of drugs, targeted delivery, and therapeutic molecules. Gated MSNs have emerged as versatile tools with diverse biomedical applications beyond drug delivery. They can encapsulate and deliver various therapeutic agents like proteins, drugs, or genes for bioimaging and treatment modalities like radiotherapy, photothermal therapy, and tissue engineering. Their gated nature allows for controlled release triggered by specific stimuli, minimizing premature leakage and unwanted side effects. Additionally, gated MSNs extend beyond medicine, finding applications in sensing and communication due to their unique properties. Due to their unique chemical properties, nanomaterials offer the potential to be designed for various applications. This has created numerous MSNs with diverse compositions, structures, and functionalities. These MSNs have shown promising cytotoxicity, therapeutic efficacy, and biocompatibility results. For comprehensive details on the Synthesis of MSNs, refer to the extensive review by Croissant et al. Unlike unmodified materials that suffer from premature drug release , surface-modified silica nanocarriers offer significant protection, enabling controlled delivery via various stimuli like pH, temperature, enzymes, and magnetic fields. The differing pH ranges across tissues and organs make pH-responsive systems particularly effective. The weakly acidic environment found in many tissues serves as an ideal trigger for targeted drug release , highlighting the potential of pH-responsive MSN for numerous biomedical needs, including anticancer therapy , gastrointestinal and ocular drug delivery and even gene therapy. This approach ensures the drugs reach their intended destination and release their therapeutic effect at the precise time and location, maximizing their efficacy while minimizing potential side effects.