It is generally known that polymeric NPs (PNPs) are “colloidal macromolecules” with a particular structural architecture made of several monomers [28]. Synthetic and natural polymers are utilized to prepare polymer NPs, which constitute a substantial class of drug delivery vehicles [48]. Polymer NPs are a versatile delivery system for a wide range of compounds, including as tiny chemicals, proteins, genes, and chemotherapeutic medicines. Poly (alkyl cyanoacrylate) (PACA), poly-caprolactone (PCL), polyanhydrides, polyethyleneimine (PEI), chitosan, gelatin, and polylactic acid (PLA) are just a few of the polymer NPs that are being studied in the lab. To accomplish controlled drug release in the target, the drug is either encapsulated or bonded to the exterior of NPs, forming a nanosphere or a nanocapsule [30, 56].

In recent Ginsenoside Rg5, a triterpene saponin derived from the herbal ginseng plant, has been shown recently to be among the most effective anticancer medications against several types of carcinoma cells. Rg5’s poor bioavailability, nontargeted administration, and low solubility in water, however, limit its therapeutic potential. In order to increase Rg5’s therapeutic efficacy and tumor targetability, researchers created folic acid (FA) modified bovine serum albumin (BSA) NPs (FA-Rg5-BSA NPs) [57].

For the oral delivery of QC, polymeric nanoparticulate systems from PLGA-TPGS (Qu-NPs) were used, and the anticancer impact of this formulation on TNBC was assessed both in vitro and in vivo. Qu-NPs have a good drug loading capacity (8.1 ± 0.4%) and a homogeneous spherical morphology, with a mean diameter of 198.4 ± 7.8 nm. Additionally, Qu-NPs showed noticeably better inhibition of TNBC cell growth and metastasis. After oral gavage, 4T1-bearing mice showed a strong anticancer impact of Qu-NPs with a tumor inhibition ratio of 67.88% and fewer lung metastatic colonies [58].

To combat breast cancer cells, Kumari et al. [59] created NPs of curcumin and PGMD (poly-glycerol-malic acid-dodecanedioic acid). NPs with an entrapment efficiency range of 75–81% were synthesized by combining two different ratios of PGMD polymer with curcumin: CUR NP 7:3 and CUR NP 6:4. The MCF 7 and MDA-MB-231 breast cancer lines were used for the scratch test and in vitro anticancer activities. At 48 hours, the CUR NP 7:3 and CUR NP 6:4 nanoformulations each had an IC50 of 40.2 μM and 33.6 μM, respectively, in the MCF-7 cell line; in the MDA-MB-231 cell line, the corresponding values were 43.4 μM and 30.5 μM. Assays using acridine orange/EtBr and DAPI labeling revealed apoptotic characteristics and nuclear abnormalities in the cells that were treated. Western blot study further supported this by showing that curcumin has a function in apoptosis via upregulation of caspase 9 [59].

These are phospholipid monolayer, emulsifier, and water-based colloidal nanocarriers, with a size range of 1–100 nm. These are referred to as nanomaterials with zero dimensions. Triglycerides, fatty acids, waxes, steroids, and PEG are examples of the lipid component [31]. Lipids have been proposed as an alternate carrier to circumvent these drawbacks of polymeric NPs, especially for lipophilic drugs. SLNs are a class of lipid NPs that are gaining a lot of attention from formulators all over the world [32].

The cancer burden is rising rapidly worldwide, and it annually causes about 8.8 million deaths worldwide. Due to chemical drugs’ side effects and the emergence of resistance, the development of new green drugs has received much attention. We aimed to investigate whether solid-lipid NPs containing essential oil of Zataria multiflora (ZMSLN) enhanced the anticancer efficacy of the essential oil against breast cancer (MDA-MB-468) and melanoma (A-375) cells [60].

Studies on podophyllotoxin-based SLNs with epidermal targeting mechanisms have also been published. The findings showed that podophyllotoxin-based SLN preparations aided in drug penetration via the stratum corneum and hair follicle routes [61].

To target HT-29 cells for the therapy of colon cancer, the generated SLNs were further conjugated with FA. Even after coating chitosan on the surface of SLN, the optimization method yields the least amount of particle size (174 ± 5 nm). When compared to the uncoated formulation (25 μg mL^–1), the chitosan-coated formulation shows greater cytotoxicity against HT-29 cells at a dosage of 10 μg mL^–1. The medication is delivered by folate receptor-mediated endocytosis, which may be the cause of the increased cytotoxicity in FA conjugation. The techniques of western blot and fluorescence labeling were employed to verify the high-affinity binding of the folate receptor. The enhanced drug absorption and death in Ht29 cells are revisited with the aid of flow cytometry [3].

These are spherical vesicles that contain pharmacological molecules encapsulated in phospholipids, which can be either unilamellar or multilamellar [62]. Liposomes have distinctive properties, including minimal intrinsic toxicity, minimal immunogenicity, and biological inertness [63]. Following its description in 1965, the first closed bilayer phospholipid structures, known as liposomes, were quickly suggested as methods of delivering drugs. Significant technological advancements including remote drug loading, extrusion for homogeneous size, long-circulating (PEGylated) liposomes, triggered release liposomes, liposomes containing nucleic acid polymers, ligand-targeted liposomes, and liposomes containing drug combinations were made possible by the groundbreaking work of innumerable liposome researchers over the course of nearly five decades [64]. Because of their increased anti-tumor efficaciousness and improved absorption, liposomes offer a great vehicle for the administration of drugs including doxorubicin (Dox), PTX, and nucleic acid [65].

Liposomal-based phytochemical formulations have become more and more popular in recent years. Deshmukh et al. [66] employed chitosan and lecithin in an electrostatic deposition-assisted film hydration method to form a liposomal nanosystem that protected the flavone chrysin, also called 5,7-dihydroxyflavone, which is present in passion flowers, honey, propolis, Passiflora caerulea and Passiflora incarnata, and Oroxylum indicum, within the nanolipoidal shell [66].

This study investigates the effects of liposomal NP-delivered QC on the metabolism of mycophenolic acid (MPA) in combination therapy (impeding MPA metabolic rate). Both QC liposome NPs (QC-LNPs) and MPA liposome NPs (MPA-LNPs) were produced separately and thoroughly described. MPA-LNPs and QC-LNPs that were produced were measured to have sizes of 183 ± 13 and 157 ± 09.8, respectively [67].

Spherical polymeric macromolecules with a well-defined hyperbranched topology are called dendrimers. Dendrimers are characterized by highly branching architectures [68]. Dendrimers typically have a size between 1 nm and 10 nm. Still, the size could be as much as 15 nm. A path to synthetic target molecules with spherical shapes, distinct surface chemistries, and sizes that correspond to virus particles is provided by the dendrimer chemistry described. The biggest aim is a generation 13 dendrimer made up of triazines connected by diamines, which is stable in the presence of additives and at different concentrations, pH levels, temperatures, and solvent polarity ranges [69].

A family of structurally defined macromolecules known as dendrimers has a central core, a high-density exterior that is terminated with surface functional groups, and a low-density inner made up of repeating branching units. Unlike their polymeric cousins, dendrimers are symmetrically structured and nanoscale particles that can be mass-produced in a reproducible manner using monodispersity technology [70].

For targeted applications, ursolic acid and FA were coupled with PAMAM dendrimer. The FA improves cellular absorption by targeting the folate receptor from HepG2 cells. The PAMAM dendrimer facilitates the cytotoxic action of ursolic acid and exhibits electrostatic absorptive qualities that assist attract HepG2 cells. PAMAM dendrimer is a potentially useful carrier for the targeted delivery of phytochemicals [71].

Colloidal NPs with heterogeneous mixes of an oil droplet in aqueous media with a diameter ranging from 10 nm to 1,000 nm are known as nanoemulsions [40]. Advanced melanoma can be treated with a nanoemulsion of rapamycin, bevacizumab, and temozolomide [72]. In contrast to liposomes, nanoemulsions exhibit superior qualities, including stability, optical clarity, and biodegradability. In both cellular and animal models, the chosen medication combination loaded in IL shown encouraging results, most likely by influencing various mechanisms involved in tumor proliferation, dissemination, and angiogenesis. Future research would examine the impact of changing the chemical makeup of the nanoemulsion [73].

NEs have been used in the codelivery of several anticancer medications to increase the medications’ therapeutic efficacy and bioavailability. Mice with SKOV3 cancer were given a combination of PTX and curcumin in the form of a nanoemulsion by Ganta S and Amiji M. When PTX was given to mice treated with curcumin in nanoemulsion form, the AUC increased by 4.1 times. PTX’s relative bioavailability was 5.2 times higher, which enhanced the drug’s accumulation in cancer tissues by 3.2 times [74].

As the name implies, carbon NPs are based on the element carbon. Since they are biocompatible and have optical, mechanical, and electrical qualities, they have been used extensively in the medical field [75]. The most promising options for various applications are the graphene family of nanomaterials because of their distinct intrinsic qualities, which are valued in their straightforward molecular design and their capacity to function in harmony with other nanomaterials already in existence [76]. Via differentiation-based nanotherapy, graphene oxide may be a useful non-toxic therapeutic approach for eliminating cancer stem cells [77]. A novel family of carbon compounds known as fullerenes (formerly buckminsterfullerenes) was first identified in 1985 [78]. If fullerene (Cm) is deposited in the tumor tissue, it should have a photodynamic effect on the tumor since it efficiently produces singlet oxygen when exposed to light [79].

Due to its low bioavailability, curcumin, a popular natural substance used in anticancer therapy, cannot reach its full potential. We further assessed the in vivo performance and in vitro properties of SWCNT-Cur, building on our earlier study of a new curcumin delivery system utilizing functionalized single-walled carbon nanotubes via phosphatidylcholine and polyvinylpyrrolidone (SWCNT-Cur). In mice, SWCNT-Cur dramatically raised the blood content of curcumin up to an eighteen-fold increase [78, 80]. Figure 2 depicted the mechanism of herbal NPs to target the cancer stem cells and release of natural drug.

Since metallic NPs have exceptional optical, magnetic, and photothermal capabilities, they are frequently investigated in “biological imaging” and targeted DDS. The most widely utilized metallic NPs include copper, silver, iron-based, and gold NPs. Because the size and surface characteristics of gold NPs are easily manipulated, they are exploited as intracellular targeted drug carriers [81]. The multidisciplinary topic of nanotechnology pertains to the engineering and design of items with a size less than 500 nanometers (nm). The National Cancer Institute has acknowledged that major advancements in cancer diagnosis and therapy can be achieved using nanotechnology, which presents an amazing and transformative opportunity. Nanotechnology has been researched and developed during the past few decades, mostly for application in cutting-edge medicine delivery systems [82]. Most cancer-related deaths are caused by metastases. Treatment of metastases presents distinct challenges because to their tiny size, high multiplicity, and dispersion into various organ settings [83].

Another naturally occurring alkaloid that is derived from a variety of plants, including Canzptotheca acirminata and Mappia foetida, is camptothecin. By specifically targeting topoisomerase I, an enzyme involved in the relaxation of DNA supercoils, this drug exhibits strong antitumor efficaciousness [84].

In Asia, ginseng (Panax ginseng) root is a common traditional medication. Ginseng consumption prior to a cancer diagnosis raised the overall survival rate for patients with breast cancer. Consuming P. ginseng improved several elements of the physical and mental functioning of patients with gynecologic or hepatobiliary cancer in another randomized placebo-controlled experiment. Furthermore, European mistletoe, or Viscum album, is another often recommended cancer treatment. Up to 2003, this plant extract was the subject of about 23 clinical investigations, 19 of which produced encouraging findings regarding the quality of life, survival, and tumor suppression of cancer patients [53].

Semiconductor quantum dots (QDs) are light-emitting, nanoscale particles with special optical and electronic characteristics. These include the capacity to simultaneously excite multiple fluorescent colors, improved signal brightness, and stability of the fluorescent signal [68]. In cultivated HeLa cells, quantum dots labeled with the protein transferrin underwent receptor-mediated endocytosis, while dots labeled with immunomolecules identified certain antibodies or antigens [85]. The features of semiconducting quantum dots are highly uncommon; these particles are in the nanometer range. Band gaps in the quantum dots depend intricately on several aspects that are outlined in the article [86]. A new family of inorganic fluorophores known as QDs is becoming more well-known due to its remarkable photophysical characteristics [87]. A targeted cancer imaging, treatment, and sensing system utilizing QD-aptamer (Apt)-Dox conjugate [QD-Apt(Dox)] [88].

C-dots (aqueous fluorescent) of turmeric, black pepper, cinnamon, and red chili were made using a one-pot green synthesis process and subsequently subjected to an in vitro analysis. Human kidney cells (HK-2) and human glioblastoma cells (LN-229) were revealed to be more cytotoxic in cytotoxicity assays [89].

MRI imaging often uses magnetic NPs, and medication delivery involves metal or metal oxides [90]. Lipid-based gene transfection techniques and magnetic NPs were used to induce active Fas expression in breast cancer cells. Human Fas and GFP-expressing plasmid DNA (pDNA) was transfected into MCF-7 breast cancer cells [91]. When the tissues were injected with LHRH-SPIONs, the contrast enhancement of conventional T2 images acquired from the tumor tissue and of mice bearing breast cancer xenograft is demonstrated to be significantly greater than that in saline controls [92]. Breast cancer xenografts and lung metastases were also observed to have improved MRI contrast in magnetic anisotropy multi-CRAZED images of tissues taken from animals treated with SPIONs [93, 94]. For the targeted treatment of oral squamous cell carcinoma, combining thermal ablation with antibody-targeting magnetic NPs is a viable treatment option [95].

The curcumine-loaded folate-grafted magnetic NPs have strong inhibitory effects on MCF-7 breast cancer cells and KB nasopharyngeal carcinoma cells. The NPs demonstrated targeted thermo-chemotherapy resulting in apoptosis by selectively interacting with the folate receptor, which is overexpressed in cancer cells, according to the magnetic effect [96].

Derived from Artemisia annua, it is patented for its anti-cancer and anti-inflammatory properties [143].

Patents for curcumin analogs that have improved solubility and efficacy against various cancers [144, 145].

Extracted from herbs like Ganoderma lucidum (Reishi mushroom) and patented for their immunomodulatory and anti-cancer properties [146, 147].