BR-102020026454-B1 - Bacterial nanocellulose membrane and its use as a bolus in radiotherapy.

Abstract

BACTERIAL NANOCELLULOSE MEMBRANE AND ITS USE AS A BOLUS IN RADIOTHERAPY. The present invention describes a bacterial nanocellulose (BNC) membrane, obtained from the cultivation of a strain of Komagataeibacter rhaeticus in Hestrin-Schramm medium. Physicochemical analyses demonstrated that the described membrane has a pure, highly hydrated, homogeneous, and nanostructured network of cellulose fibers, and possesses superior Radiological Density (RD) and Radiation Attenuation Potential (PAR) similar to commercially available boluses. Moldability analysis showed that the membrane has a profile identical to a virtual bolus, thus validating its use as a highly efficient biotechnological device, aligned with the idea of sustainability, as a bolus to be used in radiotherapy. The invention described solves identified technical problems, such as poor adhesion of the device to the irradiated area, enabling the effective application and delivery of planned dosages.

Inventors

• Hernane Da Silva Barud
• AMANDA MARIA CLARO
• ANDRÉ CAPALDO AMARAL
• CREUSA SAYURI TAHARA AMARAL
• FERNANDO PEREIRA VANNI
• GIULIA CRISTINA CHIOZZINI
• GUILHERME PAULÃO MENDES
• HÉLIDA GOMES DE OLIVEIRA BARUD
• NAYARA CAVICHIOLLI DO AMARAL

Assignees

• BIOSMART NANOTECHNOLOGY LTDA
• ASSOCIAÇÃO SÃO BENTO DE ENSINO

Dates

Publication Date

20260317

Application Date

20201222

Claims (3)

1. 1. METHOD FOR OBTAINING BACTERIAL NANOCELLULOSE MEMBRANE characterized by being obtained from the cultivation of Komagataeibacter rhaeticus in Hestrin-Schramm medium, composed of D-glucose, yeast extract, magnesium sulfate, monobasic potassium phosphate, 99.8% alcohol and distilled water, in a circulating air oven at 28°C for 7 days, and treated with a 0.1 M sodium hydroxide solution at 70°C.
2. 2. USE OF BACTERIAL NANOCELLULOSE MEMBRANE, obtained as described in claim 1, characterized by being used as a bolus in radiotherapy.
3. 3. USE OF BACTERIAL NANOCELLULOSE MEMBRANE, according to claim 2, characterized by being for radiotherapy procedures in the treatment of superficial tumors.

Description

BRIEF DESCRIPTION [001] This patent application concerns a “BACTERIAL NANOCELLULOSE MEMBRANE AND ITS USE AS A BOLUS IN RADIOTHERAPY”, which refers to a bacterial nanocellulose (BNC) membrane, obtained from the cultivation of a strain of Komagataeibacter rhaeticus, to be used as a bolus in radiotherapy procedures. The physicochemical analyses performed demonstrated that the described membrane has a pure, highly hydrated, homogeneous, and nanostructured network of cellulose fibers, in addition to having superior Radiological Density (RD) and Radiation Attenuation Potential (PAR) similar to commercially available boluses. The moldability analysis demonstrated that the membrane presents a profile identical to the virtual bolus. Therefore, the present invention has been validated for use as a highly efficient biotechnological device, aligned with the idea of sustainability, as a bolus to be used in radiotherapy. FIELD OF APPLICATION [002] The present invention belongs to the human needs section, to the health field, to the radiation therapy field, as it is a bacterial nanocellulose (BNC) membrane, obtained from the cultivation of a strain of Komagataeibacter rhaeticus, to be used as a bolus in radiotherapy procedures. CONVINCING [003] Boluses are materials designed to homogenize and surface doses of ionizing radiation and correct imperfections in the areas to be irradiated. They are materials equivalent to human tissue, made from various materials and customized in a way, and are placed in direct contact with the patient's skin in order to protect and preserve tissues and organs from undesirable doses of radiation (Nakamura and Prado, 2016: Use of the bolus as an auxiliary device in radiotherapy treatment). This type of material is characterized by having an attenuation coefficient of electromagnetic radiation similar to biological tissue, with the purpose of restricting the penetration of high-energy photons and electrons used in radiotherapy for the treatment of superficial tumors. [004] Often, the adhesion of the bolus to the patient's skin is not perfect, resulting in the formation of spaces and air bubbles between the bolus layer and the area due to surface irregularities. This influences the planned dose distribution and can cause unpredictable variations between the planned dose and the actual dose administered. Therefore, the more perfect the adhesion of the bolus to the area to be irradiated, the better the dose distribution in the target volume, improving the accuracy of the radiotherapy treatment (Gonçalves, 2017: Design and production of individualized boluses via three-dimensional printing for external radiotherapy). [005] In this context, the present invention is included, which describes a bacterial nanocellulose (BNC) membrane, obtained from the cultivation of a strain of Komagataeibacter rhaeticus, to be used as a bolus in radiotherapy procedures, considering the development of new materials, mainly from sustainable biotechnological routes and contributing to increasing the efficiency and expanding the use of these technologies. [006] With estimates of over 1.2 million cases worldwide (Bray et al., 2018: Global cancer statistics 2018: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries), skin cancer is currently the most common malignant neoplasm, and its incidence is increasing, mainly due to the main risk factor: high exposure to ultraviolet light (Chummun, 2017: The management of malignant skin cancers). This type of cancer can be divided into two main groups: non-melanoma skin cancer, which includes basal cell and squamous cell carcinomas, and melanoma. The first type has a good prognosis and the neoplasms are derived from epidermal cells, while the second type is derived from melanocytes and has a much higher risk of metastasis (Craythorne and Al-Niami, 2017: Skin cancer). [007] There is a variety of cancer treatments, with local surgical excision being the standard for managing most patients. However, radiotherapy plays a key role, especially in cases of non-melanoma skin cancer in clinically inoperable areas or in areas where surgery leads to poor functional and/or aesthetic outcomes, such as eyelids, nasal tips and wings, and lips. Therefore, radiotherapy for these cases takes into account antecedents that include the tumor location and activity in that region (Mierzwa, 2019: Radiotherapy for Skin Cancers of the Face, Head, and Neck). [008] In the treatment of superficial tumors with radiation, electrons, low-energy photons, or high-energy photons are most commonly used. In some cases, it is necessary to superficialize the therapeutic dose with the use of a bolus, a material equivalent to human tissue, flexible and whose composition is not altered by high doses of radiation (Vyas et al., 2013: On bolus for megavoltage photon and electron radiation therapy). Thus, the use of a bolus leads to an increase in the attenuation of photons above the skin, ensu