Preparation and characterization of [68Ga]NODAGA-Pamidronic acid for pet bone cancer imaging
Early detection of bone metastases is essential to prevent skeletal-related events. Unlike biopsies, a non-invasive technique to diagnose bone metastases is by utilizing radiopharmaceuticals and detected using a nuclear imaging modality. Hence, this research deems to determine the role of gallium...
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| Format: | Thesis |
| Language: | English |
| Published: |
2020
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| Online Access: | http://psasir.upm.edu.my/id/eprint/104367/ http://psasir.upm.edu.my/id/eprint/104367/1/ZARIF%20NAIM%20MOHD%20ASHHAR%20-%20IR.pdf |
| _version_ | 1848864270507311104 |
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| author | Mohd Ashhar, Zarif Naim |
| author_facet | Mohd Ashhar, Zarif Naim |
| author_sort | Mohd Ashhar, Zarif Naim |
| building | UPM Institutional Repository |
| collection | Online Access |
| description | Early detection of bone metastases is essential to prevent skeletal-related
events. Unlike biopsies, a non-invasive technique to diagnose bone metastases
is by utilizing radiopharmaceuticals and detected using a nuclear imaging
modality. Hence, this research deems to determine the role of gallium-68
radiolabeled bisphosphonates ([68Ga]NODAGA-Pamidronic acid) for PET bone
cancer imaging. This study aims to ascertain the preparation, characterization,
and radiolabeling of [68Ga]NODAGA-Pamidronic acid. Lastly, to determine its
potential application, the in vitro bone binding assay and in vivo bone-to-blood
ratio is examined. Firstly, NODAGA-Pamidronic acid (NODPAM) was prepared
via the NHS ester conjugation method and characterized using tandem mass
spectrometry (MS/MS). The RP-HPLC method was then developed to remove
the free NODAGA using 0.1% trifluoroacetic acid and water as the mobile phase
at a flow rate of 0.5 ml/ min. Based on the MS/MS analysis of NODPAM, the
precursor ion and product ion observed were according to the theoretical value
(theoretical [M-H]-m/z: 591.14, obtained [M-H]-m/z: 591.14, [M-H-H3PO3]-m/z:
509.17). The isotopic abundance M+1 (calculated m/z: 22.02, obtained m/z:
20.99±0.94) confirms the molecular formula C18H34N4O14P2. The HPLC method
developed shows a good separation between peaks with a resolution of 1.613.
The freeze-dried NODPAM produces a solid white powder. Next, the
radiolabeling of [68Ga]NODPAM was optimized by looking into three parameters;
pH, temperature, and amount NODPAM. Finally, the in vitro bone binding assay
and in vivo bone-to-blood ratio was determined using synthetic hydroxyapatite
and Sprague Dawley rats, respectively. From the results obtained, the %RCP of
radiolabeled [68Ga]NODPAM was above 90% within 15 minutes at pH 4-4.5 and
a temperature of above 60ºC. The in vitro hydroxyapatite (HA) bone binding
assay displayed a significant difference between the [68Ga]NODPAM
82.25%±1.72 and [99mTc]MDP of 53.21%±0.28 (p<0.05). The bone-to-blood ratio
of [68Ga]NODPAM 2-hour post-injection was significantly higher (P<0.05)
compared to 68Ga(III); 27.53 and 0.74, respectively. In conclusion,
[68Ga]NODPAM was prepared and characterized accordingly, and the in vitro
bone binding assay and in vivo bone-to-blood ratio were assessed. The
preliminary data suggests that there is a need for a complete pre-clinical study
of [68Ga]NODPAM before translating it into clinical research. |
| first_indexed | 2025-11-15T13:46:09Z |
| format | Thesis |
| id | upm-104367 |
| institution | Universiti Putra Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-15T13:46:09Z |
| publishDate | 2020 |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | upm-1043672023-08-08T04:10:38Z http://psasir.upm.edu.my/id/eprint/104367/ Preparation and characterization of [68Ga]NODAGA-Pamidronic acid for pet bone cancer imaging Mohd Ashhar, Zarif Naim Early detection of bone metastases is essential to prevent skeletal-related events. Unlike biopsies, a non-invasive technique to diagnose bone metastases is by utilizing radiopharmaceuticals and detected using a nuclear imaging modality. Hence, this research deems to determine the role of gallium-68 radiolabeled bisphosphonates ([68Ga]NODAGA-Pamidronic acid) for PET bone cancer imaging. This study aims to ascertain the preparation, characterization, and radiolabeling of [68Ga]NODAGA-Pamidronic acid. Lastly, to determine its potential application, the in vitro bone binding assay and in vivo bone-to-blood ratio is examined. Firstly, NODAGA-Pamidronic acid (NODPAM) was prepared via the NHS ester conjugation method and characterized using tandem mass spectrometry (MS/MS). The RP-HPLC method was then developed to remove the free NODAGA using 0.1% trifluoroacetic acid and water as the mobile phase at a flow rate of 0.5 ml/ min. Based on the MS/MS analysis of NODPAM, the precursor ion and product ion observed were according to the theoretical value (theoretical [M-H]-m/z: 591.14, obtained [M-H]-m/z: 591.14, [M-H-H3PO3]-m/z: 509.17). The isotopic abundance M+1 (calculated m/z: 22.02, obtained m/z: 20.99±0.94) confirms the molecular formula C18H34N4O14P2. The HPLC method developed shows a good separation between peaks with a resolution of 1.613. The freeze-dried NODPAM produces a solid white powder. Next, the radiolabeling of [68Ga]NODPAM was optimized by looking into three parameters; pH, temperature, and amount NODPAM. Finally, the in vitro bone binding assay and in vivo bone-to-blood ratio was determined using synthetic hydroxyapatite and Sprague Dawley rats, respectively. From the results obtained, the %RCP of radiolabeled [68Ga]NODPAM was above 90% within 15 minutes at pH 4-4.5 and a temperature of above 60ºC. The in vitro hydroxyapatite (HA) bone binding assay displayed a significant difference between the [68Ga]NODPAM 82.25%±1.72 and [99mTc]MDP of 53.21%±0.28 (p<0.05). The bone-to-blood ratio of [68Ga]NODPAM 2-hour post-injection was significantly higher (P<0.05) compared to 68Ga(III); 27.53 and 0.74, respectively. In conclusion, [68Ga]NODPAM was prepared and characterized accordingly, and the in vitro bone binding assay and in vivo bone-to-blood ratio were assessed. The preliminary data suggests that there is a need for a complete pre-clinical study of [68Ga]NODPAM before translating it into clinical research. 2020-06 Thesis NonPeerReviewed text en http://psasir.upm.edu.my/id/eprint/104367/1/ZARIF%20NAIM%20MOHD%20ASHHAR%20-%20IR.pdf Mohd Ashhar, Zarif Naim (2020) Preparation and characterization of [68Ga]NODAGA-Pamidronic acid for pet bone cancer imaging. Masters thesis, Universiti Putra Malaysia. Bone metastasis Radiopharmaceuticals |
| spellingShingle | Bone metastasis Radiopharmaceuticals Mohd Ashhar, Zarif Naim Preparation and characterization of [68Ga]NODAGA-Pamidronic acid for pet bone cancer imaging |
| title | Preparation and characterization of [68Ga]NODAGA-Pamidronic acid for pet bone cancer imaging |
| title_full | Preparation and characterization of [68Ga]NODAGA-Pamidronic acid for pet bone cancer imaging |
| title_fullStr | Preparation and characterization of [68Ga]NODAGA-Pamidronic acid for pet bone cancer imaging |
| title_full_unstemmed | Preparation and characterization of [68Ga]NODAGA-Pamidronic acid for pet bone cancer imaging |
| title_short | Preparation and characterization of [68Ga]NODAGA-Pamidronic acid for pet bone cancer imaging |
| title_sort | preparation and characterization of [68ga]nodaga-pamidronic acid for pet bone cancer imaging |
| topic | Bone metastasis Radiopharmaceuticals |
| url | http://psasir.upm.edu.my/id/eprint/104367/ http://psasir.upm.edu.my/id/eprint/104367/1/ZARIF%20NAIM%20MOHD%20ASHHAR%20-%20IR.pdf |