To Evaluate Dose and Safety of NanoEcho Particle-1 Using NanoEcho Imaging Device Examinations of Rectal Lymph Nodes in Healthy Volunteers and Rectal Cancer Patients.

Inclusion Criteria:

Part A

1. Willing and able to give written informed consent for participation in the trial.
2. Healthy male participant, or female participant of non-childbearing potential aged 18 to 50 years, inclusive.
3. Body mass index (BMI) ≥ 18.5 and ≤ 30.0 kg/m2 at the time of the screening visit.
4. Medically healthy participant without abnormal clinically significant medical history, physical findings, vital signs, ECG and laboratory values at the time of the screening visit, as judged by the Investigator. (Discussion is encouraged between the Investigator and the Sponsor Medical Representative regarding the clinical relevance of any abnormal laboratory value during the pre dose period).
5. Women of non-childbearing potential are pre-menopausal females who have undergone any of the following surgical procedures; hysterectomy, bilateral salpingectomy or bilateral oophorectomy, or who are post-menopausal defined as 12 months of amenorrhea (in questionable cases a blood sample with detection of follicle stimulating hormone \[FSH\] \>25 IU/L is confirmatory).

Male participants must be willing to use condom or be vasectomised or practice sexual abstinence from heterosexual intercourse (only allowed when this is the preferred and usual lifestyle of the participant) to prevent pregnancy and drug exposure of a partner and refrain from donating sperm from the administration of IMP until 3 months after the administration of IMP. Any female partner of a non-vasectomised male participant who is of childbearing potential must use contraceptive methods with a failure rate of \< 1% to prevent pregnancy (see above) from at least 2 weeks prior to the administration of IMP to 4 weeks after the administration of IMP.

Part B

1. Willing and able to give written informed consent for participation in the trial aged 18 to 99 years, inclusive.
2. Participant with primary rectal cancer planned for surgery with suspected spread to lymph nodes. No suspicion of systemic tumour spread. MRI must have been performed within the last 3 months before administration of IMP.
3. Diagnosed with clinical stage T1-T4.
4. It should be possible to use a probe in rectum (no tumour that blocks).
5. Male participant, or female participant of non-childbearing potential ≥ 18 years of age.
6. Women of non-childbearing potential are pre-menopausal females who have undergone any of the following surgical procedures; hysterectomy, bilateral salpingectomy or bilateral oophorectomy, or who are post-menopausal defined as 12 months of amenorrhea (in questionable cases a blood sample with detection of FSH \>25 IU/L is confirmatory).

Male participants must be willing to use condom or be vasectomised or practice sexual abstinence from heterosexual intercourse (only allowed when this is the preferred and usual lifestyle of the participant) to prevent pregnancy and drug exposure of a partner and refrain from donating sperm from the administration of IMP until 3 months after the administration of IMP. Any female partner of a non-vasectomised male participant who is of childbearing potential must use contraceptive methods with a failure rate of \< 1% to prevent pregnancy (see above) from at least 2 weeks prior to the administration of IMP to 4 weeks after the administration of IMP.

Exclusion Criteria:

Part A

1. History of any clinically significant disease or disorder which, in the opinion of the Investigator, may either put the participant at risk because of participation in the trial, or influence the results or the participant's ability to participate in the trial.
2. Any clinically significant illness, medical/surgical procedure or trauma within 4 weeks of the administration of IMP.
3. Malignancy within the past 5 years, with the exception of in situ removal of basal cell carcinoma.
4. Any planned major surgery within the duration of the trial.
5. Any previous or current anorectal disorder which may increase risk or burden of trial participation.
6. Any positive result at the screening visit for serum hepatitis B surface antigen, hepatitis C antibodies and/or human immunodeficiency virus (HIV).
7. After 10 minutes supine rest at the screening visit, any vital signs values outside the following ranges: - Systolic blood pressure: \<90 or ≥140 mmHg, or - Diastolic blood pressure \<50 or ≥90 mmHg, or - Pulse \<40 or ≥90 bpm
8. Prolonged QTcF (\>450 ms), cardiac arrhythmias or any clinically significant abnormalities in the resting ECG at the screening visit, as judged by the Investigator.
9. History of severe allergy/hypersensitivity or ongoing allergy/hypersensitivity, as judged by the Investigator, or history of hypersensitivity to drugs with a similar chemical structure or class to the IMP, IMP excipients or other parenteral iron products, or excipients of the enema to be used in the trial.
10. Person with pacemaker.
11. Person with metal implants.
12. Previous history of full radiation of rectum.
13. Regular use of any prescribed or non-prescribed medications, including antacids, analgesics, herbal remedies, vitamins and minerals, within 2 weeks prior to the (first) administration of IMP, except occasional intake of paracetamol (maximum 2000 mg/day and not exceeding 3000 mg/week), as well as nasal decongestants without cortisone, antihistamine or anticholinergics for a maximum of 10 days, at the discretion of the Investigator.
14. Planned treatment or treatment with another investigational drug within 3 months prior to Day -1. Participants consented and screened but not dosed in previous phase I trials are not to be excluded.
15. Current smokers or users of nicotine products. Irregular use of nicotine (e.g., smoking, snuffing, chewing tobacco) less than three times/week is allowed before the screening visit.
16. Positive screening result for drugs of abuse or alcohol at the screening visit or on admission to the trial site prior to the (first) administration of the IMP. (Positive results that are expected given the participant's medical history and prescribed medications can be disregarded as judged by the Investigator.)
17. History of alcohol abuse or excessive intake of alcohol, as judged by the Investigator.
18. Presence or history of drug abuse, as judged by the Investigator.
19. History of, or current use of anabolic steroids, as judged by the Investigator.
20. The Investigator considers the participant unlikely to comply with trial procedures, restrictions and requirements.

Part B History of any clinically significant disease or disorder which, in the opinion of the Investigator, may either put the participant at risk because of participation in the trial, or influence the results or the participant's ability to participate in the trial.

2\. Person with any kind of stoma. 3. Person with pacemaker. 4. Person with metal implants. 5. Previous history of radiation of rectum. 6. Prescence of malignancy other than rectal cancer. 7. After 10 minutes supine rest at the screening visit, any vital signs values outside the following ranges: - Systolic blood pressure: \<90 or ≥140 mmHg, or - Diastolic blood pressure \<50 or ≥90 mmHg, or - Pulse \<40 or ≥90 bpm 8. Prolonged QTcF (\>450 ms), cardiac arrhythmias or any clinically significant abnormalities in the resting ECG at the screening visit, as judged by the Investigator.

9\. History of severe allergy/hypersensitivity or ongoing allergy/hypersensitivity, as judged by the Investigator, or history of hypersensitivity to drugs with a similar chemical structure or class to the IMP, IMP excipients or other parenteral iron products.

10\. Planned treatment or treatment with another investigational drug within 3 months prior to Day -1. Participants consented and screened but not dosed in previous phase I trials are not to be excluded.

11\. The Investigator considers the participant unlikely to comply with trial procedures, restrictions and requirements.